WEBVTT ef52afb0-7151-4b8e-a5a5-25f7cf8e64db-0 00:00:01.320 --> 00:00:02.000 Thanks, Catherine. dd49ce94-ce57-4eaf-b0e5-ebe04c0bb0f3-0 00:00:02.200 --> 00:00:05.480 So it's my pleasure to introduce our speaker today Omar Issa. cbf8d153-8d7e-4d19-a68d-fae8eaf1115d-0 00:00:05.880 --> 00:00:10.240 He is the co-founder and CEO of the start-up ResiQuant. 80972c94-f0a8-42e4-8b6e-d2bf6fd1f266-0 00:00:10.520 --> 00:00:14.268 Omar is a recent graduate from Stanford, where he earned a PhD 80972c94-f0a8-42e4-8b6e-d2bf6fd1f266-1 00:00:14.268 --> 00:00:17.541 in structural engineering working with Jack Baker, and 80972c94-f0a8-42e4-8b6e-d2bf6fd1f266-2 00:00:17.541 --> 00:00:20.755 before that a Bachelor of Science in Engineering from 80972c94-f0a8-42e4-8b6e-d2bf6fd1f266-3 00:00:20.755 --> 00:00:22.600 UCLA, which is where I met him. a82e7094-51d9-4da6-8f34-72e0b7140ea3-0 00:00:23.760 --> 00:00:27.546 Throughout his career, he's been very involved with student a82e7094-51d9-4da6-8f34-72e0b7140ea3-1 00:00:27.546 --> 00:00:29.440 chapters of both PRI and PEER. 6c0d55c6-a558-427b-8ebe-b974ed430d2f-0 00:00:29.560 --> 00:00:33.273 He's also served on the BSSC Provisions Update Committee, so 6c0d55c6-a558-427b-8ebe-b974ed430d2f-1 00:00:33.273 --> 00:00:35.160 involved in our building codes. 6ea245b2-756f-47f4-af13-884c47167a68-0 00:00:35.680 --> 00:00:38.917 He's won several awards and scholarships, including the Shaw 6ea245b2-756f-47f4-af13-884c47167a68-1 00:00:38.917 --> 00:00:41.040 Family Fellowship on Catastrophic risk. 48d2dda6-4df4-4ca6-b896-2d3e399c2de5-0 00:00:42.840 --> 00:00:47.661 And I'm really excited to hear about what he's been working on 48d2dda6-4df4-4ca6-b896-2d3e399c2de5-1 00:00:47.661 --> 00:00:50.800 at Stanford since we were last in touch. a4563352-60b3-497b-901a-355f1d779157-0 00:00:51.120 --> 00:00:52.720 So with that, I'll hand it over. 35041c0f-a467-409b-b8a3-5eb30e96d383-0 00:00:53.200 --> 00:00:56.640 Yeah, and hopefully the camera picks him up. e019006f-5c67-46d2-9f7a-b312b1979ffc-0 00:00:56.640 --> 00:00:56.960 Awesome. 56dc7cf0-dbde-41ae-9769-8c96d795e4ec-0 00:00:56.960 --> 00:00:58.080 No, thank you so much Grace. 8e291175-37c4-4f1e-a61c-9fbc7a063d31-0 00:00:58.080 --> 00:00:58.800 This is great! 8ff84586-0ff5-4a5c-8ebb-d57c0ef0b05e-0 00:00:59.160 --> 00:01:00.200 I'm very honored. 431c6107-3a18-4249-999b-1c9e09a43ab9-0 00:01:00.200 --> 00:01:03.670 I've heard that I am one of the First in this room to be giving 431c6107-3a18-4249-999b-1c9e09a43ab9-1 00:01:03.670 --> 00:01:04.240 this talk. e12d3918-f4ad-4ef6-9191-651e73f0fc64-0 00:01:04.240 --> 00:01:08.360 So there is no bar today, which is great, very relieving. bd23af3c-731e-459b-81d4-09b1ee368f81-0 00:01:09.320 --> 00:01:10.600 It's a pleasure to be here. bafdd6f0-45b8-4030-a935-103d2907a447-0 00:01:10.640 --> 00:01:14.678 I've never been on site and on the campus, so I've never had a bafdd6f0-45b8-4030-a935-103d2907a447-1 00:01:14.678 --> 00:01:15.320 reason to. 1b74cdf0-860e-4db4-a50a-98b2541ae3b4-0 00:01:15.320 --> 00:01:16.840 So I really appreciate the invitation. c0106196-d9c4-4463-b417-9b67400542fd-0 00:01:16.840 --> 00:01:18.520 It's a pleasure to meet all of you. e4ef1085-3d5f-4dc9-b73c-7e8ec97c619f-0 00:01:19.640 --> 00:01:23.273 So I thought about what, you know, maybe to talk about today, e4ef1085-3d5f-4dc9-b73c-7e8ec97c619f-1 00:01:23.273 --> 00:01:26.964 and I put together, I think, a list of things that I think are e4ef1085-3d5f-4dc9-b73c-7e8ec97c619f-2 00:01:26.964 --> 00:01:28.839 meaningful learnings for my PhD. b7649370-396a-4214-a071-761c027d5de5-0 00:01:29.160 --> 00:01:31.040 But I also want to introduce you to myself. a02a1070-4383-479a-8b92-d1653486d350-0 00:01:31.240 --> 00:01:32.360 You know, how did I get here? d5607f7f-ee83-4527-813d-83fbedd18ab2-0 00:01:32.360 --> 00:01:35.979 How do I start thinking about catastrophic risk disasters and d5607f7f-ee83-4527-813d-83fbedd18ab2-1 00:01:35.979 --> 00:01:36.680 engineering? a77ca6fa-ad3f-4cd3-9f9e-2e8f9ba19b53-0 00:01:37.360 --> 00:01:38.880 So I want to dial back the clock. 28231a58-be61-43a3-a6eb-d365c276df20-0 00:01:39.160 --> 00:01:42.502 Let's take it back maybe to the time I was born, maybe a little 28231a58-be61-43a3-a6eb-d365c276df20-1 00:01:42.502 --> 00:01:42.920 earlier. b3f6a626-efb7-4b8a-ac52-51e2ef29e464-0 00:01:43.160 --> 00:01:46.035 I was actually, I grew up in a town not too far from here in b3f6a626-efb7-4b8a-ac52-51e2ef29e464-1 00:01:46.035 --> 00:01:47.120 Danville, the East Bay. eef474e1-5759-471d-acb2-4d024f1588c3-0 00:01:47.760 --> 00:01:51.800 My dad is a structural engineer, graduated from Berkeley in 1989. 7fc64561-193b-453b-9040-4ffbb459b6e4-0 00:01:51.880 --> 00:01:55.120 His whole career was off the tailwinds of Loma Prieta. 37c4d72f-87f8-460b-a5c3-9b3b6a65b439-0 00:01:55.320 --> 00:01:58.277 He served, you know, designing, you know, schools, hospitals for 37c4d72f-87f8-460b-a5c3-9b3b6a65b439-1 00:01:58.277 --> 00:02:00.916 his career and actually was Professor Filippo's first PhD 37c4d72f-87f8-460b-a5c3-9b3b6a65b439-2 00:02:00.916 --> 00:02:01.280 student. c5814e7c-096a-45c6-8e58-baea1b9030ad-0 00:02:02.760 --> 00:02:04.863 I come from a big family, but none of my siblings did c5814e7c-096a-45c6-8e58-baea1b9030ad-1 00:02:04.863 --> 00:02:05.760 structural engineering. ee52373d-fbde-4c83-a0f7-afb8e71b65fa-0 00:02:05.760 --> 00:02:10.108 So I was really the chosen one to continue and kind of ee52373d-fbde-4c83-a0f7-afb8e71b65fa-1 00:02:10.108 --> 00:02:14.253 like, and I just followed my dad's career, discovered my own ee52373d-fbde-4c83-a0f7-afb8e71b65fa-2 00:02:14.253 --> 00:02:16.360 path in structural engineering. f9b0f570-9138-48ea-9397-b1845cb27acd-0 00:02:17.240 --> 00:02:20.703 I went to Jordan in 2009, did high school there and then kind f9b0f570-9138-48ea-9397-b1845cb27acd-1 00:02:20.703 --> 00:02:24.167 of took a lap around the world where I went to UCLA, as Grace f9b0f570-9138-48ea-9397-b1845cb27acd-2 00:02:24.167 --> 00:02:27.519 mentioned in 2015, had a great time in Southern California. f193c075-63b5-4e52-b637-f2dac574ab5c-0 00:02:27.520 --> 00:02:31.353 It's very sunny, very fun, but it's also where I discovered my f193c075-63b5-4e52-b637-f2dac574ab5c-1 00:02:31.353 --> 00:02:31.840 passion. be7086de-b5ae-49e4-addd-26620f8fd6c6-0 00:02:32.320 --> 00:02:35.409 Around 2019, Ridgecrest earthquake happened, you know, be7086de-b5ae-49e4-addd-26620f8fd6c6-1 00:02:35.409 --> 00:02:37.600 hundreds of miles east of downtown LA. a3630ccc-98d6-4c80-8b10-483cc7f2f33f-0 00:02:38.240 --> 00:02:40.424 Of course, they send the undergraduates to do the a3630ccc-98d6-4c80-8b10-483cc7f2f33f-1 00:02:40.424 --> 00:02:41.080 reconnaissance. 3e4a5ce0-359d-412e-a590-e50e1d94b100-0 00:02:41.160 --> 00:02:45.414 So I was out there in 100° heat inspecting buildings, but also 3e4a5ce0-359d-412e-a590-e50e1d94b100-1 00:02:45.414 --> 00:02:47.440 the surface fault projections 766eac29-2885-46a4-82e7-354d87c9fcff-0 00:02:47.680 --> 00:02:48.640 following the disaster. fdc2cfe4-81d6-4e36-9a4b-fbd7af161ad5-0 00:02:49.800 --> 00:02:52.652 I expected buildings in Ridgecrest and nearby Trona, but fdc2cfe4-81d6-4e36-9a4b-fbd7af161ad5-1 00:02:52.652 --> 00:02:55.755 my principal responsibility at the beginning of that time was fdc2cfe4-81d6-4e36-9a4b-fbd7af161ad5-2 00:02:55.755 --> 00:02:58.358 actually to help with the photogrammetry efforts of fdc2cfe4-81d6-4e36-9a4b-fbd7af161ad5-3 00:02:58.358 --> 00:02:59.960 preserving those fault features. dcc3bee3-396d-4df9-a2cc-9a7de5c7a5a4-0 00:02:59.960 --> 00:03:03.397 So as part of a team, it is my first time doing reconnaissance dcc3bee3-396d-4df9-a2cc-9a7de5c7a5a4-1 00:03:03.397 --> 00:03:06.835 that was extremely proud of this was joined by folks at the dcc3bee3-396d-4df9-a2cc-9a7de5c7a5a4-2 00:03:06.835 --> 00:03:10.327 Near East Center and other PhD students at dcc3bee3-396d-4df9-a2cc-9a7de5c7a5a4-3 00:03:10.327 --> 00:03:10.600 UCLA. db28f088-0222-44c2-b9ec-09fa6afd1fb8-0 00:03:11.080 --> 00:03:13.360 The default surface rupture was impressive. 76d9fc3a-85db-4d87-932a-42781d4a1204-0 00:03:13.440 --> 00:03:16.530 I was assisted with flying drones and in the end we came up 76d9fc3a-85db-4d87-932a-42781d4a1204-1 00:03:16.530 --> 00:03:19.240 with a very valuable data set that helped the community. 3d4d2b0d-07f0-40a1-944a-5998695a3eee-0 00:03:19.760 --> 00:03:23.400 But it was really looking at the buildings that inspired me. 18b62968-2b0a-4480-a994-c69bae5fd130-0 00:03:23.680 --> 00:03:26.812 There are obviously types of buildings and taxonomies that we 18b62968-2b0a-4480-a994-c69bae5fd130-1 00:03:26.812 --> 00:03:29.743 expect to suffer some type of damage in these events, but 18b62968-2b0a-4480-a994-c69bae5fd130-2 00:03:29.743 --> 00:03:31.360 there are others that we do not. dd26c9bf-c55e-47c9-90a1-1a85107c0f96-0 00:03:31.600 --> 00:03:35.889 And I think at the time when I was in Ridgecrest, hearing about dd26c9bf-c55e-47c9-90a1-1a85107c0f96-1 00:03:35.889 --> 00:03:40.111 how hospitals, in this case one of the hospitals in Ridgecrest dd26c9bf-c55e-47c9-90a1-1a85107c0f96-2 00:03:40.111 --> 00:03:44.467 had to evacuate patients who are inside due to, you know, non, I dd26c9bf-c55e-47c9-90a1-1a85107c0f96-3 00:03:44.467 --> 00:03:48.690 guess not really so severe, non structural damage kind of made dd26c9bf-c55e-47c9-90a1-1a85107c0f96-4 00:03:48.690 --> 00:03:52.912 me think about this discrepancy between our building codes and dd26c9bf-c55e-47c9-90a1-1a85107c0f96-5 00:03:52.912 --> 00:03:54.320 what society expects. 87b67825-6a63-4352-ab3d-ce028e934e81-0 00:03:54.720 --> 00:03:57.910 And this discrepancy ultimately is what inspired me to go to 87b67825-6a63-4352-ab3d-ce028e934e81-1 00:03:57.910 --> 00:04:00.630 Stanford and spend the past several years trying to 87b67825-6a63-4352-ab3d-ce028e934e81-2 00:04:00.630 --> 00:04:03.560 understand how do we design buildings not just for life 87b67825-6a63-4352-ab3d-ce028e934e81-3 00:04:03.560 --> 00:04:06.280 safety, but ultimately for recovery and resilience. 80753dd4-775e-45b0-b3f2-133487149757-0 00:04:06.640 --> 00:04:08.793 So today I'm going to share a little bit about those 80753dd4-775e-45b0-b3f2-133487149757-1 00:04:08.793 --> 00:04:09.200 learnings. a273fe99-0a1c-40d0-a9ef-1cdc5abc8e83-0 00:04:09.400 --> 00:04:12.008 I'm fresh off the press, as Grace mentioned, so they're a273fe99-0a1c-40d0-a9ef-1cdc5abc8e83-1 00:04:12.008 --> 00:04:13.080 still fresh in my head. bca5d8f0-f73e-4f16-bde5-ff78fa8bd1b5-0 00:04:13.800 --> 00:04:17.379 And the question I'll lead with is how do we design buildings bca5d8f0-f73e-4f16-bde5-ff78fa8bd1b5-1 00:04:17.379 --> 00:04:18.880 for earthquake resilience? 694d4705-c18b-45ef-bea3-eb7badc3aba5-0 00:04:19.400 --> 00:04:23.184 So let's begin by a reckoning that there is a missing link 694d4705-c18b-45ef-bea3-eb7badc3aba5-1 00:04:23.184 --> 00:04:26.840 between building codes and community resilience schools. b09a1d01-35c4-4de0-a5ec-756d9ab78fc0-0 00:04:27.640 --> 00:04:30.719 Our building codes like ASCE 716 are specified and we are b09a1d01-35c4-4de0-a5ec-756d9ab78fc0-1 00:04:30.719 --> 00:04:33.480 designing buildings in accordance with life safety. 181e1a81-ac5a-46d0-9136-51100dd78ad9-0 00:04:33.480 --> 00:04:37.090 So Omar and others can obviously leave these buildings alive, but 181e1a81-ac5a-46d0-9136-51100dd78ad9-1 00:04:37.090 --> 00:04:40.208 it is in stark contrast with community resilience goals, 181e1a81-ac5a-46d0-9136-51100dd78ad9-2 00:04:40.208 --> 00:04:43.600 which are expressed in terms of time to functionally recover. 7fb51bfb-b278-4b9a-bb0e-d32ea9d5d106-0 00:04:44.760 --> 00:04:48.314 This discrepancy has been studied, i.e., the implications of 7fb51bfb-b278-4b9a-bb0e-d32ea9d5d106-1 00:04:48.314 --> 00:04:51.440 designing for life safety in a resilience context. a9cb0a39-d726-42c3-9463-5f28f911aa15-0 00:04:51.440 --> 00:04:55.365 And studies like FEMA P-58, volume 5 found that 20 to 40% of a9cb0a39-d726-42c3-9463-5f28f911aa15-1 00:04:55.365 --> 00:04:59.613 modern code conforming buildings designed to the code today would a9cb0a39-d726-42c3-9463-5f28f911aa15-2 00:04:59.613 --> 00:05:03.345 lose occupancy and 15 to 20% would be irreparable under a a9cb0a39-d726-42c3-9463-5f28f911aa15-3 00:05:03.345 --> 00:05:04.440 major earthquake. 660836c0-0f1f-4543-b927-b131713d87bb-0 00:05:05.080 --> 00:05:08.194 So this consequence is what inspired many of us in the 660836c0-0f1f-4543-b927-b131713d87bb-1 00:05:08.194 --> 00:05:11.534 community to go above and see and explore a paradigm shift 660836c0-0f1f-4543-b927-b131713d87bb-2 00:05:11.534 --> 00:05:15.271 where maybe we don't think about life safety, but something great 660836c0-0f1f-4543-b927-b131713d87bb-3 00:05:15.271 --> 00:05:16.800 or something like recovery. b3239feb-a7a8-4dfe-a4fa-d38315f16531-0 00:05:17.200 --> 00:05:20.057 And so there has been a significant bottom-up push for b3239feb-a7a8-4dfe-a4fa-d38315f16531-1 00:05:20.057 --> 00:05:21.200 recovery based design. 999063d0-929b-45a0-a098-9d560d125631-0 00:05:21.600 --> 00:05:24.385 And we cannot talk about this push without talking about the 999063d0-929b-45a0-a098-9d560d125631-1 00:05:24.385 --> 00:05:27.307 20 years of research done by the Pacific Earthquake Engineering 999063d0-929b-45a0-a098-9d560d125631-2 00:05:27.307 --> 00:05:30.092 Research Center on the topic of performance based earthquake 999063d0-929b-45a0-a098-9d560d125631-3 00:05:30.092 --> 00:05:30.640 engineering. 044d3d97-4727-4800-b877-b1c2ed3321cc-0 00:05:31.120 --> 00:05:34.371 These approaches which are probabilistic in nature 044d3d97-4727-4800-b877-b1c2ed3321cc-1 00:05:34.371 --> 00:05:38.324 characterizing, can quantify building performance in terms of 044d3d97-4727-4800-b877-b1c2ed3321cc-2 00:05:38.324 --> 00:05:41.575 decision variables of stakeholder interest, things 044d3d97-4727-4800-b877-b1c2ed3321cc-3 00:05:41.575 --> 00:05:45.273 that have been codified in FEMA P-58, both the first and second 044d3d97-4727-4800-b877-b1c2ed3321cc-4 00:05:45.273 --> 00:05:47.760 edition and now more recently ATC 138. 5e781632-0c54-4f40-8a39-9dd2e0d371b3-0 00:05:48.080 --> 00:05:52.226 You can think of FEMA P-58 as a method that translates site 5e781632-0c54-4f40-8a39-9dd2e0d371b3-1 00:05:52.226 --> 00:05:56.788 specific hazard through building very specific buildings that are 5e781632-0c54-4f40-8a39-9dd2e0d371b3-2 00:05:56.788 --> 00:05:59.000 subject to these ground motions. b4380384-66b7-4b1e-aaf2-af6e6b4d8e31-0 00:05:59.000 --> 00:06:02.622 And then those responses are translated into damage functions b4380384-66b7-4b1e-aaf2-af6e6b4d8e31-1 00:06:02.622 --> 00:06:03.440 and then lost. [no audio] 4c98eebc-266f-467b-8a21-b0dd1ad88578-0 00:06:18.400 --> 00:06:21.634 software programs like SP3, which are used by the industry 4c98eebc-266f-467b-8a21-b0dd1ad88578-1 00:06:21.634 --> 00:06:25.197 practitioners today and Pelican that are used by researchers and 4c98eebc-266f-467b-8a21-b0dd1ad88578-2 00:06:25.197 --> 00:06:28.322 very impressive examples of recovery based design are in 4c98eebc-266f-467b-8a21-b0dd1ad88578-3 00:06:28.322 --> 00:06:31.666 practice right now, like the Oregon State Treasury building, 4c98eebc-266f-467b-8a21-b0dd1ad88578-4 00:06:31.666 --> 00:06:34.901 which I'll talk about later, which achieved very ambitious 4c98eebc-266f-467b-8a21-b0dd1ad88578-5 00:06:34.901 --> 00:06:37.916 resilience objectives through non structural component 4c98eebc-266f-467b-8a21-b0dd1ad88578-6 00:06:37.916 --> 00:06:40.931 detailing and structural structural upgrades like base 4c98eebc-266f-467b-8a21-b0dd1ad88578-7 00:06:40.931 --> 00:06:41.479 isolation. 461cbe4e-a70c-434d-bc59-5dbc70b5d254-0 00:06:41.920 --> 00:06:45.006 And then there are others that are less fancy, like Casa 461cbe4e-a70c-434d-bc59-5dbc70b5d254-1 00:06:45.006 --> 00:06:48.254 Adelante, a senior housing facility designed by David Maher 461cbe4e-a70c-434d-bc59-5dbc70b5d254-2 00:06:48.254 --> 00:06:51.340 and Justine at Berkeley that achieved at cost resilience 461cbe4e-a70c-434d-bc59-5dbc70b5d254-3 00:06:51.340 --> 00:06:54.751 through very innovative and very careful structural detailing, 461cbe4e-a70c-434d-bc59-5dbc70b5d254-4 00:06:54.751 --> 00:06:57.080 like these dampers in the Matt Foundation. a3409146-9d5e-44cc-b861-794549ce94b1-0 00:06:57.960 --> 00:07:00.600 This push that we're seeing by the private sector. db304816-55d9-4800-90c9-f9b48f32ec0c-0 00:07:00.600 --> 00:07:03.944 And you know, I think more bottoms up by engineers, more db304816-55d9-4800-90c9-f9b48f32ec0c-1 00:07:03.944 --> 00:07:07.581 grass roots is complemented by an equal and opposite top down db304816-55d9-4800-90c9-f9b48f32ec0c-2 00:07:07.581 --> 00:07:08.520 push from above. fb61b862-eaa1-49b4-a34d-71683b2d8553-0 00:07:08.600 --> 00:07:12.058 Starting with this white paper from the Earthquake Engineering fb61b862-eaa1-49b4-a34d-71683b2d8553-1 00:07:12.058 --> 00:07:15.077 Research Institute in 2019, specifying what functional fb61b862-eaa1-49b4-a34d-71683b2d8553-2 00:07:15.077 --> 00:07:18.041 recovery as a conceptual framework and policy options fb61b862-eaa1-49b4-a34d-71683b2d8553-3 00:07:18.041 --> 00:07:18.920 might look like. cfd20e2b-912f-4672-a50a-8674ecd68177-0 00:07:18.960 --> 00:07:23.018 And we can think of functional recovery as this limit state cfd20e2b-912f-4672-a50a-8674ecd68177-1 00:07:23.018 --> 00:07:26.806 above life safety where we are not looking for collapse cfd20e2b-912f-4672-a50a-8674ecd68177-2 00:07:26.806 --> 00:07:30.526 prevention, but rather the minimum set of repairs that cfd20e2b-912f-4672-a50a-8674ecd68177-3 00:07:30.526 --> 00:07:34.314 restore a building's, I guess like minimum cfd20e2b-912f-4672-a50a-8674ecd68177-4 00:07:34.314 --> 00:07:35.600 intended functions. 5df0a130-1719-427f-940d-4325ee9d8b69-0 00:07:35.600 --> 00:07:38.578 So things like chips and wallboard, things like very 5df0a130-1719-427f-940d-4325ee9d8b69-1 00:07:38.578 --> 00:07:42.120 basic cosmetic damages are not considered in this limit state. e7a6e017-6406-489d-be22-fafe241595ac-0 00:07:42.160 --> 00:07:44.425 It's basically how do we get us back in the building and doing e7a6e017-6406-489d-be22-fafe241595ac-1 00:07:44.425 --> 00:07:45.360 what we were doing before. 2085d58c-cabf-4517-b0f0-baedfac2d967-0 00:07:45.800 --> 00:07:49.771 Since then, 2021, the NIST FEMA report to Congress released, and 2085d58c-cabf-4517-b0f0-baedfac2d967-1 00:07:49.771 --> 00:07:53.681 then more recently in 2022, the Building Seismic Safety Council 2085d58c-cabf-4517-b0f0-baedfac2d967-2 00:07:53.681 --> 00:07:57.224 forming the 2026 PUC committee to explore what functional 2085d58c-cabf-4517-b0f0-baedfac2d967-3 00:07:57.224 --> 00:08:01.134 recovery might look like in the next generation of the building 2085d58c-cabf-4517-b0f0-baedfac2d967-4 00:08:01.134 --> 00:08:01.440 code. 92bf7c6b-e41d-4100-a918-e2cb3f1044bf-0 00:08:01.920 --> 00:08:04.908 Despite all this progress that I'm very optimistic about the 92bf7c6b-e41d-4100-a918-e2cb3f1044bf-1 00:08:04.908 --> 00:08:07.946 strategies for recovery based design like how do we get 92bf7c6b-e41d-4100-a918-e2cb3f1044bf-2 00:08:07.946 --> 00:08:10.200 to resilience are still not well established. 7ea08da2-1105-4116-94f5-5860f089681e-0 00:08:10.560 --> 00:08:13.179 And the way we can think about this is first looking at life 7ea08da2-1105-4116-94f5-5860f089681e-1 00:08:13.179 --> 00:08:13.480 safety. 3c655e87-6e32-4f40-80ef-320296b056e1-0 00:08:13.800 --> 00:08:17.140 In the world of life safety, we have a good handle on effective 3c655e87-6e32-4f40-80ef-320296b056e1-1 00:08:17.140 --> 00:08:18.080 design strategies. cd9b113c-b5af-40cc-bc68-c0b6ed01dd66-0 00:08:18.360 --> 00:08:20.120 These strategies are generally additive. 5d06ed03-3ab6-41ba-afbd-d5e51f08aa5b-0 00:08:20.120 --> 00:08:23.736 We know that we can confidently dampen here, stiffen the 5d06ed03-3ab6-41ba-afbd-d5e51f08aa5b-1 00:08:23.736 --> 00:08:27.288 structure there and generally speaking we are achieving 5d06ed03-3ab6-41ba-afbd-d5e51f08aa5b-2 00:08:27.288 --> 00:08:31.158 additive benefits in terms of collapse safety or life safety 5d06ed03-3ab6-41ba-afbd-d5e51f08aa5b-3 00:08:31.158 --> 00:08:31.920 performance. 0e527a2d-d587-4b50-9d7f-d77193d72f7e-0 00:08:32.320 --> 00:08:36.352 And then finally, if we look at performance objectives, they're 0e527a2d-d587-4b50-9d7f-d77193d72f7e-1 00:08:36.352 --> 00:08:36.920 in place. aa05cb6f-93ab-4f22-ac73-75e3a53acd84-0 00:08:36.920 --> 00:08:38.360 We know what we're, we know what we're looking for. a3c4c519-4323-4d72-ac08-b4a5ad5c34bc-0 00:08:38.360 --> 00:08:41.480 We know what we're optimizing for and the work and and the a3c4c519-4323-4d72-ac08-b4a5ad5c34bc-1 00:08:41.480 --> 00:08:44.760 strategy or the design space is generally very, very limited. 6fa8c4b4-53d4-4e6f-b231-b24c284d4570-0 00:08:45.120 --> 00:08:46.908 When you look at functional recovery, things are very 6fa8c4b4-53d4-4e6f-b231-b24c284d4570-1 00:08:46.908 --> 00:08:47.240 different. d8f5e1b3-4fb1-4d8b-b885-2b3cbeaeb265-0 00:08:47.760 --> 00:08:50.800 There is a lack of intuition on effective design strategies. 9493c434-1af6-482f-b551-0cdb603306a1-0 00:08:51.120 --> 00:08:53.600 These strategies can also lead to counteractive effects. 5ebcc1bd-610b-4a9b-b112-6ed54788630b-0 00:08:53.920 --> 00:08:56.770 When we stiffen a structure, a lot of the times what we're 5ebcc1bd-610b-4a9b-b112-6ed54788630b-1 00:08:56.770 --> 00:08:59.814 doing is we are increasing or amplifying accelerations in part 5ebcc1bd-610b-4a9b-b112-6ed54788630b-2 00:08:59.814 --> 00:09:02.520 of the buildings that may attenuate the benefits of non 5ebcc1bd-610b-4a9b-b112-6ed54788630b-3 00:09:02.520 --> 00:09:03.680 structural improvements. b633c1b5-cd79-48af-8a15-69bc3afc8a54-0 00:09:04.000 --> 00:09:06.323 And then finally, performance objectives are not well b633c1b5-cd79-48af-8a15-69bc3afc8a54-1 00:09:06.323 --> 00:09:06.840 established. f0afd487-ea23-41a5-8057-0df5566b5a95-0 00:09:06.840 --> 00:09:07.880 It's pretty complicated. 2f74df52-62ce-4868-ac43-309982e3545a-0 00:09:07.880 --> 00:09:11.003 We don't necessarily know as a society what we are looking for 2f74df52-62ce-4868-ac43-309982e3545a-1 00:09:11.003 --> 00:09:14.077 in the context of functional recovery and the design space is 2f74df52-62ce-4868-ac43-309982e3545a-2 00:09:14.077 --> 00:09:14.920 very, very large. c7cb61c9-1a61-4bdb-9cf3-0e4f7546b583-0 00:09:15.200 --> 00:09:18.623 Not only do we have structural improvements, we can improve non c7cb61c9-1a61-4bdb-9cf3-0e4f7546b583-1 00:09:18.623 --> 00:09:19.800 structural components. 71e0b801-93f1-4050-a47d-0140af774f52-0 00:09:19.800 --> 00:09:22.536 We can look at utility backup and redundancy actions and 71e0b801-93f1-4050-a47d-0140af774f52-1 00:09:22.536 --> 00:09:23.400 recovery planning. dc2cb61b-1129-407c-be42-323d63d8eb98-0 00:09:23.640 --> 00:09:26.966 And so this becomes a very high dimensional space and it's dc2cb61b-1129-407c-be42-323d63d8eb98-1 00:09:26.966 --> 00:09:30.405 highly nonlinear, meaning that these individual improvements dc2cb61b-1129-407c-be42-323d63d8eb98-2 00:09:30.405 --> 00:09:34.014 are not necessarily going to add on one another in an intuitive dc2cb61b-1129-407c-be42-323d63d8eb98-3 00:09:34.014 --> 00:09:34.239 way. 81f39dbe-9f24-4e58-abdd-2b1be7d4947f-0 00:09:34.520 --> 00:09:37.459 And so it can become very difficult to scan and search for 81f39dbe-9f24-4e58-abdd-2b1be7d4947f-1 00:09:37.459 --> 00:09:40.000 resource efficient design strategies for recovery. 28afe1e8-fcfd-4f87-be97-499d2e6de595-0 00:09:40.560 --> 00:09:43.496 And So what I propose in my PhD is a multi faceted approach 28afe1e8-fcfd-4f87-be97-499d2e6de595-1 00:09:43.496 --> 00:09:45.160 focusing on two important things. 3778535b-3333-49fd-b03a-78bb776320cb-0 00:09:45.160 --> 00:09:48.114 The first is how do we rigorously select these 3778535b-3333-49fd-b03a-78bb776320cb-1 00:09:48.114 --> 00:09:50.440 performance objectives for recovery? ed5c4d0f-f4ba-44f1-89d8-c40ff5c93d43-0 00:09:50.880 --> 00:09:54.679 And then once we know what we want, how do we rapidly extract ed5c4d0f-f4ba-44f1-89d8-c40ff5c93d43-1 00:09:54.679 --> 00:09:57.560 efficient designs to achieve those objectives? 83b21f56-b6e3-4cb5-aa4f-d4b747e310d8-0 00:09:58.040 --> 00:10:01.095 And if we can do those two things and we can repeat them 83b21f56-b6e3-4cb5-aa4f-d4b747e310d8-1 00:10:01.095 --> 00:10:03.936 hundreds, thousands of times across different sites, 83b21f56-b6e3-4cb5-aa4f-d4b747e310d8-2 00:10:03.936 --> 00:10:06.670 different building configurations, only then in my 83b21f56-b6e3-4cb5-aa4f-d4b747e310d8-3 00:10:06.670 --> 00:10:09.887 belief, I guess here will we be able to accelerate recovery 83b21f56-b6e3-4cb5-aa4f-d4b747e310d8-4 00:10:09.887 --> 00:10:11.119 based design intuition. b16c36c7-d46d-4971-b05b-2a704e8df489-0 00:10:11.120 --> 00:10:12.000 We need more examples. 1deab694-0c35-4911-a0a5-d3d1becc1911-0 00:10:12.000 --> 00:10:13.600 We need to be able to search the design space. 4c4fe84b-71e1-4a69-9f1d-6cf14c2d648c-0 00:10:14.040 --> 00:10:16.360 So today I'm going to talk about a few research objectives. 32799a27-214c-4bc3-b821-3da14c4add56-0 00:10:16.360 --> 00:10:19.485 I won't go through everything here, but I think there are a 32799a27-214c-4bc3-b821-3da14c4add56-1 00:10:19.485 --> 00:10:21.360 couple that are important to share. ef2f9ef0-7517-4c59-ba30-5878526d0c99-0 00:10:21.600 --> 00:10:24.646 The first objective is the recovery based performance, ef2f9ef0-7517-4c59-ba30-5878526d0c99-1 00:10:24.646 --> 00:10:26.640 objective selection and evaluation. a4b961ba-db1e-4121-8c4b-c27794ca225d-0 00:10:26.640 --> 00:10:29.180 I'm assuming many of you in the audience and online have will a4b961ba-db1e-4121-8c4b-c27794ca225d-1 00:10:29.180 --> 00:10:31.640 find some of this familiar in the world of collapse safety. 6eeba557-f730-4941-a667-e35b95bbb93f-0 00:10:31.640 --> 00:10:33.960 And I think it's it's a relevant topic for today. 5fac5148-4c26-4bf5-bf51-df28cb7278da-0 00:10:33.960 --> 00:10:37.431 And then the second is that other piece I was mentioning of 5fac5148-4c26-4bf5-bf51-df28cb7278da-1 00:10:37.431 --> 00:10:39.920 how do we isolate those design strategies. aa576ba7-0bd5-4af1-a04c-286aa05ba3cf-0 00:10:40.080 --> 00:10:43.577 So I'm going to talk about those two in my PHDI did a little bit aa576ba7-0bd5-4af1-a04c-286aa05ba3cf-1 00:10:43.577 --> 00:10:47.074 more work on the topic of how do we optimize design for lifetime aa576ba7-0bd5-4af1-a04c-286aa05ba3cf-2 00:10:47.074 --> 00:10:50.303 performance considering all the seismic intensities and all aa576ba7-0bd5-4af1-a04c-286aa05ba3cf-3 00:10:50.303 --> 00:10:52.240 their relative rates of occurrence. 6021df6c-2e30-403f-b36e-023143cd8bd2-0 00:10:52.240 --> 00:10:55.232 I won't talk about that today since just to kind of leave time 6021df6c-2e30-403f-b36e-023143cd8bd2-1 00:10:55.232 --> 00:10:57.845 for discussion and I'll kick things off with the first 6021df6c-2e30-403f-b36e-023143cd8bd2-2 00:10:57.845 --> 00:10:58.320 objective. eb049556-6e83-40d9-ac86-d9b1097956e4-0 00:10:59.360 --> 00:11:05.032 This first study I did alongside Doctor Dustin Cook with NIST and eb049556-6e83-40d9-ac86-d9b1097956e4-1 00:11:05.032 --> 00:11:05.720 then Dr. 4b82254b-5f2b-4f5d-b200-b7321dca4139-0 00:11:05.720 --> 00:11:07.280 Nicholas Luto from the USGS. 85643da2-2e90-4677-8376-5db83848fb10-0 00:11:08.120 --> 00:11:12.191 So the motivation here and just context setting is that recovery 85643da2-2e90-4677-8376-5db83848fb10-1 00:11:12.191 --> 00:11:16.200 based performance objectives are an area of active exploration. ff444d0a-d200-47e3-ac4a-2bae4c7264c5-0 00:11:16.200 --> 00:11:17.360 We're still figuring things out. 37706edf-3982-4270-a4cc-538949904046-0 00:11:17.720 --> 00:11:20.872 And as I mentioned, the VSSC formed the provision update 37706edf-3982-4270-a4cc-538949904046-1 00:11:20.872 --> 00:11:24.357 committee to explore this and they formed what they're calling 37706edf-3982-4270-a4cc-538949904046-2 00:11:24.357 --> 00:11:27.786 the FRTC, lots of acronyms here, the functional recovery Task 37706edf-3982-4270-a4cc-538949904046-3 00:11:27.786 --> 00:11:31.160 committee that is split into, of course, more subcommittees. 59a1aa2b-5119-4595-86bc-88abd94c4812-0 00:11:31.160 --> 00:11:32.600 So there's five subcommittees here. 7611f8a4-e5fc-4e80-88d4-c3e4ed8a5167-0 00:11:32.880 --> 00:11:35.866 The first is looking at key terms, performance metrics, 7611f8a4-e5fc-4e80-88d4-c3e4ed8a5167-1 00:11:35.866 --> 00:11:38.960 target times, prescriptive provisions, and hazard levels. b5c8689d-2ecf-4185-890b-4eed0ed4b0e4-0 00:11:39.520 --> 00:11:42.313 And in my conversations with folks here, which is a very b5c8689d-2ecf-4185-890b-4eed0ed4b0e4-1 00:11:42.313 --> 00:11:45.351 talented group of of individuals who are diving into this and b5c8689d-2ecf-4185-890b-4eed0ed4b0e4-2 00:11:45.351 --> 00:11:48.144 trying to see how we can fit functional recovery in many b5c8689d-2ecf-4185-890b-4eed0ed4b0e4-3 00:11:48.144 --> 00:11:51.133 times this idea of what is a good performance objective came b5c8689d-2ecf-4185-890b-4eed0ed4b0e4-4 00:11:51.133 --> 00:11:51.280 up. 56fd6774-5c66-41c0-83ea-1ff6132a8b58-0 00:11:51.760 --> 00:11:55.243 And so in spirit of trying to provide a more rigorous basis to 56fd6774-5c66-41c0-83ea-1ff6132a8b58-1 00:11:55.243 --> 00:11:58.727 select and evaluate performance objectives outside even the US 56fd6774-5c66-41c0-83ea-1ff6132a8b58-2 00:11:58.727 --> 00:12:01.768 context or outside of the provisions context, I define 56fd6774-5c66-41c0-83ea-1ff6132a8b58-3 00:12:01.768 --> 00:12:05.252 performance objectives in this study in terms of two important 56fd6774-5c66-41c0-83ea-1ff6132a8b58-4 00:12:05.252 --> 00:12:07.520 pieces, a goal and a checking procedure. 788f26bc-fe2b-4f05-8e45-bcb4bfc3ddb7-0 00:12:08.040 --> 00:12:11.640 The goal is setting the lifetime risk target. d9eb12ad-45f0-4dc2-9b91-bd52a60e7075-0 00:12:11.920 --> 00:12:15.080 What do we want to achieve over the lifetime of the building? d608ea29-8915-4cb2-b0ff-8675b3f1b33f-0 00:12:15.560 --> 00:12:18.698 And we are doing so by expressing this lifetime d608ea29-8915-4cb2-b0ff-8675b3f1b33f-1 00:12:18.698 --> 00:12:23.014 performance metric, For example, the probability of failure in 50 d608ea29-8915-4cb2-b0ff-8675b3f1b33f-2 00:12:23.014 --> 00:12:26.807 years to be less than some threshold Z, where failure can d608ea29-8915-4cb2-b0ff-8675b3f1b33f-3 00:12:26.807 --> 00:12:30.992 be a limit state, where maybe we define a target time exceeding d608ea29-8915-4cb2-b0ff-8675b3f1b33f-4 00:12:30.992 --> 00:12:34.720 some threshold, for example, exceeding 30 days, 60 days. 41b48bd3-a92c-4c9a-9a53-8dc3a0a40c03-0 00:12:34.720 --> 00:12:37.480 That's something that society or different stakeholders will set. 6cad9b1a-b421-4d14-84ad-efd8d3dfe471-0 00:12:37.680 --> 00:12:39.800 But let's keep it simple and define it as failure. a75a5045-8f37-403d-89a3-d15b92a3b0c6-0 00:12:40.440 --> 00:12:44.100 If we do so, then what we'll end up with here is probably a site a75a5045-8f37-403d-89a3-d15b92a3b0c6-1 00:12:44.100 --> 00:12:47.310 specific hazard curve for a building that quantifies the a75a5045-8f37-403d-89a3-d15b92a3b0c6-2 00:12:47.310 --> 00:12:50.801 annual rate of exceeding some intensity on the Y axis with an a75a5045-8f37-403d-89a3-d15b92a3b0c6-3 00:12:50.801 --> 00:12:53.786 intensity on the X axis superimposed with a building a75a5045-8f37-403d-89a3-d15b92a3b0c6-4 00:12:53.786 --> 00:12:57.052 fragility that represents the probability of that failure a75a5045-8f37-403d-89a3-d15b92a3b0c6-5 00:12:57.052 --> 00:12:59.080 state conditioned on the intensity. e8e4c163-5b3c-4345-9d5d-51d34363e473-0 00:12:59.480 --> 00:13:03.155 And if we integrate these, the fragility with the slope of the e8e4c163-5b3c-4345-9d5d-51d34363e473-1 00:13:03.155 --> 00:13:06.772 hazard curve, we can come up with a rate of failure and using e8e4c163-5b3c-4345-9d5d-51d34363e473-2 00:13:06.772 --> 00:13:09.806 that rate of failure and assuming a Poisson process e8e4c163-5b3c-4345-9d5d-51d34363e473-3 00:13:09.806 --> 00:13:12.840 calculating the probability of failure in 50 years. a2028955-1b9c-4f3e-bed1-a898cbc25b3b-0 00:13:13.240 --> 00:13:16.659 This is one way of expressing our goal in design, though we a2028955-1b9c-4f3e-bed1-a898cbc25b3b-1 00:13:16.659 --> 00:13:19.680 will never really do this for every single building. 106c70a2-401a-4b64-bcc2-6b8a31602172-0 00:13:19.680 --> 00:13:21.160 We will never look at lifetime risk. d7bdb911-9236-43a7-8f62-47b463e47bcc-0 00:13:21.400 --> 00:13:25.217 So in typically what we do is we perform a check, the check d7bdb911-9236-43a7-8f62-47b463e47bcc-1 00:13:25.217 --> 00:13:28.080 gauges whether or not the goal has been met. c75f8157-e26d-4828-98fe-f3acf4a18685-0 00:13:28.080 --> 00:13:29.760 And I'll show some examples in a bit. 46aef0b3-d5e9-4a11-a8f5-b2744e1b7c1d-0 00:13:30.240 --> 00:13:33.426 The way that we specify the check is gauging the failure 46aef0b3-d5e9-4a11-a8f5-b2744e1b7c1d-1 00:13:33.426 --> 00:13:36.779 probability or checking the failure probability at a single 46aef0b3-d5e9-4a11-a8f5-b2744e1b7c1d-2 00:13:36.779 --> 00:13:39.853 intensity and ensuring that that intense, that failure 46aef0b3-d5e9-4a11-a8f5-b2744e1b7c1d-3 00:13:39.853 --> 00:13:43.040 probability is less than this user selected threshold Y. 901b172e-e371-4bdc-a79f-52778182190d-0 00:13:43.640 --> 00:13:46.367 Taking a look at that same fragility, what we are 901b172e-e371-4bdc-a79f-52778182190d-1 00:13:46.367 --> 00:13:49.859 effectively doing is trying to make sure that one point on that 901b172e-e371-4bdc-a79f-52778182190d-2 00:13:49.859 --> 00:13:53.351 fragility is less than Y, IE we are guaranteeing performance on 901b172e-e371-4bdc-a79f-52778182190d-3 00:13:53.351 --> 00:13:56.897 one point of the curve and we're using that as a proxy to say we 901b172e-e371-4bdc-a79f-52778182190d-4 00:13:56.897 --> 00:13:57.880 have met the goal. e6951a91-2296-4558-a6ec-15ac82bdb6f1-0 00:13:58.360 --> 00:14:00.659 The problem with this and the challenge is that we're only e6951a91-2296-4558-a6ec-15ac82bdb6f1-1 00:14:00.659 --> 00:14:01.400 checking one point. de8b8335-deb9-4cd1-9283-ed226691ef53-0 00:14:01.680 --> 00:14:04.964 The fragility can look different in different parts of the curve, de8b8335-deb9-4cd1-9283-ed226691ef53-1 00:14:04.964 --> 00:14:07.951 and that is where this research comes in to say what is the de8b8335-deb9-4cd1-9283-ed226691ef53-2 00:14:07.951 --> 00:14:08.200 what? d6983e26-8c77-4e1b-8d2d-0a5b499fa40a-0 00:14:08.200 --> 00:14:10.974 What are the implications of that selection of why on our d6983e26-8c77-4e1b-8d2d-0a5b499fa40a-1 00:14:10.974 --> 00:14:12.840 confidence that the goal has been met. 55009351-fa02-448f-a7e4-5e667c478662-0 00:14:13.480 --> 00:14:17.674 So taking a dive deeper, let's look at how this looks like in 55009351-fa02-448f-a7e4-5e667c478662-1 00:14:17.674 --> 00:14:18.960 different contexts. eecc72b1-fa91-4e99-a75f-6da03d4623e1-0 00:14:18.960 --> 00:14:21.444 I'm going to start with what we're familiar with, which is eecc72b1-fa91-4e99-a75f-6da03d4623e1-1 00:14:21.444 --> 00:14:22.960 collapse, Collapse and life safety. d01e8b67-63e3-4c01-aeec-04ff691dd6dc-0 00:14:23.360 --> 00:14:26.120 So in the world of life safety, the limit state is binary. 48404b0c-bd73-46b9-8e3f-c86279966923-0 00:14:26.120 --> 00:14:27.240 You collapse or you don't. 3f9c4fc4-0993-45b1-bf18-16fd4af75d08-0 00:14:27.720 --> 00:14:30.618 The goal that we use in terms, you know in the building code 3f9c4fc4-0993-45b1-bf18-16fd4af75d08-1 00:14:30.618 --> 00:14:33.184 today is we're specifying a failure as collapse and a 3f9c4fc4-0993-45b1-bf18-16fd4af75d08-2 00:14:33.184 --> 00:14:35.560 probability of collapse in 50 years less than 1%. 51b38035-8101-4694-a82f-c711d693bee7-0 00:14:36.040 --> 00:14:38.389 But we never really actually check this for every single 51b38035-8101-4694-a82f-c711d693bee7-1 00:14:38.389 --> 00:14:40.080 building we can get into technicalities. a6989f29-bbb7-417a-8e2d-cbf7f57638b7-0 00:14:40.400 --> 00:14:43.642 I'd say the better way to frame it is we are checking quoting a6989f29-bbb7-417a-8e2d-cbf7f57638b7-1 00:14:43.642 --> 00:14:46.517 quote that collapse at the M at the maximum considered a6989f29-bbb7-417a-8e2d-cbf7f57638b7-2 00:14:46.517 --> 00:14:49.550 earthquake ground motion intensity at a site is less than a6989f29-bbb7-417a-8e2d-cbf7f57638b7-3 00:14:49.550 --> 00:14:49.760 10%. 4ab7c9da-3e3d-4433-8166-98d071d2a1b4-0 00:14:50.080 --> 00:14:52.110 Of course, what we're really doing is we're not even really 4ab7c9da-3e3d-4433-8166-98d071d2a1b4-1 00:14:52.110 --> 00:14:53.160 checking this either in design. a2247dcb-d5eb-4677-bb8a-b9de9d1cd03c-0 00:14:53.160 --> 00:14:55.801 We're actually following the equivalent lateral force a2247dcb-d5eb-4677-bb8a-b9de9d1cd03c-1 00:14:55.801 --> 00:14:58.835 procedure in the building code that is a proxy for getting to a2247dcb-d5eb-4677-bb8a-b9de9d1cd03c-2 00:14:58.835 --> 00:14:59.080 this. c2f9d244-0350-4f0f-99bc-131e9e714d35-0 00:14:59.400 --> 00:15:02.202 But my point here is that we're only checking one point on that c2f9d244-0350-4f0f-99bc-131e9e714d35-1 00:15:02.202 --> 00:15:02.640 fragility. 3e2c4c46-9925-483c-91f1-ff533dfc3d1c-0 00:15:03.440 --> 00:15:06.795 Now, in the world of functional recovery, the limit stays a bit 3e2c4c46-9925-483c-91f1-ff533dfc3d1c-1 00:15:06.795 --> 00:15:07.320 different. eac76163-484b-4a1c-8d5c-da0517cde0ed-0 00:15:07.600 --> 00:15:11.365 In this case, we are concerned about exceeding unacceptable eac76163-484b-4a1c-8d5c-da0517cde0ed-1 00:15:11.365 --> 00:15:14.440 downtime, unacceptable functional recovery time. 0edb2bb7-7c2c-4d33-a156-e291d98029ac-0 00:15:14.720 --> 00:15:16.360 How does that look like in terms of a goal? 4a93699b-8870-49ba-8b6b-5123cd52ac9f-0 00:15:16.800 --> 00:15:17.880 Well, it's not very clear. 2fc7558c-18ad-4f29-a90d-7d2b533ebaac-0 00:15:18.200 --> 00:15:19.720 And how does that look like in terms of a check? 9da69030-0b42-4472-897c-e97c60177d1f-0 00:15:20.000 --> 00:15:20.960 Well, that's also not clear. 8e27a4ca-d70f-49b1-857a-2303a11a7a9d-0 00:15:21.080 --> 00:15:24.164 So as part of this research, we really tried to dive in and try 8e27a4ca-d70f-49b1-857a-2303a11a7a9d-1 00:15:24.164 --> 00:15:26.862 to see if we can help provide some clarity on these two 8e27a4ca-d70f-49b1-857a-2303a11a7a9d-2 00:15:26.862 --> 00:15:27.200 pieces. 2d5eb75d-4ffc-4678-af23-93c5cffa9153-0 00:15:27.560 --> 00:15:31.446 I'm going to start with the goal and in shedding light on it, I 2d5eb75d-4ffc-4678-af23-93c5cffa9153-1 00:15:31.446 --> 00:15:35.029 want to start by showing you some results where we analyze 2d5eb75d-4ffc-4678-af23-93c5cffa9153-2 00:15:35.029 --> 00:15:38.248 trends across different performance goal metrics, IE 2d5eb75d-4ffc-4678-af23-93c5cffa9153-3 00:15:38.248 --> 00:15:40.920 different ways of expressing lifetime risk. 9e3e439c-cbdd-4a90-8280-2973e4ab4077-0 00:15:41.840 --> 00:15:45.766 So to start this study, we begin by looking at trends across 9e3e439c-cbdd-4a90-8280-2973e4ab4077-1 00:15:45.766 --> 00:15:47.440 performance, full metrics. e27baa81-256b-4ee8-8bdd-97c6b736fcf2-0 00:15:47.440 --> 00:15:50.520 There's different ways of characterizing lifetime risks. 807cf56e-9966-4394-a9a1-0deaec9906e3-0 00:15:50.960 --> 00:15:54.049 And So what we did is we analyzed a large set of code 807cf56e-9966-4394-a9a1-0deaec9906e3-1 00:15:54.049 --> 00:15:57.425 conforming archetype buildings that that we can easily put 807cf56e-9966-4394-a9a1-0deaec9906e3-2 00:15:57.425 --> 00:15:59.599 together using some numerical models. 994e8725-cedb-491d-a193-5cd13bae44f0-0 00:16:00.040 --> 00:16:03.652 So what we did is we started with a simple three story 994e8725-cedb-491d-a193-5cd13bae44f0-1 00:16:03.652 --> 00:16:07.200 building design designed in accordance with ASCE 716. 2aff3d29-9fb5-486e-84a3-0074b3492a12-0 00:16:07.200 --> 00:16:10.424 Henry Burton and his team at UCLA have pulled together a very 2aff3d29-9fb5-486e-84a3-0074b3492a12-1 00:16:10.424 --> 00:16:12.920 helpful Python module for this called Auto SDA. b0afb73e-60de-4418-8978-ba5cb59e4f94-0 00:16:13.360 --> 00:16:16.769 We designed it in Oakland with a commercial occupancy type using b0afb73e-60de-4418-8978-ba5cb59e4f94-1 00:16:16.769 --> 00:16:18.920 a special moment resisting frame system. fa31d39b-e473-4c09-b8ab-6596142b9f85-0 00:16:19.360 --> 00:16:20.600 And we designed it in two ways. c661b1d6-1b2f-4f65-b18f-9493e1281ce2-0 00:16:20.920 --> 00:16:24.520 First using a baseline case with 2.5% drift. 76f23cca-5a85-444a-91d3-a766effabdc5-0 00:16:24.560 --> 00:16:26.940 Then we cut that drift limit in half to structurally stiff in 76f23cca-5a85-444a-91d3-a766effabdc5-1 00:16:26.940 --> 00:16:27.440 the building. 332dd6eb-d73d-4677-908d-a126213a7e32-0 00:16:28.040 --> 00:16:30.656 And then what we did is we randomly hardened a bunch of non 332dd6eb-d73d-4677-908d-a126213a7e32-1 00:16:30.656 --> 00:16:32.400 structural components in the buildings. 8195fe60-3f87-409c-af64-80630255d791-0 00:16:32.400 --> 00:16:35.545 That is, we went in the model and for say a list of 36 8195fe60-3f87-409c-af64-80630255d791-1 00:16:35.545 --> 00:16:39.205 components, maybe it's the, you know, the HVAC units, it's the, 8195fe60-3f87-409c-af64-80630255d791-2 00:16:39.205 --> 00:16:42.694 you know, the facade elements, it's the all of the different 8195fe60-3f87-409c-af64-80630255d791-3 00:16:42.694 --> 00:16:45.440 components that make up a, a performance model. 3174efff-679e-432b-a423-9d141b232b0d-0 00:16:45.760 --> 00:16:48.377 In the FEMA P 58 assessment that I mentioned to you at the 3174efff-679e-432b-a423-9d141b232b0d-1 00:16:48.377 --> 00:16:51.128 beginning, we just went in and tried to create a large set of 3174efff-679e-432b-a423-9d141b232b0d-2 00:16:51.128 --> 00:16:53.879 designs by randomly picking and choosing different components 3174efff-679e-432b-a423-9d141b232b0d-3 00:16:53.879 --> 00:16:55.920 and strengthening them or making them weaker. 95fdcbd3-f31f-4b4f-81bb-939c957006b1-0 00:16:56.280 --> 00:16:58.920 And that gave us a very large data set of building signs. c7dd029f-e9f6-4390-ba9e-054937008c2c-0 00:16:59.240 --> 00:17:02.619 Then what we did is we ran a time base, which is one way of c7dd029f-e9f6-4390-ba9e-054937008c2c-1 00:17:02.619 --> 00:17:05.999 saying an assessment using the performance based earthquake c7dd029f-e9f6-4390-ba9e-054937008c2c-2 00:17:05.999 --> 00:17:09.435 engineering methodology that considers lifetime risk, IE not c7dd029f-e9f6-4390-ba9e-054937008c2c-3 00:17:09.435 --> 00:17:13.096 just risk at a single intensity, but across all intensities that c7dd029f-e9f6-4390-ba9e-054937008c2c-4 00:17:13.096 --> 00:17:15.800 could happen over the lifetime of the building. b6d2b061-afee-4e79-8cfd-5d4d9c7bd47c-0 00:17:15.920 --> 00:17:18.740 And we're always assuming in this case a lifetime or a time b6d2b061-afee-4e79-8cfd-5d4d9c7bd47c-1 00:17:18.740 --> 00:17:19.680 horizon of 50 years. a085125b-11b3-49ac-b8c8-1a8cff9a05fc-0 00:17:19.960 --> 00:17:23.931 And what we did after generating 10,000 of these designs under a085125b-11b3-49ac-b8c8-1a8cff9a05fc-1 00:17:23.931 --> 00:17:27.650 these circumstances is we recorded the lifetime risk using a085125b-11b3-49ac-b8c8-1a8cff9a05fc-2 00:17:27.650 --> 00:17:31.370 a few different performance flow metrics to show how maybe a085125b-11b3-49ac-b8c8-1a8cff9a05fc-3 00:17:31.370 --> 00:17:35.215 success in one metric may not necessarily lead to success in a085125b-11b3-49ac-b8c8-1a8cff9a05fc-4 00:17:35.215 --> 00:17:35.720 another. baa635d5-bfd5-4dcc-9c9e-52bee7be41ac-0 00:17:36.560 --> 00:17:38.920 So I want to show you a couple of interesting results. c8b6a59b-85a8-4447-ad90-fde8b2d3cea0-0 00:17:39.160 --> 00:17:42.178 The 1st is the story of two buildings, I like to call it at c8b6a59b-85a8-4447-ad90-fde8b2d3cea0-1 00:17:42.178 --> 00:17:42.480 least. 0a48aa52-2ad8-4c55-bd7d-882e21c56575-0 00:17:42.520 --> 00:17:46.205 So we have two buildings, one building, again designed using 0a48aa52-2ad8-4c55-bd7d-882e21c56575-1 00:17:46.205 --> 00:17:49.648 the code prescribed, two 2.5% drift limit with a few non 0a48aa52-2ad8-4c55-bd7d-882e21c56575-2 00:17:49.648 --> 00:17:53.394 structural upgrades, and then one where we just cut the drift 0a48aa52-2ad8-4c55-bd7d-882e21c56575-3 00:17:53.394 --> 00:17:54.240 limit in half. 80b38729-e8b6-4165-b2a4-33d53b34bbb6-0 00:17:55.240 --> 00:17:58.905 What's interesting about this case, and I'm showing here a 80b38729-e8b6-4165-b2a4-33d53b34bbb6-1 00:17:58.905 --> 00:18:02.509 plot when the X axis is the target time and the Y axis is 80b38729-e8b6-4165-b2a4-33d53b34bbb6-2 00:18:02.509 --> 00:18:05.926 the probability of exceeding that target time over the 80b38729-e8b6-4165-b2a4-33d53b34bbb6-3 00:18:05.926 --> 00:18:07.480 lifetime of the building. 719822e6-039d-4467-a595-bbcc1a17ac1b-0 00:18:07.800 --> 00:18:12.134 And you can think of this X axis as showing us a variety or a 719822e6-039d-4467-a595-bbcc1a17ac1b-1 00:18:12.134 --> 00:18:15.560 continuum of different performance flow metrics. 29cccce4-afc3-4dc1-8604-1f22b7318e2d-0 00:18:16.200 --> 00:18:20.457 To give you some context here, some stakeholders might say that 29cccce4-afc3-4dc1-8604-1f22b7318e2d-1 00:18:20.457 --> 00:18:24.049 my goal for this building is to to make sure that the 29cccce4-afc3-4dc1-8604-1f22b7318e2d-2 00:18:24.049 --> 00:18:28.240 probability of exceeding 7 days in 50 years is very, very low. 636da85d-9a2b-468f-9026-10647ce0f182-0 00:18:28.600 --> 00:18:31.634 And those might be folks who are working in public safety or 636da85d-9a2b-468f-9026-10647ce0f182-1 00:18:31.634 --> 00:18:32.480 hospital systems. 3a708736-318c-416f-8993-7eafef885603-0 00:18:32.480 --> 00:18:34.520 They're very concerned about those low times. 8cd5221e-f099-4b23-b784-a1a368eeed15-0 00:18:35.080 --> 00:18:38.713 Whereas maybe grocery stores, maybe more, maybe grocery stores 8cd5221e-f099-4b23-b784-a1a368eeed15-1 00:18:38.713 --> 00:18:40.040 is a less good example. f43bb1ef-9130-48c9-9e8b-3195edac4025-0 00:18:40.040 --> 00:18:41.960 I think COVID kind of showed us that they're pretty important. 2f90bef0-f51b-462f-9c94-8681e5a84a37-0 00:18:41.960 --> 00:18:45.617 But maybe like, let's say a not so important building, maybe not 2f90bef0-f51b-462f-9c94-8681e5a84a37-1 00:18:45.617 --> 00:18:49.330 necessarily this building, maybe some other building that is far, 2f90bef0-f51b-462f-9c94-8681e5a84a37-2 00:18:49.330 --> 00:18:50.400 far less important. d38caeb8-0661-4fb6-adc7-2e667665c075-0 00:18:51.400 --> 00:18:51.560 OK. 90b5c6ca-f5e9-4664-b061-246c78689ff9-0 00:18:52.040 --> 00:18:55.869 That building maybe somewhere here is acceptable for society, 90b5c6ca-f5e9-4664-b061-246c78689ff9-1 00:18:55.869 --> 00:18:56.240 right? 9f0c041b-ef57-482f-86ae-f00b24de768f-0 00:18:56.680 --> 00:19:00.280 But those are two different ways of expressing lifetime risk. 352d465b-1099-4aab-990e-d61c257ad20a-0 00:19:00.600 --> 00:19:03.934 And what we saw in this experiment is that at 120 days, 352d465b-1099-4aab-990e-d61c257ad20a-1 00:19:03.934 --> 00:19:07.448 if you look at that plot, the probability of exceeding 120 352d465b-1099-4aab-990e-d61c257ad20a-2 00:19:07.448 --> 00:19:11.021 days for both of these buildings that have been improved in 352d465b-1099-4aab-990e-d61c257ad20a-3 00:19:11.021 --> 00:19:13.880 different ways is identical, is limited to 20%. 7612add6-bd92-4669-8685-df78c2ecb8c4-0 00:19:14.400 --> 00:19:17.836 Now what is interesting is that depending on the intervention, 7612add6-bd92-4669-8685-df78c2ecb8c4-1 00:19:17.836 --> 00:19:21.000 the performance either less than or greater than changes. e3a7ea9f-09da-4fc3-84a2-f4edbc9600d6-0 00:19:21.440 --> 00:19:25.046 So that building that has been improved non structurally e3a7ea9f-09da-4fc3-84a2-f4edbc9600d6-1 00:19:25.046 --> 00:19:28.652 outperforms the stiffened building at lower target times e3a7ea9f-09da-4fc3-84a2-f4edbc9600d6-2 00:19:28.652 --> 00:19:31.120 and the trend reverses after 120 days. 6ae46b52-4678-4371-8ef3-5d240a824ebb-0 00:19:31.120 --> 00:19:33.940 And you can think of this intuitively as at lower target 6ae46b52-4678-4371-8ef3-5d240a824ebb-1 00:19:33.940 --> 00:19:36.612 times things that impede function, things that impede 6ae46b52-4678-4371-8ef3-5d240a824ebb-2 00:19:36.612 --> 00:19:37.800 reoccupancy matter more. b8860bee-c7cf-46e3-baf9-8c9a0fd57f2b-0 00:19:38.080 --> 00:19:41.920 For example, can can inhabitants come back into the building? d206cb8a-b2dc-4a29-b631-be6a194a09a1-0 00:19:42.160 --> 00:19:45.120 Is the envelope, is the envelope intact? 410a134d-c82b-4d26-a3a7-d08538a1f864-0 00:19:45.400 --> 00:19:47.884 Whereas at longer times we're looking at collapse or 410a134d-c82b-4d26-a3a7-d08538a1f864-1 00:19:47.884 --> 00:19:50.275 irreparable damage that are really governed by, by 410a134d-c82b-4d26-a3a7-d08538a1f864-2 00:19:50.275 --> 00:19:51.400 structural enhancements. 356399c1-322c-4f52-b2ba-388b688dd63c-0 00:19:51.400 --> 00:19:54.120 And that's why that stiffen building outperforms there. 4ecb2fb9-b4a9-4089-950f-1716ba99f38d-0 00:19:54.680 --> 00:19:56.360 But we didn't stop at 2 buildings. 84ee5a25-db32-4daf-9cb7-96ad87cd1525-0 00:19:56.360 --> 00:19:59.132 We repeated this for 10,000 buildings to see is this an edge 84ee5a25-db32-4daf-9cb7-96ad87cd1525-1 00:19:59.132 --> 00:19:59.360 case? 2578f3de-0e71-45ce-9aba-5288a21e8cf3-0 00:19:59.360 --> 00:20:00.520 You know, is there a trend here? b184e7ff-25e3-4af6-8e75-8192433a80d5-0 00:20:01.040 --> 00:20:04.851 And so we went in and we, we took the entire set of results b184e7ff-25e3-4af6-8e75-8192433a80d5-1 00:20:04.851 --> 00:20:08.600 and we explored correlations between two types of metrics. 737b9ff1-54fe-40bc-9b2b-335185dc023a-0 00:20:08.600 --> 00:20:12.764 So the first 2 are the same that we saw before, probability of 737b9ff1-54fe-40bc-9b2b-335185dc023a-1 00:20:12.764 --> 00:20:14.880 exceeding 120 days and 50 years. b466e24d-4d15-4ecc-b212-e9b0f6c7e955-0 00:20:15.240 --> 00:20:19.227 And then on the Y axis, another metric denoted as the expected b466e24d-4d15-4ecc-b212-e9b0f6c7e955-1 00:20:19.227 --> 00:20:20.240 annual downtime. c32068ea-cb72-4959-b713-e771f5ea6a32-0 00:20:20.240 --> 00:20:23.320 This is an annualized metric similar to expected annual loss. da1ce455-486e-443e-b755-ef8c70f1c82e-0 00:20:23.720 --> 00:20:27.138 That's meant to be a holistic metric that kind of takes da1ce455-486e-443e-b755-ef8c70f1c82e-1 00:20:27.138 --> 00:20:28.360 everything together. 5daeff67-a014-4517-a84f-d780a35e2394-0 00:20:28.760 --> 00:20:31.800 And what we found is that they're very well correlated. 562d381b-fbd8-425d-a82d-030bee357623-0 00:20:32.160 --> 00:20:35.890 And it was, it's, it's not a a coincidence that if we look at 562d381b-fbd8-425d-a82d-030bee357623-1 00:20:35.890 --> 00:20:39.199 this 20% mark, which is essentially that 20% we saw on 562d381b-fbd8-425d-a82d-030bee357623-2 00:20:39.199 --> 00:20:42.568 the last slide and these two icons representing the two 562d381b-fbd8-425d-a82d-030bee357623-3 00:20:42.568 --> 00:20:46.359 archetypes that I showed you in the last slide, they're pretty 562d381b-fbd8-425d-a82d-030bee357623-4 00:20:46.359 --> 00:20:46.719 close. 4939dad7-eee2-41af-a151-debefc2487e1-0 00:20:47.040 --> 00:20:50.927 But the trend is that in general using one metric and using the 4939dad7-eee2-41af-a151-debefc2487e1-1 00:20:50.927 --> 00:20:53.600 other could be potentially interchangeable. b6228b4a-505e-447a-85af-d1df9933c767-0 00:20:54.360 --> 00:20:57.848 But if we take a look at another example, which I kind of hinted b6228b4a-505e-447a-85af-d1df9933c767-1 00:20:57.848 --> 00:21:01.014 at earlier, if we look at say probability of exceeding 120 b6228b4a-505e-447a-85af-d1df9933c767-2 00:21:01.014 --> 00:21:03.911 days in 50 years and the probably of exceeding just a b6228b4a-505e-447a-85af-d1df9933c767-3 00:21:03.911 --> 00:21:07.399 week, we find that actually they are not very correlated at all. e27bd215-132c-4478-97e3-8fac36f5e745-0 00:21:07.960 --> 00:21:11.235 And what is interesting from this, and I think the key take e27bd215-132c-4478-97e3-8fac36f5e745-1 00:21:11.235 --> 00:21:14.675 away is that we need to be very careful about where we set the e27bd215-132c-4478-97e3-8fac36f5e745-2 00:21:14.675 --> 00:21:18.005 goal posts because success in one metric may not necessarily e27bd215-132c-4478-97e3-8fac36f5e745-3 00:21:18.005 --> 00:21:19.480 lead to success in another. 14246e19-e839-47aa-97ed-de37cb477b4c-0 00:21:19.720 --> 00:21:22.444 And if we are optimizing for one, we're going to lead to 14246e19-e839-47aa-97ed-de37cb477b4c-1 00:21:22.444 --> 00:21:25.217 interventions that are totally ensuring we guarantee that 14246e19-e839-47aa-97ed-de37cb477b4c-2 00:21:25.217 --> 00:21:25.599 outcome. d414f327-8477-4dfa-af84-84a577831b2e-0 00:21:25.600 --> 00:21:29.132 And we want to make sure that we are not forgetting blind spots d414f327-8477-4dfa-af84-84a577831b2e-1 00:21:29.132 --> 00:21:29.960 that may occur. 755cff1a-cc39-4ac4-962d-c5922a8d80dc-0 00:21:30.520 --> 00:21:33.744 So overall, the study gave us a few important insights, but 755cff1a-cc39-4ac4-962d-c5922a8d80dc-1 00:21:33.744 --> 00:21:35.840 those are all geared towards the goal. b56df4ef-0717-44d5-add3-e13a739f5b03-0 00:21:35.960 --> 00:21:37.840 Now I want to shift focus towards the check. 6aaa7ef4-6cb8-4e37-9ed3-9f69dc04bb3f-0 00:21:37.840 --> 00:21:41.054 And if you guys remember, what we're thinking about are how we 6aaa7ef4-6cb8-4e37-9ed3-9f69dc04bb3f-1 00:21:41.054 --> 00:21:44.268 design checking procedures that lead to the highest confidence 6aaa7ef4-6cb8-4e37-9ed3-9f69dc04bb3f-2 00:21:44.268 --> 00:21:47.075 that the goal is being met, because when we're doing a 6aaa7ef4-6cb8-4e37-9ed3-9f69dc04bb3f-3 00:21:47.075 --> 00:21:49.320 check, we're only looking at one intensity. 0275e2e1-4d41-4567-9991-98d5d4a41afa-0 00:21:49.720 --> 00:21:53.530 And so the question is, in light of this issue that we're only 0275e2e1-4d41-4567-9991-98d5d4a41afa-1 00:21:53.530 --> 00:21:57.160 checking one point, how do we design or calibrated a check? 22c9738d-5c3e-472f-8f7c-7414e244c219-0 00:21:57.160 --> 00:22:00.759 Specifically, how do we choose this point on the curve to to 22c9738d-5c3e-472f-8f7c-7414e244c219-1 00:22:00.759 --> 00:22:03.945 check that will lead to the highest confidence that a 22c9738d-5c3e-472f-8f7c-7414e244c219-2 00:22:03.945 --> 00:22:05.480 generic goal is being met. eec868e7-f37f-4961-8ad4-ebd82391987c-0 00:22:06.040 --> 00:22:09.013 So we did this in a slightly different way to gauge the eec868e7-f37f-4961-8ad4-ebd82391987c-1 00:22:09.013 --> 00:22:12.200 efficacy, I'm calling it, of different checking procedures. da8da5bf-2e77-4166-b234-ef49bf82bbc1-0 00:22:12.440 --> 00:22:15.360 We performed a large set of fragility based assessments. 5d95fd44-b72b-47ab-9cdc-db19ba03c74a-0 00:22:15.360 --> 00:22:18.198 So we're no longer doing E 58, we're no longer doing building 5d95fd44-b72b-47ab-9cdc-db19ba03c74a-1 00:22:18.198 --> 00:22:19.160 specific assessments. 3b544913-6087-47df-a378-b65e36e623fa-0 00:22:19.160 --> 00:22:22.899 We're just using fragility curves that can accommodate a 3b544913-6087-47df-a378-b65e36e623fa-1 00:22:22.899 --> 00:22:26.704 large variety of building taxonomies and, and I guess you 3b544913-6087-47df-a378-b65e36e623fa-2 00:22:26.704 --> 00:22:29.000 could say building configurations. 173070fb-cb26-45aa-b234-b913c798aa86-0 00:22:29.400 --> 00:22:32.717 And so we begin this by starting with what we would, you know, 173070fb-cb26-45aa-b234-b913c798aa86-1 00:22:32.717 --> 00:22:34.560 realistically change with a check. 4abcde53-6598-4eb0-a3c2-d97bb07cd4f2-0 00:22:34.840 --> 00:22:37.575 And you can think of it just to kind of provide some context 4abcde53-6598-4eb0-a3c2-d97bb07cd4f2-1 00:22:37.575 --> 00:22:37.800 here. 98ee69db-8eda-401c-8b8d-a98929323280-0 00:22:38.200 --> 00:22:41.709 There are conversations in the structural engineering community 98ee69db-8eda-401c-8b8d-a98929323280-1 00:22:41.709 --> 00:22:45.165 as to whether or not we should be checking performance using a 98ee69db-8eda-401c-8b8d-a98929323280-2 00:22:45.165 --> 00:22:46.920 median functional recovery time. 7f8dc804-d15e-4fbe-ac25-eabc6243ea73-0 00:22:47.280 --> 00:22:51.073 A median functional recovery time, you can think of it as a, 7f8dc804-d15e-4fbe-ac25-eabc6243ea73-1 00:22:51.073 --> 00:22:54.805 a threshold or a point on the fragility curve equivalent to 7f8dc804-d15e-4fbe-ac25-eabc6243ea73-2 00:22:54.805 --> 00:22:57.479 50%, like a 50% probability of exceedance. f978891d-da5d-4968-95c5-1ffb88aec10a-0 00:22:57.800 --> 00:23:00.599 There are other engineers who say I want to be checking that f978891d-da5d-4968-95c5-1ffb88aec10a-1 00:23:00.599 --> 00:23:03.536 we have exceeded a target time using the 90th percentile, which f978891d-da5d-4968-95c5-1ffb88aec10a-2 00:23:03.536 --> 00:23:06.105 would get you down to the 10th percentile point on that f978891d-da5d-4968-95c5-1ffb88aec10a-3 00:23:06.105 --> 00:23:06.840 fertility curve. 05cba82f-e656-4919-be44-37565e3b8a2e-0 00:23:07.080 --> 00:23:08.560 That's where all of this is coming from. 27d4d502-d7c5-407b-b41d-988962472790-0 00:23:08.920 --> 00:23:13.579 And So what we did is we started with just the checking procedure 27d4d502-d7c5-407b-b41d-988962472790-1 00:23:13.579 --> 00:23:17.745 and varied this this threshold Y that we saw on the on the 27d4d502-d7c5-407b-b41d-988962472790-2 00:23:17.745 --> 00:23:19.440 fertility curve earlier. b543f19a-ef45-4952-8f4e-7cbc02a89724-0 00:23:20.000 --> 00:23:24.652 Then we said, OK, let's specify different values of Z that is b543f19a-ef45-4952-8f4e-7cbc02a89724-1 00:23:24.652 --> 00:23:28.480 the acceptable probability of failure in 50 years. 7b7599af-09ef-4eff-8e8b-c5af04fbcd93-0 00:23:28.680 --> 00:23:30.440 We can think of this also as a risk target. 82f17222-d029-4dcc-9c34-b77bd6930e00-0 00:23:30.480 --> 00:23:31.360 Let's change that. 36b181eb-205d-4431-acd1-3dbf0b1d11d0-0 00:23:32.160 --> 00:23:35.239 And then let's also change the site at which we are doing the 36b181eb-205d-4431-acd1-3dbf0b1d11d0-1 00:23:35.239 --> 00:23:36.680 risk targeting or the design. 37808e3f-a3d9-483e-a3d8-287b3a0eb2c6-0 00:23:37.520 --> 00:23:42.360 Then what we do is using LUCO 2007 simple risk targeting, we 37808e3f-a3d9-483e-a3d8-287b3a0eb2c6-1 00:23:42.360 --> 00:23:47.439 go in and we figure out what is the, what is the intensity that 37808e3f-a3d9-483e-a3d8-287b3a0eb2c6-2 00:23:47.439 --> 00:23:52.360 would yield the performance goal and based on the selected Y. 86320a18-ccc6-4555-bed5-d52a2b8cabd2-0 00:23:52.360 --> 00:23:55.760 So this is giving you a sense of what that risk targeting does. 727218e2-a8b4-470e-88c4-a2a9a6f40795-0 00:23:55.760 --> 00:23:56.840 It gives you this intensity. 8cc6f43d-c265-4683-a441-4c6b79ab92cb-0 00:23:57.160 --> 00:24:00.352 And then we're using a beta for risk targeting of 0.6, I 8cc6f43d-c265-4683-a441-4c6b79ab92cb-1 00:24:00.352 --> 00:24:00.800 believe. f94db733-c73b-4ffb-963f-6a7a5b04f319-0 00:24:01.120 --> 00:24:02.960 And then what we're doing is just varying the shape. 0404ac16-ab37-42f4-bb8e-5aac9022b918-0 00:24:03.280 --> 00:24:06.159 So we're saying, OK, let's pinch this part of the curve, and then 0404ac16-ab37-42f4-bb8e-5aac9022b918-1 00:24:06.159 --> 00:24:08.819 let's change the curve in other locations to accommodate the 0404ac16-ab37-42f4-bb8e-5aac9022b918-2 00:24:08.819 --> 00:24:11.611 fact that if you're checking in one place, ultimately there may 0404ac16-ab37-42f4-bb8e-5aac9022b918-3 00:24:11.611 --> 00:24:13.879 be differences in other parts of the agility curve. 13a638c2-8118-4eb5-adc2-772b74f272af-0 00:24:14.440 --> 00:24:18.034 Then we go in and we compute the coefficient of variation on the 13a638c2-8118-4eb5-adc2-772b74f272af-1 00:24:18.034 --> 00:24:21.462 probability of failure in 50 years considering the difference 13a638c2-8118-4eb5-adc2-772b74f272af-2 00:24:21.462 --> 00:24:21.960 in shape. b21ce2eb-d84b-49aa-a178-97ebb2c13d61-0 00:24:22.920 --> 00:24:26.582 And so if we do this across many different sites, many different b21ce2eb-d84b-49aa-a178-97ebb2c13d61-1 00:24:26.582 --> 00:24:29.963 values of YIE, different checks and different goals, we can b21ce2eb-d84b-49aa-a178-97ebb2c13d61-2 00:24:29.963 --> 00:24:32.780 start to develop some relationships about what it b21ce2eb-d84b-49aa-a178-97ebb2c13d61-3 00:24:32.780 --> 00:24:35.880 means to have a good check in the context of recovery. 3b63b376-e946-4864-8114-67df979206b7-0 00:24:36.360 --> 00:24:38.980 So I'll show you an example here that is relevant for the 3b63b376-e946-4864-8114-67df979206b7-1 00:24:38.980 --> 00:24:41.600 conversations I was mentioning with structural engineers. 11efc530-a9d4-44f2-998b-0a881371cd1b-0 00:24:42.080 --> 00:24:43.120 Let's start with the goal. a620259d-0fe9-4c36-a29f-ced897dc066d-0 00:24:43.560 --> 00:24:46.953 The goal, which is one that has been pitched in the BSSC, for a620259d-0fe9-4c36-a29f-ced897dc066d-1 00:24:46.953 --> 00:24:50.292 example, at one point is to limit the probability of failure a620259d-0fe9-4c36-a29f-ced897dc066d-2 00:24:50.292 --> 00:24:51.880 in 50 years to less than 20%. b264e26f-83cf-4b79-8ee0-f3b1f73bbb05-0 00:24:52.400 --> 00:24:55.280 OK, now let's say what is it? 6d40a5e3-598b-4ea6-b5df-14adaea75f6a-0 00:24:55.320 --> 00:24:58.432 Let's ask ourselves what could be a good check to fulfill this 6d40a5e3-598b-4ea6-b5df-14adaea75f6a-1 00:24:58.432 --> 00:24:58.680 goal? 273e1cd8-e4d6-4760-8112-f720abcad386-0 00:24:59.040 --> 00:25:02.889 Well, some of you might say, let's use the median and some of 273e1cd8-e4d6-4760-8112-f720abcad386-1 00:25:02.889 --> 00:25:06.739 you might say, let's use the 90th percentile or limit the the 273e1cd8-e4d6-4760-8112-f720abcad386-2 00:25:06.739 --> 00:25:09.719 probability, the failure probability to to 10%. 3a7ddede-df7b-44c4-b7dd-61f2948f604c-0 00:25:10.280 --> 00:25:13.140 So you can see that depending on that decision, fragility curves 3a7ddede-df7b-44c4-b7dd-61f2948f604c-1 00:25:13.140 --> 00:25:13.800 look different. f037310d-8458-43f6-a06b-09255a4e14ca-0 00:25:14.240 --> 00:25:17.774 And we repeat this experiment for a variety of sites and we f037310d-8458-43f6-a06b-09255a4e14ca-1 00:25:17.774 --> 00:25:20.720 assess the coefficient of variation at each site. 3bc9d157-830a-46d5-b5e3-856793fa2243-0 00:25:21.000 --> 00:25:22.400 So I'm going to show you guys the result. 962a948e-1663-495f-ba6b-7431bbb24bd3-0 00:25:22.800 --> 00:25:25.489 But what I'll say is, is that if you use a higher conditional 962a948e-1663-495f-ba6b-7431bbb24bd3-1 00:25:25.489 --> 00:25:28.265 probability of failure, you in general get less confidence that 962a948e-1663-495f-ba6b-7431bbb24bd3-2 00:25:28.265 --> 00:25:29.480 the performance will is met. b03ba437-007a-4e07-bfc5-fd458971e988-0 00:25:29.800 --> 00:25:32.590 I want you to pay attention to this orange curve that b03ba437-007a-4e07-bfc5-fd458971e988-1 00:25:32.590 --> 00:25:35.896 represents using the median and this blue curve that represents b03ba437-007a-4e07-bfc5-fd458971e988-2 00:25:35.896 --> 00:25:37.240 using the 90th percentile. 350285b7-e691-4467-b6f8-abc060afeaab-0 00:25:37.680 --> 00:25:38.880 And then I'll show you the results. 05e78cbb-e326-4a9a-bdce-1537f40e933f-0 00:25:38.880 --> 00:25:42.559 Here the Y axis is the coefficient of variation on the 05e78cbb-e326-4a9a-bdce-1537f40e933f-1 00:25:42.559 --> 00:25:46.640 probability of failure in 50 years, IE our performance goal. 7240e5ff-cf58-497a-87ee-d4e76cf5ede9-0 00:25:46.920 --> 00:25:48.880 And then here on the X axis, I'm showing the site. a0fd6c01-2b22-47cf-af16-e03857069826-0 00:25:49.120 --> 00:25:52.783 These ZS are the same 34 sites that were used in E HERP 2015, a0fd6c01-2b22-47cf-af16-e03857069826-1 00:25:52.783 --> 00:25:54.320 and these are the results. cb2b9663-82af-46fb-b9e9-980d8e19e131-0 00:25:54.720 --> 00:25:59.628 So you can see that for the 34 sites, for the blue curve, we've cb2b9663-82af-46fb-b9e9-980d8e19e131-1 00:25:59.628 --> 00:26:04.152 limited the coefficient of variation to roughly on average cb2b9663-82af-46fb-b9e9-980d8e19e131-2 00:26:04.152 --> 00:26:06.760 10% no matter what site you pick. 184e5671-12a7-434f-9632-753e06a51db1-0 00:26:07.080 --> 00:26:10.617 Whereas there is significant variation when you're using AY 184e5671-12a7-434f-9632-753e06a51db1-1 00:26:10.617 --> 00:26:14.096 of 0.5 across the different sites, the average is actually 184e5671-12a7-434f-9632-753e06a51db1-2 00:26:14.096 --> 00:26:15.040 more than two X. 0c64ca4d-4872-41d7-ac7d-c4d958167b34-0 00:26:15.400 --> 00:26:18.950 And what you can really, I think the meaningful take away here is 0c64ca4d-4872-41d7-ac7d-c4d958167b34-1 00:26:18.950 --> 00:26:22.501 that if we are going to pick 1.2 on the fragility curve to make a 0c64ca4d-4872-41d7-ac7d-c4d958167b34-2 00:26:22.501 --> 00:26:25.783 check for recovery, we probably don't want to be picking the 0c64ca4d-4872-41d7-ac7d-c4d958167b34-3 00:26:25.783 --> 00:26:26.160 medium. 118dfb32-3748-436f-8607-37e303e220a6-0 00:26:26.720 --> 00:26:30.520 And we repeated this for a variety of different cases. bf60b641-3672-4301-bc6b-140fb4bb5a9c-0 00:26:30.720 --> 00:26:33.617 And then we actually took the average across all of the sites bf60b641-3672-4301-bc6b-140fb4bb5a9c-1 00:26:33.617 --> 00:26:34.880 and these were the results. 2f90aa8f-ce0d-41fc-9d3d-f4794b890d44-0 00:26:35.480 --> 00:26:38.206 The results on this Y axis are showing the point of the 2f90aa8f-ce0d-41fc-9d3d-f4794b890d44-1 00:26:38.206 --> 00:26:41.128 fragility we're checking, so the conditional probability of 2f90aa8f-ce0d-41fc-9d3d-f4794b890d44-2 00:26:41.128 --> 00:26:42.199 failure for the check. 838ef2a6-f861-4014-9c37-b9935e1a285c-0 00:26:42.640 --> 00:26:45.711 And then the Y axis is showing mean coefficient of variation 838ef2a6-f861-4014-9c37-b9935e1a285c-1 00:26:45.711 --> 00:26:46.920 across all of the sites. f0b7b277-19f2-42c6-a207-1b6a74f64be0-0 00:26:47.360 --> 00:26:51.111 And what we find is that there's kind of this magical location f0b7b277-19f2-42c6-a207-1b6a74f64be0-1 00:26:51.111 --> 00:26:54.684 where basically if we're using AY of 0.1, it doesn't really f0b7b277-19f2-42c6-a207-1b6a74f64be0-2 00:26:54.684 --> 00:26:57.840 matter what the performance goal is, what that C is. 81ca4b91-bb19-4926-a935-f28c627f53bb-0 00:26:58.000 --> 00:27:01.329 We are consistently getting a, an average coefficient of 81ca4b91-bb19-4926-a935-f28c627f53bb-1 00:27:01.329 --> 00:27:05.009 variation that is lower than, I would say, many points on this 81ca4b91-bb19-4926-a935-f28c627f53bb-2 00:27:05.009 --> 00:27:05.360 curve. 306c8e04-09a0-435f-ae72-594ce594bdde-0 00:27:05.760 --> 00:27:09.568 And interestingly, if we look at the second most popular place 306c8e04-09a0-435f-ae72-594ce594bdde-1 00:27:09.568 --> 00:27:13.073 that engineers are discussing, which is the a conditional 306c8e04-09a0-435f-ae72-594ce594bdde-2 00:27:13.073 --> 00:27:17.063 probability of failure of 50% or using the median to check, there 306c8e04-09a0-435f-ae72-594ce594bdde-3 00:27:17.063 --> 00:27:20.810 is a significant dependency on the efficacy of the check as a 306c8e04-09a0-435f-ae72-594ce594bdde-4 00:27:20.810 --> 00:27:24.014 function of the risk target, where the more the less 306c8e04-09a0-435f-ae72-594ce594bdde-5 00:27:24.014 --> 00:27:27.520 ambitious you go, the lower the coefficient of variation. bd132eda-6b15-4780-9f83-83100e26f506-0 00:27:27.520 --> 00:27:31.034 But obviously many values of Z that are being discussed are, bd132eda-6b15-4780-9f83-83100e26f506-1 00:27:31.034 --> 00:27:32.360 you know, .2, maybe .1. ece2f30e-b8f9-44af-a650-cd49ebafcf63-0 00:27:32.680 --> 00:27:35.536 And so you can see that coefficient of variation, you ece2f30e-b8f9-44af-a650-cd49ebafcf63-1 00:27:35.536 --> 00:27:37.600 know, increased by a significant deal. 93af898c-4028-43ae-a3ae-62aa8849f4d0-0 00:27:37.960 --> 00:27:41.082 So actually right now at the BSSC for context, I think that 93af898c-4028-43ae-a3ae-62aa8849f4d0-1 00:27:41.082 --> 00:27:44.100 they're, they're currently looking for a place between 10 93af898c-4028-43ae-a3ae-62aa8849f4d0-2 00:27:44.100 --> 00:27:47.431 and 25% that represent, I think some of the more stable regions 93af898c-4028-43ae-a3ae-62aa8849f4d0-3 00:27:47.431 --> 00:27:48.159 of this curve. c718b087-603c-47ac-85db-a12c28cc06d1-0 00:27:48.600 --> 00:27:51.418 So in terms of research contributions, we talked about c718b087-603c-47ac-85db-a12c28cc06d1-1 00:27:51.418 --> 00:27:51.880 the goal. cac6ac3e-072f-49e4-a1b5-078fa6bb3fd7-0 00:27:52.120 --> 00:27:54.366 We're expressing the goal in terms of a probability of cac6ac3e-072f-49e4-a1b5-078fa6bb3fd7-1 00:27:54.366 --> 00:27:55.960 failure in 50 years to be less than Z. 782c7f31-f542-4b3e-9359-a68cb5e75da0-0 00:27:56.240 --> 00:27:58.992 We talked about a check how that is looking at one point on the 782c7f31-f542-4b3e-9359-a68cb5e75da0-1 00:27:58.992 --> 00:27:59.680 fragility curve. 406ec575-a9c3-476c-a6e9-20c4c5b6a1a8-0 00:28:00.000 --> 00:28:03.457 And in general, the performance objectives for recovery should 406ec575-a9c3-476c-a6e9-20c4c5b6a1a8-1 00:28:03.457 --> 00:28:06.640 be defined in terms of the goal and a checking procedure. 6a450213-f8fa-4c06-a477-7b7a9cb7c6fd-0 00:28:06.920 --> 00:28:09.685 We saw a correlation study that showed not all performance full 6a450213-f8fa-4c06-a477-7b7a9cb7c6fd-1 00:28:09.685 --> 00:28:10.680 metrics are correlated. b24c85aa-3d91-41ab-a51e-4b55c1e0d10c-0 00:28:10.960 --> 00:28:13.860 And then finally, using fragility assessments that use b24c85aa-3d91-41ab-a51e-4b55c1e0d10c-1 00:28:13.860 --> 00:28:17.181 the conditional probability of failure between 10 and 20% that b24c85aa-3d91-41ab-a51e-4b55c1e0d10c-2 00:28:17.181 --> 00:28:20.134 we just saw in the previous slide, we can significantly b24c85aa-3d91-41ab-a51e-4b55c1e0d10c-3 00:28:20.134 --> 00:28:23.614 improve the efficacy of a design check regardless of the selected b24c85aa-3d91-41ab-a51e-4b55c1e0d10c-4 00:28:23.614 --> 00:28:24.880 performance goal target. 6833b94e-ef02-4fbc-be45-633d586997a2-0 00:28:25.400 --> 00:28:27.320 So that was all about the goal. c0954e31-2e91-4cf0-9539-dcce8138e3ee-0 00:28:27.880 --> 00:28:30.297 In the next part of the presentation, I want to switch c0954e31-2e91-4cf0-9539-dcce8138e3ee-1 00:28:30.297 --> 00:28:31.440 gears to how we get there. b8520b18-a3b3-4a56-a451-9abe60718ba4-0 00:28:31.680 --> 00:28:33.440 You might ask me, well, Omar, that's all great. fbfec762-a5c0-4c13-897d-74e97724e2db-0 00:28:33.440 --> 00:28:35.920 And those are a lot of curves, but like what do we have to do fbfec762-a5c0-4c13-897d-74e97724e2db-1 00:28:35.920 --> 00:28:38.240 with these buildings to actually achieve achieve recovery fbfec762-a5c0-4c13-897d-74e97724e2db-2 00:28:38.240 --> 00:28:38.720 performance? 1b0f42c6-9d6d-48ec-870e-f7f95ccb81f0-0 00:28:39.040 --> 00:28:42.845 So this part of the study I actually did with Doctor Rodrigo 1b0f42c6-9d6d-48ec-870e-f7f95ccb81f0-1 00:28:42.845 --> 00:28:45.840 Silva Lopez and Professor Henry Burton at UCLA. 38be8532-a9fc-45f4-b978-f1d606db684b-0 00:28:46.920 --> 00:28:49.880 And so to begin this, I just want us to take a field trip. 3003fda3-2ee7-4e2e-bf08-76016e9c864a-0 00:28:49.880 --> 00:28:52.950 So let's take a look at the front cover of the New York 3003fda3-2ee7-4e2e-bf08-76016e9c864a-1 00:28:52.950 --> 00:28:53.280 Times. fafc2f39-9d82-45ae-975c-1e81c3a706e3-0 00:28:53.280 --> 00:28:56.196 I absolutely love this this this cover of the New York Times fafc2f39-9d82-45ae-975c-1e81c3a706e3-1 00:28:56.196 --> 00:28:59.113 because it's very rare they talk about, you know, earthquake fafc2f39-9d82-45ae-975c-1e81c3a706e3-2 00:28:59.113 --> 00:28:59.640 resilience. cba64851-88f7-49a8-8758-476fb421328f-0 00:28:59.640 --> 00:29:00.760 So I thought it was pretty cool. 9c1c4441-ef88-4b1a-8415-c8b5f971b2d2-0 00:29:01.120 --> 00:29:03.416 Here they're showing the Oregon State Treasury building that I 9c1c4441-ef88-4b1a-8415-c8b5f971b2d2-1 00:29:03.416 --> 00:29:04.400 mentioned you guys earlier. acef22c2-2d52-48f7-a1aa-de9bb4df226c-0 00:29:04.760 --> 00:29:05.920 It's a very beautiful building. 585106e1-3102-4396-9a7a-770733c74d89-0 00:29:06.280 --> 00:29:09.547 It's base isolated with up to 18 inches of horizontal movement in 585106e1-3102-4396-9a7a-770733c74d89-1 00:29:09.547 --> 00:29:10.240 any direction. 89ec80c9-f763-44ba-a299-b1b573671c1c-0 00:29:10.280 --> 00:29:13.639 And if we take a cut in the middle, we can start to see some 89ec80c9-f763-44ba-a299-b1b573671c1c-1 00:29:13.639 --> 00:29:16.724 examples of innovative structural detailing that led to 89ec80c9-f763-44ba-a299-b1b573671c1c-2 00:29:16.724 --> 00:29:17.440 this outcome. f6c2b497-0e99-443f-af93-198e67feda66-0 00:29:17.920 --> 00:29:20.446 First, obviously is the base isolation that's a structural f6c2b497-0e99-443f-af93-198e67feda66-1 00:29:20.446 --> 00:29:20.960 improvement. 3cb4f08a-20cf-4b7f-89d6-855bb0a69b36-0 00:29:21.360 --> 00:29:24.675 The second is the high performance glass and facade 3cb4f08a-20cf-4b7f-89d6-855bb0a69b36-1 00:29:24.675 --> 00:29:28.627 elements on the exterior that are resisting, I mean excessive 3cb4f08a-20cf-4b7f-89d6-855bb0a69b36-2 00:29:28.627 --> 00:29:29.520 storage rates. d5261f7d-83c6-4291-82dd-adb2bb7c938c-0 00:29:29.920 --> 00:29:32.440 And then the third is you notice these are very clean ceilings. 449ae419-e125-4489-b940-83ebf123b3e6-0 00:29:32.680 --> 00:29:35.634 There's not a whole lot of things that can break, which is 449ae419-e125-4489-b940-83ebf123b3e6-1 00:29:35.634 --> 00:29:38.738 often one of the things that impedes return to function after 449ae419-e125-4489-b940-83ebf123b3e6-2 00:29:38.738 --> 00:29:39.840 a after an earthquake. 67e9698e-455e-4d86-ba1c-cb5d941a0ecb-0 00:29:39.840 --> 00:29:41.400 I know you guys are looking at the ceiling right now. 710d3b8e-2366-40f1-bf13-e28cfebcb7de-0 00:29:42.000 --> 00:29:45.920 There are some things here I wouldn't need to worry though. 4097626e-03d6-4b49-84f1-3468540ab46d-0 00:29:45.920 --> 00:29:49.202 But yeah, so this building is a great example of of how we 4097626e-03d6-4b49-84f1-3468540ab46d-1 00:29:49.202 --> 00:29:50.760 achieve functional recovery. 51f915cb-3031-4d92-a2e9-dfeb5d5f0c6d-0 00:29:52.080 --> 00:29:54.735 Now in terms of the actual work, the question is how do we 51f915cb-3031-4d92-a2e9-dfeb5d5f0c6d-1 00:29:54.735 --> 00:29:56.400 generalize this across any building? f82eeb15-9dd4-4f6a-82a5-8978762017cc-0 00:29:56.400 --> 00:29:59.476 How do we know what is the efficient design strategy for f82eeb15-9dd4-4f6a-82a5-8978762017cc-1 00:29:59.476 --> 00:30:00.880 recovery for any building? a7a55999-6f8d-47d8-8ed1-51edd165adfc-0 00:30:00.960 --> 00:30:05.949 So what we did as we started with a check for a given check a7a55999-6f8d-47d8-8ed1-51edd165adfc-1 00:30:05.949 --> 00:30:10.690 and a given building at a given site, how do we find the a7a55999-6f8d-47d8-8ed1-51edd165adfc-2 00:30:10.690 --> 00:30:15.846 strategies, IE how do we find cost optimal resource efficient a7a55999-6f8d-47d8-8ed1-51edd165adfc-3 00:30:15.846 --> 00:30:21.251 strategies to achieve earthquake recovery, objective development a7a55999-6f8d-47d8-8ed1-51edd165adfc-4 00:30:21.251 --> 00:30:26.241 and provisions and engineering intuition and really support a7a55999-6f8d-47d8-8ed1-51edd165adfc-5 00:30:26.241 --> 00:30:30.400 those who are trying to do benefit cost analysis. 2ee516e7-cc56-41bc-8538-46b0620f12fc-0 00:30:30.720 --> 00:30:33.354 Anyone who's doing benefit cost analysis, their first question 2ee516e7-cc56-41bc-8538-46b0620f12fc-1 00:30:33.354 --> 00:30:34.400 is how much does it cost? b401a04c-af6b-48c8-85e0-b3814baa4bae-0 00:30:34.720 --> 00:30:37.229 Well, we can't do that if we don't have an understanding of b401a04c-af6b-48c8-85e0-b3814baa4bae-1 00:30:37.229 --> 00:30:38.400 what is an effective design. 46c841b4-158d-46ee-aabf-eb1b1253ff84-0 00:30:38.680 --> 00:30:40.480 Otherwise it undermines that analysis. fbb72529-2f25-415d-adb0-fee66ed140c1-0 00:30:40.760 --> 00:30:44.003 So I would say the big problem with today's approach is if you fbb72529-2f25-415d-adb0-fee66ed140c1-1 00:30:44.003 --> 00:30:46.681 were trying to do an optimization is that they lack fbb72529-2f25-415d-adb0-fee66ed140c1-2 00:30:46.681 --> 00:30:49.410 the computational efficiency to perform this type of fbb72529-2f25-415d-adb0-fee66ed140c1-3 00:30:49.410 --> 00:30:50.080 optimization. 123bd815-9a01-4a0b-a81c-1a9f2d6084d2-0 00:30:50.520 --> 00:30:53.320 I mentioned to you that the design space is pretty large. 6f323af9-0590-4d30-8c9b-f4faf056c446-0 00:30:53.400 --> 00:30:56.415 If we wanted to actually do this using today's approaches, we'd 6f323af9-0590-4d30-8c9b-f4faf056c446-1 00:30:56.415 --> 00:30:59.147 go and we'd start, OK, how do we improve the the building 6f323af9-0590-4d30-8c9b-f4faf056c446-2 00:30:59.147 --> 00:30:59.759 structurally? d5f3f529-fa9c-4a69-b90a-2c81a5adf362-0 00:30:59.960 --> 00:31:01.840 That's going to be maybe what's the lateral system? af326053-1ab3-43ac-b13d-be18f9a6a8be-0 00:31:02.160 --> 00:31:03.520 What's the dampers we're going to put in? ae340eab-8793-4f18-a77e-6cc5a136372d-0 00:31:03.520 --> 00:31:04.440 What's the importance factor? dc651485-b0e4-4cbe-b1aa-8a7659ced668-0 00:31:04.440 --> 00:31:05.200 What's the drift limit? 09753c0f-b6e2-40f9-be85-1251329299c9-0 00:31:05.680 --> 00:31:07.781 Then you might say, well, Omar, I want some non structural in 09753c0f-b6e2-40f9-be85-1251329299c9-1 00:31:07.781 --> 00:31:08.120 there too. b9d7b0ce-012a-4146-9e7e-eba9b96afbd6-0 00:31:08.120 --> 00:31:10.784 So we'll probably say, OK, maybe we improved a few different b9d7b0ce-012a-4146-9e7e-eba9b96afbd6-1 00:31:10.784 --> 00:31:11.920 features non structurally. 46255fda-3e0b-4ddb-ab2e-24670814100b-0 00:31:12.200 --> 00:31:14.800 Some of you might be interested in utility backup actions, 46255fda-3e0b-4ddb-ab2e-24670814100b-1 00:31:14.800 --> 00:31:16.960 Others might be interested in recovery planning. 4b962f55-48a8-4416-99f1-70a4d024a467-0 00:31:17.240 --> 00:31:19.953 For all intents and purposes, let's just put it in an array 4b962f55-48a8-4416-99f1-70a4d024a467-1 00:31:19.953 --> 00:31:20.360 called X. 83cbfd0c-d122-49ec-8393-0c1fbf105647-0 00:31:20.840 --> 00:31:22.840 So here it's in one array X. 03cafb69-f2d0-4cfb-9451-23ffc1228437-0 00:31:23.200 --> 00:31:26.703 Let's take that array and propagate it into this very 03cafb69-f2d0-4cfb-9451-23ffc1228437-1 00:31:26.703 --> 00:31:30.596 constrained needs, I guess representation of all the things 03cafb69-f2d0-4cfb-9451-23ffc1228437-2 00:31:30.596 --> 00:31:31.440 you could do. 77cc6af7-667b-48d5-a744-9f26eacbfdad-0 00:31:31.880 --> 00:31:35.104 What I would do if I were to do this optimization using today's 77cc6af7-667b-48d5-a744-9f26eacbfdad-1 00:31:35.104 --> 00:31:37.925 approaches is run a building specific performance based 77cc6af7-667b-48d5-a744-9f26eacbfdad-2 00:31:37.925 --> 00:31:41.200 assessment using the procedures I mentioned at the introduction. b9000a78-028d-4e54-97e5-fcac0c4e955f-0 00:31:41.200 --> 00:31:44.973 These are your FEMA P58 damage and loss assessment, your AATC b9000a78-028d-4e54-97e5-fcac0c4e955f-1 00:31:44.973 --> 00:31:46.800 138, the downtime assessments. 1a6b5963-4b0d-4ac1-8cd6-543c92e8d62b-0 00:31:47.120 --> 00:31:50.894 The reason why I keep mentioning ATC 138 is that FEMA P 58 alone 1a6b5963-4b0d-4ac1-8cd6-543c92e8d62b-1 00:31:50.894 --> 00:31:54.494 is only giving you component level repair times, but is in no 1a6b5963-4b0d-4ac1-8cd6-543c92e8d62b-2 00:31:54.494 --> 00:31:57.804 way accounting for realistic repair sequencing and those 1a6b5963-4b0d-4ac1-8cd6-543c92e8d62b-3 00:31:57.804 --> 00:32:01.347 impeding factors that would prevent initiation of repairs in 1a6b5963-4b0d-4ac1-8cd6-543c92e8d62b-4 00:32:01.347 --> 00:32:02.160 the 1st place. 588bafca-977c-4737-9134-e64c2ca0a0db-0 00:32:02.160 --> 00:32:05.242 These are your permitting, financing and and other things 588bafca-977c-4737-9134-e64c2ca0a0db-1 00:32:05.242 --> 00:32:08.696 that from past disasters we know impact functional recovery time 588bafca-977c-4737-9134-e64c2ca0a0db-2 00:32:08.696 --> 00:32:09.440 significantly. 81283152-17cf-4dff-b5bd-bc78119ee1a2-0 00:32:10.000 --> 00:32:12.040 So let's say we, you know, we have this all set up. 558f652e-fc58-41fe-8971-5a613c876789-0 00:32:12.400 --> 00:32:15.906 Now you would have to do this may run this maybe 10,000 times 558f652e-fc58-41fe-8971-5a613c876789-1 00:32:15.906 --> 00:32:18.960 using an objective function that you that you choose. e46962cb-cd1c-43ed-a9fe-62112a56fae4-0 00:32:18.960 --> 00:32:21.948 Some of you will be interested in cost, some of you will be e46962cb-cd1c-43ed-a9fe-62112a56fae4-1 00:32:21.948 --> 00:32:24.936 interested in materials, IE how do I achieve say a month of e46962cb-cd1c-43ed-a9fe-62112a56fae4-2 00:32:24.936 --> 00:32:27.625 downtime or a month of functional recovery time using e46962cb-cd1c-43ed-a9fe-62112a56fae4-3 00:32:27.625 --> 00:32:29.120 the lowest resources possible. 64a4a05e-9fcb-47ec-929e-6a65ff36219c-0 00:32:29.600 --> 00:32:32.886 This probably would take you maybe 2-3 days at most to do 64a4a05e-9fcb-47ec-929e-6a65ff36219c-1 00:32:32.886 --> 00:32:35.040 for, for one building it's very slow. d9d22213-fc57-493f-aa24-dd74f0a5b59c-0 00:32:35.400 --> 00:32:38.804 So what we do is we replace the entire middle part with a neural d9d22213-fc57-493f-aa24-dd74f0a5b59c-1 00:32:38.804 --> 00:32:42.000 network based surrogate model that can achieve computational d9d22213-fc57-493f-aa24-dd74f0a5b59c-2 00:32:42.000 --> 00:32:44.200 efficiency gains and orders of magnitude. dfaaaa90-ef49-4a03-a744-77288ddc39a6-0 00:32:45.120 --> 00:32:48.620 So the study which explored this idea of using a surrogate model dfaaaa90-ef49-4a03-a744-77288ddc39a6-1 00:32:48.620 --> 00:32:50.560 consisted of three core components. 9ddfb646-786e-4940-82ff-ab74eeefc69c-0 00:32:50.880 --> 00:32:53.983 The first is the optimization itself, the second is the 9ddfb646-786e-4940-82ff-ab74eeefc69c-1 00:32:53.983 --> 00:32:57.586 surrogate modeling, and then the third is what do the outputs of 9ddfb646-786e-4940-82ff-ab74eeefc69c-2 00:32:57.586 --> 00:32:59.360 such an analysis even look like? 4b45d9ea-f1ce-417a-8e2e-bb5767e8706f-0 00:32:59.800 --> 00:33:02.781 So I'll start with the 1st and I'll spare you all of the 4b45d9ea-f1ce-417a-8e2e-bb5767e8706f-1 00:33:02.781 --> 00:33:03.200 details. bf32f0d3-ade5-4a18-bdcd-a901f4dc9e76-0 00:33:03.320 --> 00:33:05.639 I will only summarize this in one slide and of course, feel bf32f0d3-ade5-4a18-bdcd-a901f4dc9e76-1 00:33:05.639 --> 00:33:07.920 free to ask me after this or dive into the paper for more. 3934a775-78c0-495e-83e7-0adfd11329fb-0 00:33:08.400 --> 00:33:12.150 But that the general framework is to start with how we design 3934a775-78c0-495e-83e7-0adfd11329fb-1 00:33:12.150 --> 00:33:15.900 buildings today at a specific site using ASE 716 and say, for 3934a775-78c0-495e-83e7-0adfd11329fb-2 00:33:15.900 --> 00:33:19.710 example, this very nice three story building achieved a median 3934a775-78c0-495e-83e7-0adfd11329fb-3 00:33:19.710 --> 00:33:23.400 functional recovery time of 155 days at the 475 year return. 1c3d86f6-e100-4f88-a679-a30c69c8738f-0 00:33:24.080 --> 00:33:27.320 Then what we would do is say, OK, I want I, let's say you have 1c3d86f6-e100-4f88-a679-a30c69c8738f-1 00:33:27.320 --> 00:33:29.480 a check in mind or a goal in mind, right? c8ec99f5-1bf8-49c0-8839-e962a37287e3-0 00:33:29.720 --> 00:33:32.320 And we've, we've defined those per the previous section. 493699cd-ca22-4a9a-9e0b-594e9f0459a2-0 00:33:32.320 --> 00:33:34.160 So we're saying, OK, my check. c1682c2a-c0e5-4981-bdca-b43da84402c6-0 00:33:34.160 --> 00:33:36.792 Now I know I told you guys don't use the median, but we're using c1682c2a-c0e5-4981-bdca-b43da84402c6-1 00:33:36.792 --> 00:33:37.440 the median here. 5b1e4127-6340-42a9-b10e-9f4ea1953735-0 00:33:37.800 --> 00:33:41.627 OK, let's achieve 30 days of functional recovery time under 5b1e4127-6340-42a9-b10e-9f4ea1953735-1 00:33:41.627 --> 00:33:42.840 the 475 year event. 50b6785e-ad01-448f-bab9-5df89a417e54-0 00:33:43.240 --> 00:33:46.611 Let's limit the probability of exceedance to 50%, IE let's use, 50b6785e-ad01-448f-bab9-5df89a417e54-1 00:33:46.611 --> 00:33:49.720 let's compare 30 with the median functional recovery time. b2b92f58-5d09-47d1-9751-d73700127065-0 00:33:50.200 --> 00:33:53.280 The next question is what is the strategy in this case? a4454e2a-d793-4e92-a8af-459385f9daff-0 00:33:53.280 --> 00:33:54.440 Let's just go non structural. 7411e766-b850-4808-b03c-2df0de129f2e-0 00:33:54.440 --> 00:33:55.840 We're not going to do anything to the structure. 6bd25590-9c12-461e-928c-484bd7e295a8-0 00:33:55.840 --> 00:33:56.760 We're not going to stiffen it. bef98f33-abd8-450b-9350-8b88bfb44f0f-0 00:33:57.040 --> 00:33:59.341 We're just going to harden specific non structural bef98f33-abd8-450b-9350-8b88bfb44f0f-1 00:33:59.341 --> 00:34:00.560 components in the building. 2335f425-85f4-4a2c-9224-950a5d80f919-0 00:34:00.560 --> 00:34:03.120 And then we're going to ask ourselves, is this feasible? 60b8551f-b4cf-438a-917a-f554dfcc2846-0 00:34:03.280 --> 00:34:06.088 There are certain interventions that simply will never get us 60b8551f-b4cf-438a-917a-f554dfcc2846-1 00:34:06.088 --> 00:34:07.040 get us to the target. d604ca09-b570-441c-8975-1f9deb1b3699-0 00:34:07.400 --> 00:34:10.235 You know, there it for specific targets, especially those that d604ca09-b570-441c-8975-1f9deb1b3699-1 00:34:10.235 --> 00:34:12.935 are ambitious, like 30 days, you're getting a lot to get to d604ca09-b570-441c-8975-1f9deb1b3699-2 00:34:12.935 --> 00:34:13.880 where you want to go. ae22aaa4-9cb7-4219-8309-e3ccbc6830b7-0 00:34:14.240 --> 00:34:16.398 And this is just to make sure that the optimization will ae22aaa4-9cb7-4219-8309-e3ccbc6830b7-1 00:34:16.398 --> 00:34:17.080 actually converge. dae6bf17-2df4-4293-be4a-01f32713ce2f-0 00:34:17.080 --> 00:34:19.880 If you if it's not feasible, you won't have a viable solution. 050a2479-dc22-45c8-963a-98d95ee3c074-0 00:34:20.360 --> 00:34:22.691 And then finally, we're going to do my favorite part, which is 050a2479-dc22-45c8-963a-98d95ee3c074-1 00:34:22.691 --> 00:34:23.320 the optimization. 8df7defb-7b52-4c8f-a789-1dce2cca9961-0 00:34:23.640 --> 00:34:25.983 And for the optimization, there's two key ingredients 8df7defb-7b52-4c8f-a789-1dce2cca9961-1 00:34:25.983 --> 00:34:26.200 here. d9ff5ecb-747e-4154-85e1-ae028ec92e2b-0 00:34:26.480 --> 00:34:29.305 The first is the objective function, which I mentioned last d9ff5ecb-747e-4154-85e1-ae028ec92e2b-1 00:34:29.305 --> 00:34:31.000 time is what are we optimizing for? 9781561a-9eda-42e1-9a6d-d5408e3c765b-0 00:34:31.280 --> 00:34:33.960 Are we optimizing for materials labor engineering? b8958c26-0b54-4efa-9df6-a147e9c0cd6e-0 00:34:34.480 --> 00:34:37.579 In this case, I unfortunately don't have an extensive database b8958c26-0b54-4efa-9df6-a147e9c0cd6e-1 00:34:37.579 --> 00:34:40.580 of cost data, which is very unfortunate because I think that b8958c26-0b54-4efa-9df6-a147e9c0cd6e-2 00:34:40.580 --> 00:34:43.039 is ultimately the thing we all are interested in. 6bb82a8d-650c-435a-a18d-191da2339018-0 00:34:43.440 --> 00:34:47.077 Instead, I have the second best thing, which is a variable 6bb82a8d-650c-435a-a18d-191da2339018-1 00:34:47.077 --> 00:34:50.653 called XI that represents the average or the shift in the 6bb82a8d-650c-435a-a18d-191da2339018-2 00:34:50.653 --> 00:34:53.921 fragility curves that we are making to each of these 6bb82a8d-650c-435a-a18d-191da2339018-3 00:34:53.921 --> 00:34:54.600 components. 7147a43c-f177-4f87-b218-82155bf87d6b-0 00:34:54.600 --> 00:34:58.761 So when I mention or I, when I say hardening in this context, 7147a43c-f177-4f87-b218-82155bf87d6b-1 00:34:58.761 --> 00:35:02.587 what I mean is that for a specific component in the FEMA 7147a43c-f177-4f87-b218-82155bf87d6b-2 00:35:02.587 --> 00:35:06.681 P58 analysis, let's say your HVAC duct, let's say your doors 7147a43c-f177-4f87-b218-82155bf87d6b-3 00:35:06.681 --> 00:35:10.440 that shift, let's say it's 1X2X3X is represented by XI. 86a3cc9e-7f75-4c67-87a9-4dc86c143acd-0 00:35:10.440 --> 00:35:13.411 So like one would mean we're doing nothing to this component, 86a3cc9e-7f75-4c67-87a9-4dc86c143acd-1 00:35:13.411 --> 00:35:15.760 3 would mean we're strengthening it three times. 202a7ce9-82d3-499d-bbf9-33f000200b98-0 00:35:16.080 --> 00:35:18.720 And then N represents the number of components in the building. deec2c0a-64e8-49e0-b620-490600ff7512-0 00:35:18.720 --> 00:35:22.320 In this case, we have 36 in this model, 36 unique components. da9a40c2-f542-4cea-bb59-5cf5f40bceb3-0 00:35:23.080 --> 00:35:25.995 And then 1 / N is basically saying, let's take the average da9a40c2-f542-4cea-bb59-5cf5f40bceb3-1 00:35:25.995 --> 00:35:27.280 of all these improvements. ab561574-0e56-4e6d-a75b-bcabe370f1e9-0 00:35:27.640 --> 00:35:31.350 You can think of it also as like an importance factor for these ab561574-0e56-4e6d-a75b-bcabe370f1e9-1 00:35:31.350 --> 00:35:35.002 built for these variables like what is what is a variable that ab561574-0e56-4e6d-a75b-bcabe370f1e9-2 00:35:35.002 --> 00:35:38.423 is more important to recovery agnostic to cost essentially ab561574-0e56-4e6d-a75b-bcabe370f1e9-3 00:35:38.423 --> 00:35:40.800 similar to like a lasso type assessment. 9ad5ec15-ee1c-49f8-9268-7e45f1d1a67e-0 00:35:41.560 --> 00:35:45.036 Then the next question would be, OK, how do we actually estimate 9ad5ec15-ee1c-49f8-9268-7e45f1d1a67e-1 00:35:45.036 --> 00:35:48.405 the median functional recovery time to evaluate whether or not 9ad5ec15-ee1c-49f8-9268-7e45f1d1a67e-2 00:35:48.405 --> 00:35:51.240 our check criteria of 30 days has actually been met? 1d161fc9-1a19-4e09-a932-ae0577684a4a-0 00:35:51.600 --> 00:35:54.964 So I mentioned to you that if we were to do this in today's 1d161fc9-1a19-4e09-a932-ae0577684a4a-1 00:35:54.964 --> 00:35:58.552 world, this would probably be a simulation based approach using 1d161fc9-1a19-4e09-a932-ae0577684a4a-2 00:35:58.552 --> 00:36:02.140 FEMA P58 and ATC138 for a high number of realizations to ensure 1d161fc9-1a19-4e09-a932-ae0577684a4a-3 00:36:02.140 --> 00:36:04.720 stability since this is a stochastic process. 3a489cb4-74c5-4181-a224-68462ffa3fa5-0 00:36:05.080 --> 00:36:07.661 And what we do is replace the entire thing with a surrogate 3a489cb4-74c5-4181-a224-68462ffa3fa5-1 00:36:07.661 --> 00:36:07.920 model. 9c1e0430-6bae-4ffd-8e28-418f4390947a-0 00:36:08.600 --> 00:36:11.357 Now when we get into surrogate models, there's a lot of people 9c1e0430-6bae-4ffd-8e28-418f4390947a-1 00:36:11.357 --> 00:36:13.984 in the community who are using them right now and there are 9c1e0430-6bae-4ffd-8e28-418f4390947a-2 00:36:13.984 --> 00:36:15.560 opinions on how you architect them. 7d5a4ae7-f1d4-4952-8200-614f8400a3a8-0 00:36:16.040 --> 00:36:17.160 I have a few views. 8c517660-390b-4b83-a282-d41ab005e2dc-0 00:36:17.720 --> 00:36:21.025 The first view is that a fully coupled architecture may not be 8c517660-390b-4b83-a282-d41ab005e2dc-1 00:36:21.025 --> 00:36:21.760 the best idea. b1e4390f-593d-4f47-9409-23bd895798bf-0 00:36:22.120 --> 00:36:24.561 So I'm showing you an architecture here where we can b1e4390f-593d-4f47-9409-23bd895798bf-1 00:36:24.561 --> 00:36:26.957 map different building enhancements directly to the b1e4390f-593d-4f47-9409-23bd895798bf-2 00:36:26.957 --> 00:36:27.280 answer. c102c63e-c878-477b-801d-497e4081ffb7-0 00:36:27.920 --> 00:36:31.374 The the disadvantage of this approach is it takes a long time c102c63e-c878-477b-801d-497e4081ffb7-1 00:36:31.374 --> 00:36:32.600 to train these models. 86c31b6f-8753-4fd7-b818-3016adae71ad-0 00:36:32.640 --> 00:36:34.080 It might take 3-4 days. 7893e434-94c0-4dc8-8c6d-f7e4867a6fc3-0 00:36:34.400 --> 00:36:37.856 And let's say, you know, Grace comes to me and says, oh, I want 7893e434-94c0-4dc8-8c6d-f7e4867a6fc3-1 00:36:37.856 --> 00:36:41.150 to, you know, I want to use this, this surrogate model for a 7893e434-94c0-4dc8-8c6d-f7e4867a6fc3-2 00:36:41.150 --> 00:36:44.120 case that's in Minnesota or, you know, somewhere else. b51df7cc-6982-430b-be88-0e1ec04e40d0-0 00:36:44.560 --> 00:36:47.003 And if we can't accommodate that in the architecture, now we have b51df7cc-6982-430b-be88-0e1ec04e40d0-1 00:36:47.003 --> 00:36:48.040 to retrain the entire thing. fd6665e7-58ea-4408-8e3a-77089a868d91-0 00:36:48.040 --> 00:36:50.720 And so it's not generalizable and it wastes resources. 648e3d35-839e-4809-b35c-0e9240737b08-0 00:36:51.240 --> 00:36:54.859 What I have proposed in this study is a version that totally 648e3d35-839e-4809-b35c-0e9240737b08-1 00:36:54.859 --> 00:36:58.598 decouples the engineering demand parameters or the engineering 648e3d35-839e-4809-b35c-0e9240737b08-2 00:36:58.598 --> 00:37:02.039 demand parameter prediction from the downtime assessment. 996f3275-40c8-4f95-96de-a2329866f7a0-0 00:37:02.040 --> 00:37:05.343 So for context, engineering demand parameters are these 996f3275-40c8-4f95-96de-a2329866f7a0-1 00:37:05.343 --> 00:37:08.587 variables in the FEMA P 58 assessment that account for 996f3275-40c8-4f95-96de-a2329866f7a0-2 00:37:08.587 --> 00:37:11.360 demands like storage drifts and accelerations. e5aa22a8-68c1-4d1c-a32d-d537ddf5ca13-0 00:37:11.720 --> 00:37:14.804 You can get a different vector of engineering demand parameters e5aa22a8-68c1-4d1c-a32d-d537ddf5ca13-1 00:37:14.804 --> 00:37:17.841 if you change the site, if you strengthen the building and can e5aa22a8-68c1-4d1c-a32d-d537ddf5ca13-2 00:37:17.841 --> 00:37:19.480 accommodate all of these changes. af8b550b-0c60-4b95-9a15-008276e65414-0 00:37:19.800 --> 00:37:22.692 And So what we did is we featurized them so that if say af8b550b-0c60-4b95-9a15-008276e65414-1 00:37:22.692 --> 00:37:25.482 tomorrow someone in this audience were to calibrate a af8b550b-0c60-4b95-9a15-008276e65414-2 00:37:25.482 --> 00:37:28.787 model for a different structural system or you know, maybe some af8b550b-0c60-4b95-9a15-008276e65414-3 00:37:28.787 --> 00:37:32.197 type of structural improvements, we can have that as an auxiliary af8b550b-0c60-4b95-9a15-008276e65414-4 00:37:32.197 --> 00:37:34.160 model that can be handled separately. 37f55628-7cf4-440b-bd1a-9258c5ce709e-0 00:37:34.480 --> 00:37:37.367 And then this model that we have calibrated here that includes 37f55628-7cf4-440b-bd1a-9258c5ce709e-1 00:37:37.367 --> 00:37:39.750 engineering demand parameters and in non structural 37f55628-7cf4-440b-bd1a-9258c5ce709e-2 00:37:39.750 --> 00:37:42.454 enhancements using those XI variables, I mentioned earlier 37f55628-7cf4-440b-bd1a-9258c5ce709e-3 00:37:42.454 --> 00:37:45.020 that these could be solely responsible for the downtime 37f55628-7cf4-440b-bd1a-9258c5ce709e-4 00:37:45.020 --> 00:37:45.799 assessment piece. a6412a3e-61d5-425e-a962-6ad4d615cc64-0 00:37:46.400 --> 00:37:49.235 And So what we did is we, we went ahead with this decoupled a6412a3e-61d5-425e-a962-6ad4d615cc64-1 00:37:49.235 --> 00:37:51.882 architecture and it worked really well in, in this case a6412a3e-61d5-425e-a962-6ad4d615cc64-2 00:37:51.882 --> 00:37:54.812 with a three story building, we have 3 variables or four that a6412a3e-61d5-425e-a962-6ad4d615cc64-3 00:37:54.812 --> 00:37:57.175 represent peak floor accelerations, including the a6412a3e-61d5-425e-a962-6ad4d615cc64-4 00:37:57.175 --> 00:37:59.680 ground or the roof, depending on how you look at it. 0beaaf62-5fbe-4960-a97b-623d050fa606-0 00:38:00.000 --> 00:38:02.680 Three story drift ratio variables. 7fcf25a9-2964-4b00-bdc8-a5e7fa16c902-0 00:38:03.080 --> 00:38:06.075 And then a series of 36 non structural improvement variables 7fcf25a9-2964-4b00-bdc8-a5e7fa16c902-1 00:38:06.075 --> 00:38:09.267 that account for things like did we improve the elevator, did we 7fcf25a9-2964-4b00-bdc8-a5e7fa16c902-2 00:38:09.267 --> 00:38:10.199 improve the stairs? 75d62bd7-a103-4cb3-a3be-05dd28e8b7ca-0 00:38:10.600 --> 00:38:13.819 And map all of that directly to the median functional recovery 75d62bd7-a103-4cb3-a3be-05dd28e8b7ca-1 00:38:13.819 --> 00:38:16.782 time since ultimately that is what's going to allow us to 75d62bd7-a103-4cb3-a3be-05dd28e8b7ca-2 00:38:16.782 --> 00:38:19.440 check whether or not we hit that target of 30 days. 3496c274-0d11-4c0d-82ee-fd6cc854a4cc-0 00:38:19.960 --> 00:38:23.029 And this achieved a very high predictive performance based on 3496c274-0d11-4c0d-82ee-fd6cc854a4cc-1 00:38:23.029 --> 00:38:23.920 the training data. a846f5a0-3e5d-4abf-b4ad-86d1663e219f-0 00:38:23.920 --> 00:38:26.572 We are definitely trying to overfit it in this case because a846f5a0-3e5d-4abf-b4ad-86d1663e219f-1 00:38:26.572 --> 00:38:28.120 this is an interpolation exercise. 6677b7b5-e4de-4beb-87ee-48d4b1d5b929-0 00:38:28.720 --> 00:38:30.880 So I came to you guys today with a demo. 5770129b-7cf1-483f-bf26-82e19e919ce8-0 00:38:30.880 --> 00:38:32.960 I'm going to show you how this actually works. b09fce43-b424-4cc4-8aaa-5e7226523912-0 00:38:33.160 --> 00:38:36.680 This is real time or pseudo real time, I don't know, but I think b09fce43-b424-4cc4-8aaa-5e7226523912-1 00:38:36.680 --> 00:38:39.280 you'll find that it's, it's interesting to see. 6cf2adbb-bcff-4409-a4fa-7349f12020ae-0 00:38:39.280 --> 00:38:43.141 So the algorithm is looking through, and this is a genetic 6cf2adbb-bcff-4409-a4fa-7349f12020ae-1 00:38:43.141 --> 00:38:46.806 algorithm, by the way, looking through the series of 36 6cf2adbb-bcff-4409-a4fa-7349f12020ae-2 00:38:46.806 --> 00:38:51.125 different components and it very quickly, I would say in a matter 6cf2adbb-bcff-4409-a4fa-7349f12020ae-3 00:38:51.125 --> 00:38:54.986 of seconds, sifted through the design space and identified 6cf2adbb-bcff-4409-a4fa-7349f12020ae-4 00:38:54.986 --> 00:38:58.847 12345 that are ultimately the best, I guess, components to 6cf2adbb-bcff-4409-a4fa-7349f12020ae-5 00:38:58.847 --> 00:39:02.905 actually change to achieve this 30 day target time to go from 6cf2adbb-bcff-4409-a4fa-7349f12020ae-6 00:39:02.905 --> 00:39:03.560 155 to 30. 9660b9af-0a9b-42bf-9a13-95018de13904-0 00:39:04.240 --> 00:39:06.360 And what's interesting is that this is agnostic of cost. e12d3ac6-08f0-48fe-bd92-30365bd85465-0 00:39:06.360 --> 00:39:09.657 These are the variables that have the highest influence on e12d3ac6-08f0-48fe-bd92-30365bd85465-1 00:39:09.657 --> 00:39:10.720 downtime reduction. 0735adcf-b409-47cf-855b-aeb7769bdb2b-0 00:39:11.560 --> 00:39:13.240 And so let's take a look at this a little bit more. be1cb5c6-da1a-457f-8d10-a088dd55f8dc-0 00:39:13.800 --> 00:39:16.920 So this is for a 30 day target. 54fa2c5a-80bf-415d-9d9b-ee556648b14b-0 00:39:17.280 --> 00:39:19.974 Now you can ask me, well, Omar, what if I wanted to repeat this 54fa2c5a-80bf-415d-9d9b-ee556648b14b-1 00:39:19.974 --> 00:39:22.543 for 20 days, 10 days, like I mean, like I might be exploring 54fa2c5a-80bf-415d-9d9b-ee556648b14b-2 00:39:22.543 --> 00:39:23.680 the design space right now. 97d77e64-9e5c-4b93-b9bc-b0db4086c4d5-0 00:39:24.240 --> 00:39:26.919 And I think that's where this approach really shines is that 97d77e64-9e5c-4b93-b9bc-b0db4086c4d5-1 00:39:26.919 --> 00:39:29.511 we can, if we for a specific check, if you're unsure about 97d77e64-9e5c-4b93-b9bc-b0db4086c4d5-2 00:39:29.511 --> 00:39:32.146 that 30 day marker, you want to, you want to tweak things a 97d77e64-9e5c-4b93-b9bc-b0db4086c4d5-3 00:39:32.146 --> 00:39:34.782 little bit, you can actually vary the target times, fix the 97d77e64-9e5c-4b93-b9bc-b0db4086c4d5-4 00:39:34.782 --> 00:39:36.320 seismic intensity and this repeat. a588de05-9345-4475-9e7b-d95e8b8d46bf-0 00:39:36.720 --> 00:39:39.791 And this entire graph took me maybe more, no more than maybe a588de05-9345-4475-9e7b-d95e8b8d46bf-1 00:39:39.791 --> 00:39:41.000 2-3 minutes to generate. 61e4dadc-b975-4642-bfd0-56484f7f02d8-0 00:39:41.320 --> 00:39:45.034 But it shows you as you get more ambitious with the functional 61e4dadc-b975-4642-bfd0-56484f7f02d8-1 00:39:45.034 --> 00:39:48.513 recovery time targets at this intensity, you can see which 61e4dadc-b975-4642-bfd0-56484f7f02d8-2 00:39:48.513 --> 00:39:50.400 components start to matter more. 352ac323-d19a-4948-bae7-a32049789141-0 00:39:50.720 --> 00:39:53.882 And if we're zooming in on this example, we can see that stairs 352ac323-d19a-4948-bae7-a32049789141-1 00:39:53.882 --> 00:39:56.847 for this very flexible steel building are important because 352ac323-d19a-4948-bae7-a32049789141-2 00:39:56.847 --> 00:39:59.811 stairs prevent if they are damaged, prevent egress, prevent 352ac323-d19a-4948-bae7-a32049789141-3 00:39:59.811 --> 00:40:02.480 the occupancy, therefore prevent functional recovery. 2875c5ec-9a62-47ad-93c8-a3e3a0541507-0 00:40:02.880 --> 00:40:05.658 You can also see the same with the glass curtain walls and the 2875c5ec-9a62-47ad-93c8-a3e3a0541507-1 00:40:05.658 --> 00:40:06.320 precast panels. f947adca-44ef-4dc3-8568-970201458b68-0 00:40:06.560 --> 00:40:09.722 A flexible building like this is all ultimately going to have f947adca-44ef-4dc3-8568-970201458b68-1 00:40:09.722 --> 00:40:10.080 drifts. 9ed21fde-dace-4bca-a32a-f9394fb95b2b-0 00:40:10.400 --> 00:40:13.411 And so those drifts are going to damage certain components that 9ed21fde-dace-4bca-a32a-f9394fb95b2b-1 00:40:13.411 --> 00:40:14.400 affect functionality. 7dd0c16b-d3a2-4d78-9fc8-d3cea543536f-0 00:40:14.720 --> 00:40:17.377 You can see that in more ambitious cases, things like the 7dd0c16b-d3a2-4d78-9fc8-d3cea543536f-1 00:40:17.377 --> 00:40:20.080 HVAC, things like the electric components start to matter. 559d5a30-8f1a-4c1a-848e-604e6a2985a0-0 00:40:20.480 --> 00:40:23.440 But the the idea here is, is that by using surrogate models, 559d5a30-8f1a-4c1a-848e-604e6a2985a0-1 00:40:23.440 --> 00:40:26.304 we can more efficiently scan the design space and start to 559d5a30-8f1a-4c1a-848e-604e6a2985a0-2 00:40:26.304 --> 00:40:28.440 develop some of that engineering intuition. cfa2489f-082b-4ff3-a001-b94ec6699938-0 00:40:29.000 --> 00:40:31.686 You could also come to me and say, oh, I like 30 days, but I cfa2489f-082b-4ff3-a001-b94ec6699938-1 00:40:31.686 --> 00:40:33.360 want to change the seismic intensity. 9e6d3762-2bd0-4041-8a67-f14bb2dc221f-0 00:40:33.560 --> 00:40:37.189 We can do the same exact thing, repeat the analysis and then 9e6d3762-2bd0-4041-8a67-f14bb2dc221f-1 00:40:37.189 --> 00:40:40.760 parse out for a 30 day target across different intensities. c6413d1a-dc70-4685-a868-8bef77e41e7a-0 00:40:41.000 --> 00:40:42.640 What would be those changes we need to make? b71f63d3-5f40-4384-83af-ea9bcbb2ab79-0 00:40:42.880 --> 00:40:45.513 And if you're, if, if any of you are asking me what do the b71f63d3-5f40-4384-83af-ea9bcbb2ab79-1 00:40:45.513 --> 00:40:47.880 numbers mean, I apologize if I explained it earlier. 3f0109f3-54fb-4775-89cc-e386dca76c8a-0 00:40:48.080 --> 00:40:50.360 A1 means we do nothing to that component. 36f644c1-cb67-456c-8c6a-73a788b448cf-0 00:40:50.880 --> 00:40:54.661 A2 A 1.5, A 3 is basically saying for every quantity of 36f644c1-cb67-456c-8c6a-73a788b448cf-1 00:40:54.661 --> 00:40:58.511 those components in the building, we are 1.5 exiting the 36f644c1-cb67-456c-8c6a-73a788b448cf-2 00:40:58.511 --> 00:41:01.280 medium capacity of of all damage states. 2e3fbbde-eab0-4db4-b349-b46dd2dadfee-0 00:41:01.280 --> 00:41:02.240 That's basically what it means. 86af7269-df30-47d2-8390-a65597ffacd9-0 00:41:03.960 --> 00:41:05.200 OK, so this is all great. 0faf46cf-1600-4f39-9f7a-ab5642e7414a-0 00:41:05.200 --> 00:41:08.718 We have some insights here one of the things that I, I think is 0faf46cf-1600-4f39-9f7a-ab5642e7414a-1 00:41:08.718 --> 00:41:11.961 interesting is that we can also unveil the influence of of 0faf46cf-1600-4f39-9f7a-ab5642e7414a-2 00:41:11.961 --> 00:41:14.875 different structural interventions on an optimal non 0faf46cf-1600-4f39-9f7a-ab5642e7414a-3 00:41:14.875 --> 00:41:16.360 structural design solution. a925019a-b153-4ed6-b438-b8f580804998-0 00:41:16.360 --> 00:41:19.321 What I mean by that is is like let's see how this optimal a925019a-b153-4ed6-b438-b8f580804998-1 00:41:19.321 --> 00:41:22.384 solution changes if we did stiffen the building and I think a925019a-b153-4ed6-b438-b8f580804998-2 00:41:22.384 --> 00:41:25.294 this is interesting because I told you guys earlier that a925019a-b153-4ed6-b438-b8f580804998-3 00:41:25.294 --> 00:41:28.255 sometimes stiffening the building can be to the detriment a925019a-b153-4ed6-b438-b8f580804998-4 00:41:28.255 --> 00:41:30.399 of of non structural component hardening. 8258a294-eed1-43b0-a3d4-64136c54496f-0 00:41:30.800 --> 00:41:33.795 So let's go ahead and, and vary the target times and fix the 8258a294-eed1-43b0-a3d4-64136c54496f-1 00:41:33.795 --> 00:41:34.680 seismic intensity. 315caead-13af-4198-b57c-c88f454028ab-0 00:41:35.160 --> 00:41:38.485 And let's go and actually change, Let's have 3 versions of 315caead-13af-4198-b57c-c88f454028ab-1 00:41:38.485 --> 00:41:41.641 this building, 1 version where the structural system is 315caead-13af-4198-b57c-c88f454028ab-2 00:41:41.641 --> 00:41:45.136 identical, 1 version where we increase the importance factor, 315caead-13af-4198-b57c-c88f454028ab-3 00:41:45.136 --> 00:41:47.560 IE we make it stiffer and stronger to 1.5. 3b3896d8-e3b1-4456-ae35-1c9739252f50-0 00:41:47.880 --> 00:41:50.738 And then this crazy, I would say not so realistic importance 3b3896d8-e3b1-4456-ae35-1c9739252f50-1 00:41:50.738 --> 00:41:51.160 factor 2. 353bdddc-8718-41a9-8f78-2c16fec0f64c-0 00:41:51.160 --> 00:41:53.480 When we go all the way, we're going to go strengthen this 353bdddc-8718-41a9-8f78-2c16fec0f64c-1 00:41:53.480 --> 00:41:54.840 thing to the to the limit, right? 98698447-e369-4f30-99fa-0638de434fc2-0 00:41:56.000 --> 00:42:00.560 What we can do then is map the optimal F of X. 1176116f-1327-493c-b4da-7d3ef9b27769-0 00:42:00.560 --> 00:42:05.056 This is a pre abstract metric, but you can think of it as the 1176116f-1327-493c-b4da-7d3ef9b27769-1 00:42:05.056 --> 00:42:08.320 average XI, the average improvement we have. 9f0a4600-86b7-46bb-bf11-e5c9fe49b94f-0 00:42:08.560 --> 00:42:13.159 We, we, we have, we have or the optimal average XI shift for 9f0a4600-86b7-46bb-bf11-e5c9fe49b94f-1 00:42:13.159 --> 00:42:15.120 that specific target time. 68ab49af-760c-4d2a-929b-088345af45d5-0 00:42:15.120 --> 00:42:18.579 So you can see here average shift is one because we're 68ab49af-760c-4d2a-929b-088345af45d5-1 00:42:18.579 --> 00:42:22.478 already there like the baseline case is already achieving 100 68ab49af-760c-4d2a-929b-088345af45d5-2 00:42:22.478 --> 00:42:25.120 and 55155 days of functional public time. 5cea5cc5-88cb-4eec-9587-529e19ffdefb-0 00:42:25.520 --> 00:42:28.633 It's as you go further that you start to see, OK, this average 5cea5cc5-88cb-4eec-9587-529e19ffdefb-1 00:42:28.633 --> 00:42:31.698 shift is increasing because we need to make some improvements 5cea5cc5-88cb-4eec-9587-529e19ffdefb-2 00:42:31.698 --> 00:42:33.280 to the building to to get there. 19df76f6-6a78-4be1-a963-a53901173376-0 00:42:33.280 --> 00:42:36.278 And I'll paint this more tangibly by showing you the 19df76f6-6a78-4be1-a963-a53901173376-1 00:42:36.278 --> 00:42:37.240 optimal solution. ece1c2c0-d12a-415a-8ffd-3fff12649389-0 00:42:37.480 --> 00:42:39.880 For an example case, let's look at 120 days. 8e6865be-829f-4ef7-b422-1af93141ea66-0 00:42:39.880 --> 00:42:43.935 So we started right quote conforming 155 days, pulling now 8e6865be-829f-4ef7-b422-1af93141ea66-1 00:42:43.935 --> 00:42:44.760 to 120 days. a41f71b4-da94-4980-b463-610f06bb1d6b-0 00:42:45.040 --> 00:42:47.840 What is the solution if we did nothing in the building? caabe9b5-7908-418a-b4eb-3851a3ad216a-0 00:42:47.840 --> 00:42:49.520 Strengthen it a little bit, strengthen it a lot. dc0f953f-5301-4409-836f-72cacc057f9b-0 00:42:50.120 --> 00:42:54.562 You can see that when the target was very close to the original, dc0f953f-5301-4409-836f-72cacc057f9b-1 00:42:54.562 --> 00:42:58.389 these structurally improved versions, you know, they're dc0f953f-5301-4409-836f-72cacc057f9b-2 00:42:58.389 --> 00:43:00.440 already kind of getting there. 567449cf-e87e-45a5-a807-d2d173b4e7c1-0 00:43:00.440 --> 00:43:04.510 They've already they're already achieving 120 days without any 567449cf-e87e-45a5-a807-d2d173b4e7c1-1 00:43:04.510 --> 00:43:06.320 non structural intervention. 74937264-3310-4968-87f4-4da08952178e-0 00:43:06.680 --> 00:43:09.539 And maybe this case where we have a no structural 74937264-3310-4968-87f4-4da08952178e-1 00:43:09.539 --> 00:43:13.141 improvements will make a couple of improvements or upgrades to 74937264-3310-4968-87f4-4da08952178e-2 00:43:13.141 --> 00:43:14.800 the facade and the staircase. 898dd0d5-9dda-4021-9780-3d0bee63e344-0 00:43:15.560 --> 00:43:20.720 But let's go in and push it to the limit to explore 21 days. 7ca36ebe-7590-4153-9f69-5d4c624d998d-0 00:43:21.000 --> 00:43:24.481 What I think is interesting about this case is that the 7ca36ebe-7590-4153-9f69-5d4c624d998d-1 00:43:24.481 --> 00:43:28.459 trend actually reverses because at this point if we look at say 7ca36ebe-7590-4153-9f69-5d4c624d998d-2 00:43:28.459 --> 00:43:31.816 the building that had no structural improvements, the 7ca36ebe-7590-4153-9f69-5d4c624d998d-3 00:43:31.816 --> 00:43:35.359 average XI or the optimal solution is actually the best. 9c8c932a-f2c3-4c0b-b06b-9a62d1936ee6-0 00:43:35.840 --> 00:43:39.054 Because here there are no significant acceleration 9c8c932a-f2c3-4c0b-b06b-9a62d1936ee6-1 00:43:39.054 --> 00:43:42.457 amplifications that would require us to significantly 9c8c932a-f2c3-4c0b-b06b-9a62d1936ee6-2 00:43:42.457 --> 00:43:44.600 improve non structural down here. fe7191ca-77af-4623-be7a-fbf4a92f8222-0 00:43:45.000 --> 00:43:48.195 Whereas with the sniffing buildings, we have to make more fe7191ca-77af-4623-be7a-fbf4a92f8222-1 00:43:48.195 --> 00:43:50.840 extensive non structural upgrades on this side. e5f71a95-a32e-4130-b43d-f44640566441-0 00:43:51.480 --> 00:43:53.995 I've seen this plot many times in my life, so I have a mental e5f71a95-a32e-4130-b43d-f44640566441-1 00:43:53.995 --> 00:43:54.320 mapping. f2d5161e-0ba6-489c-8f63-34d8c6e58724-0 00:43:54.560 --> 00:43:58.930 But you can generally imagine that the that the top components f2d5161e-0ba6-489c-8f63-34d8c6e58724-1 00:43:58.930 --> 00:44:02.746 like the panels, curtain walls, gypsum are story drift f2d5161e-0ba6-489c-8f63-34d8c6e58724-2 00:44:02.746 --> 00:44:03.440 sensitive. a3838cb7-2001-4d96-bde6-9df75f347864-0 00:44:03.880 --> 00:44:06.800 And then these ones here are more acceleration sensitive. 285a90b2-8e23-49e0-96bf-4d7dfab33e91-0 00:44:07.240 --> 00:44:11.148 And so you can see that for these very stiffened buildings 285a90b2-8e23-49e0-96bf-4d7dfab33e91-1 00:44:11.148 --> 00:44:15.123 that have higher accelerations, more extensive upgrades are 285a90b2-8e23-49e0-96bf-4d7dfab33e91-2 00:44:15.123 --> 00:44:19.296 required for these acceleration sensitive components to get to 285a90b2-8e23-49e0-96bf-4d7dfab33e91-3 00:44:19.296 --> 00:44:23.072 21 days, whereas the original structural system required 285a90b2-8e23-49e0-96bf-4d7dfab33e91-4 00:44:23.072 --> 00:44:24.000 slightly less. 0ccb2802-d923-4e33-9309-eeed8580501e-0 00:44:24.040 --> 00:44:28.132 And of course, this average XI metric is, you know, it's, it's 0ccb2802-d923-4e33-9309-eeed8580501e-1 00:44:28.132 --> 00:44:32.095 just a way of kind of giving us a sense of or a benchmark to 0ccb2802-d923-4e33-9309-eeed8580501e-2 00:44:32.095 --> 00:44:32.680 optimize. a38b7323-b0d4-4088-a6ee-a1afcafd59cd-0 00:44:32.680 --> 00:44:35.971 But I think regardless the, these, these results are a38b7323-b0d4-4088-a6ee-a1afcafd59cd-1 00:44:35.971 --> 00:44:39.884 insightful because it can tell us maybe, maybe we we should be a38b7323-b0d4-4088-a6ee-a1afcafd59cd-2 00:44:39.884 --> 00:44:43.610 thinking about interventions differently depending on where a38b7323-b0d4-4088-a6ee-a1afcafd59cd-3 00:44:43.610 --> 00:44:44.480 our target is. 317a2df5-0c88-40e3-82f5-c064f9fa907b-0 00:44:44.480 --> 00:44:46.040 I think that's really the take away here. 63f4b539-e1cc-410b-9fb5-7ed92be538d8-0 00:44:46.840 --> 00:44:49.791 And so in this research we talked a little bit about this 63f4b539-e1cc-410b-9fb5-7ed92be538d8-1 00:44:49.791 --> 00:44:52.844 optimization framework, which is really apoc applied to one 63f4b539-e1cc-410b-9fb5-7ed92be538d8-2 00:44:52.844 --> 00:44:56.000 building, but can be generically applied to many other cases. 2f00eeba-469c-4fd7-9b8a-6e299104564b-0 00:44:56.400 --> 00:44:59.336 I presented a neural network architecture that I believe is 2f00eeba-469c-4fd7-9b8a-6e299104564b-1 00:44:59.336 --> 00:45:02.125 is very well suited for a problem like this and then how 2f00eeba-469c-4fd7-9b8a-6e299104564b-2 00:45:02.125 --> 00:45:05.208 the framework can be deployed for a code conforming case study 2f00eeba-469c-4fd7-9b8a-6e299104564b-3 00:45:05.208 --> 00:45:05.600 example. c684a1e0-c84b-4df4-b03a-d9e4bc4dafab-0 00:45:05.840 --> 00:45:08.840 You could also do this for an existing building for retrofits. 3f09cb88-c099-4f59-9e0f-eff8f69ff5fa-0 00:45:09.120 --> 00:45:11.760 This type of framework can be applied to many different cases. c21e75f4-5d9b-4e58-827a-41bef916aa6c-0 00:45:12.400 --> 00:45:15.341 So today we talked about, I would say a fruit salad here, c21e75f4-5d9b-4e58-827a-41bef916aa6c-1 00:45:15.341 --> 00:45:17.320 but we really started with objectives. 2a661150-2242-4e53-826c-8606f44f495d-0 00:45:17.840 --> 00:45:20.978 We talked about how performance objectives are a goal plus a 2a661150-2242-4e53-826c-8606f44f495d-1 00:45:20.978 --> 00:45:23.910 checking procedure, How goal metrics are not necessarily 2a661150-2242-4e53-826c-8606f44f495d-2 00:45:23.910 --> 00:45:27.100 correlated and how using a check that relies on a conditional 2a661150-2242-4e53-826c-8606f44f495d-3 00:45:27.100 --> 00:45:30.392 probability of failure between 10 and 20% significantly and can 2a661150-2242-4e53-826c-8606f44f495d-4 00:45:30.392 --> 00:45:33.479 reliably increase confidence that we're getting to our goal 2a661150-2242-4e53-826c-8606f44f495d-5 00:45:33.479 --> 00:45:36.360 if we're going to only check the fragility in one spot. 83b9b6a8-58dd-45ab-935c-10e0e8eb2909-0 00:45:37.040 --> 00:45:39.719 The second part of this research I showed you how a machine 83b9b6a8-58dd-45ab-935c-10e0e8eb2909-1 00:45:39.719 --> 00:45:42.309 learning based optimization framework that can be used to 83b9b6a8-58dd-45ab-935c-10e0e8eb2909-2 00:45:42.309 --> 00:45:45.123 rapidly extract those strategies based on the design check and 83b9b6a8-58dd-45ab-935c-10e0e8eb2909-3 00:45:45.123 --> 00:45:47.713 how we can calibrate the surrogate model architectures to 83b9b6a8-58dd-45ab-935c-10e0e8eb2909-4 00:45:47.713 --> 00:45:48.160 get there. 4a073340-3588-4c2c-92a6-7dff17c314d7-0 00:45:49.080 --> 00:45:52.338 But I think in terms of the research I mentioned you guys, I 4a073340-3588-4c2c-92a6-7dff17c314d7-1 00:45:52.338 --> 00:45:55.490 came to Stanford because I wanted to understand how can we 4a073340-3588-4c2c-92a6-7dff17c314d7-2 00:45:55.490 --> 00:45:57.200 design buildings for resilience. 464c9273-4736-4c6c-866e-0ae4c871c221-0 00:45:57.200 --> 00:46:00.028 And I think that these approaches are extremely 464c9273-4736-4c6c-866e-0ae4c871c221-1 00:46:00.028 --> 00:46:01.560 promising to get us there. 5092516d-01fe-4b00-a4b2-ecce4765f7e4-0 00:46:01.920 --> 00:46:05.881 But in terms of where they fit in the, in the grand scheme of 5092516d-01fe-4b00-a4b2-ecce4765f7e4-1 00:46:05.881 --> 00:46:10.098 the built world today, there are these different players that are 5092516d-01fe-4b00-a4b2-ecce4765f7e4-2 00:46:10.098 --> 00:46:13.421 influencing our built environment and how a a given 5092516d-01fe-4b00-a4b2-ecce4765f7e4-3 00:46:13.421 --> 00:46:17.000 building may influence a community recovery trajectory. 9094e8d2-b231-4891-a2be-37518544ab7e-0 00:46:17.480 --> 00:46:20.722 A tool like this, research like this can really help engineers 9094e8d2-b231-4891-a2be-37518544ab7e-1 00:46:20.722 --> 00:46:23.707 who are doing this bottoms up advocacy, who are designing 9094e8d2-b231-4891-a2be-37518544ab7e-2 00:46:23.707 --> 00:46:26.897 these case study examples and in government who are trying to 9094e8d2-b231-4891-a2be-37518544ab7e-3 00:46:26.897 --> 00:46:30.088 understand how do we flex our provisions to get us to a point 9094e8d2-b231-4891-a2be-37518544ab7e-4 00:46:30.088 --> 00:46:32.816 where we're considering functional recovery, which I 9094e8d2-b231-4891-a2be-37518544ab7e-5 00:46:32.816 --> 00:46:33.999 think is very exciting. f4484332-8262-4ff8-8bb3-3e9e5c006853-0 00:46:34.280 --> 00:46:37.165 And if we do this for enough buildings, we can successfully f4484332-8262-4ff8-8bb3-3e9e5c006853-1 00:46:37.165 --> 00:46:39.907 support tenants who are within these different community f4484332-8262-4ff8-8bb3-3e9e5c006853-2 00:46:39.907 --> 00:46:42.360 functions and create a more resilient built world. 38d16ea5-be54-4dd7-9720-1391beda61f3-0 00:46:43.200 --> 00:46:46.740 But there is a caveat here, and that is one thing that has 38d16ea5-be54-4dd7-9720-1391beda61f3-1 00:46:46.740 --> 00:46:50.460 shifted my attention at least in recent months, that a lot of 38d16ea5-be54-4dd7-9720-1391beda61f3-2 00:46:50.460 --> 00:46:52.800 this work exists in the realm of risk. eb56c1f1-e013-40bd-b118-2051634369ee-0 00:46:53.240 --> 00:46:57.443 And these risk models are very powerful and require a lot of eb56c1f1-e013-40bd-b118-2051634369ee-1 00:46:57.443 --> 00:47:00.200 data and are necessary to this problem. 10fddd7a-8bbb-4f35-8c27-f24d67a0499f-0 00:47:00.640 --> 00:47:03.688 But what I have seen in industry is that a lot of the 10fddd7a-8bbb-4f35-8c27-f24d67a0499f-1 00:47:03.688 --> 00:47:07.301 stakeholders I have spoken to do not feel confident about their 10fddd7a-8bbb-4f35-8c27-f24d67a0499f-2 00:47:07.301 --> 00:47:08.599 inputs to these models. c32b7928-59d1-41cb-b7e8-0b63402dd194-0 00:47:08.800 --> 00:47:12.141 They don't feel confident about various data points on exposure c32b7928-59d1-41cb-b7e8-0b63402dd194-1 00:47:12.141 --> 00:47:15.379 that are required to give us an accurate understanding of our c32b7928-59d1-41cb-b7e8-0b63402dd194-2 00:47:15.379 --> 00:47:18.564 portfolios and our building stock that would serve as inputs c32b7928-59d1-41cb-b7e8-0b63402dd194-3 00:47:18.564 --> 00:47:19.400 to these models. d31c2d8e-f906-4f94-90de-c7044b86bbfe-0 00:47:19.800 --> 00:47:23.589 And so in the next chapter of my life, I have dedicated it to, as d31c2d8e-f906-4f94-90de-c7044b86bbfe-1 00:47:23.589 --> 00:47:26.977 Grace mentioned, starting a company that is solely focused d31c2d8e-f906-4f94-90de-c7044b86bbfe-2 00:47:26.977 --> 00:47:30.250 on addressing this issue using AI that's been trained on d31c2d8e-f906-4f94-90de-c7044b86bbfe-3 00:47:30.250 --> 00:47:33.581 structural engineering domain knowledge and trying to, at d31c2d8e-f906-4f94-90de-c7044b86bbfe-4 00:47:33.581 --> 00:47:37.255 scale, try to discern how can we uncover the maybe the top 1015 d31c2d8e-f906-4f94-90de-c7044b86bbfe-5 00:47:37.255 --> 00:47:40.988 features that influence risk to build the exposure data layer to d31c2d8e-f906-4f94-90de-c7044b86bbfe-6 00:47:40.988 --> 00:47:43.399 power the next generation of risk models. cabb3e86-8db3-4dff-8364-6fa4539eb492-0 00:47:43.720 --> 00:47:45.280 That is really what I'm focused on today. f6f3e7e7-6020-4679-b3ce-9aea84f05c22-0 00:47:45.280 --> 00:47:47.880 I spend lots of time sleepless nights thinking about it. bf89d552-8cd7-4d43-ab9c-7237bad10c32-0 00:47:48.200 --> 00:47:51.212 And the goal would be to interface with people in the bf89d552-8cd7-4d43-ab9c-7237bad10c32-1 00:47:51.212 --> 00:47:54.504 private sector, but also the public sector and academia to bf89d552-8cd7-4d43-ab9c-7237bad10c32-2 00:47:54.504 --> 00:47:56.959 support research that requires better data. d8235b4b-1579-494a-940d-fd4984538a72-0 00:47:57.360 --> 00:47:59.160 And we're already starting to work with folks. e010c4fb-8fe3-400f-84f1-ded7c3fc5505-0 00:47:59.400 --> 00:48:02.618 And my invitation to everyone watching this today is that if e010c4fb-8fe3-400f-84f1-ded7c3fc5505-1 00:48:02.618 --> 00:48:05.732 this type of data, high fidelity and credible, can support e010c4fb-8fe3-400f-84f1-ded7c3fc5505-2 00:48:05.732 --> 00:48:09.109 resilience research right now, please let me know because we're e010c4fb-8fe3-400f-84f1-ded7c3fc5505-3 00:48:09.109 --> 00:48:10.639 very interested in a partner. 81a70a53-0aef-4246-bf22-67b931cbebdf-0 00:48:11.000 --> 00:48:13.886 And of course, as you guys know about me, I'm an optimist and I 81a70a53-0aef-4246-bf22-67b931cbebdf-1 00:48:13.886 --> 00:48:15.600 believe that the future is resilient. 6adbc841-956f-488c-98c0-6e0454aef293-0 00:48:15.880 --> 00:48:17.240 Thank you very much for tuning in today. 98fe7f46-1a30-46d3-9654-05f0b0e39cb0-0 00:48:23.990 --> 00:48:26.070 You any questions in the room? 44641b84-5ec8-44df-b437-a3ecdf8f7175-0 00:48:29.920 --> 00:48:32.868 Oh, yes, please, Steve, great talk and I really like the way 44641b84-5ec8-44df-b437-a3ecdf8f7175-1 00:48:32.868 --> 00:48:35.720 you sort of decouple all these really complicated systems. 9204da11-e9ad-4cba-9b00-29d62eca9498-0 00:48:36.080 --> 00:48:39.568 So and I gather from your final comment, one of the problems is 9204da11-e9ad-4cba-9b00-29d62eca9498-1 00:48:39.568 --> 00:48:43.003 how do you train these machine learning algorithms to actually 9204da11-e9ad-4cba-9b00-29d62eca9498-2 00:48:43.003 --> 00:48:46.328 understand the controls for a particular kind of building on 9204da11-e9ad-4cba-9b00-29d62eca9498-3 00:48:46.328 --> 00:48:48.999 functional recovery like a hospital for exactly. 1950770d-a97a-4904-9814-33968394695d-0 00:48:49.600 --> 00:48:51.520 So there's a lot of expert knowledge embedded. d9d6c3a4-2c02-4f0f-9b40-d9dc81fdc98d-0 00:48:51.680 --> 00:48:54.698 How does HVAC versus electrical versus stairways, all these d9d6c3a4-2c02-4f0f-9b40-d9dc81fdc98d-1 00:48:54.698 --> 00:48:56.560 things, how does it impact coverage? 6f8e5850-ab3b-4fba-b968-8b6aa44c5c91-0 00:48:56.960 --> 00:48:59.480 Is that based on observations after earthquakes? ff29174d-4b19-452c-93c0-c85b047ff512-0 00:48:59.600 --> 00:49:00.600 How do you determine them? ba8247a0-682d-4226-831b-f1643f0227ad-0 00:49:00.920 --> 00:49:02.000 No, this is a great question. 792ec01d-3331-46ae-8518-bdec0fac18ad-0 00:49:02.080 --> 00:49:06.595 And I think this if we go back to some of these points I 792ec01d-3331-46ae-8518-bdec0fac18ad-1 00:49:06.595 --> 00:49:10.160 mentioned on how the models are are trained. fe49609a-2951-440e-acb5-60f7f179ecf4-0 00:49:10.520 --> 00:49:14.785 So the models today are learning from simulations and these fe49609a-2951-440e-acb5-60f7f179ecf4-1 00:49:14.785 --> 00:49:19.050 simulations, which are coming from FEMA P58 and ATC138, are fe49609a-2951-440e-acb5-60f7f179ecf4-2 00:49:19.050 --> 00:49:23.102 attempting to embed at the component level some of these fe49609a-2951-440e-acb5-60f7f179ecf4-3 00:49:23.102 --> 00:49:23.600 things. fa57c8d8-6673-41ce-a7c8-e996ffd32f6b-0 00:49:23.920 --> 00:49:27.848 For example, with ATC 138 that is more focused on the downtime fa57c8d8-6673-41ce-a7c8-e996ffd32f6b-1 00:49:27.848 --> 00:49:28.160 side. e2dd0ff6-fdbb-4114-9c03-9058cc4637f0-0 00:49:28.160 --> 00:49:31.297 I know for a fact that the impeding factors themselves have e2dd0ff6-fdbb-4114-9c03-9058cc4637f0-1 00:49:31.297 --> 00:49:34.592 been calibrated on past events and those come from our limited e2dd0ff6-fdbb-4114-9c03-9058cc4637f0-2 00:49:34.592 --> 00:49:37.886 sources of people actually going out collecting these impeding e2dd0ff6-fdbb-4114-9c03-9058cc4637f0-3 00:49:37.886 --> 00:49:38.880 factor data points. 1d8f956b-b062-4253-86ac-26fd597a30ff-0 00:49:39.280 --> 00:49:42.934 Unfortunately though, I feel like a lot of that data isn't 1d8f956b-b062-4253-86ac-26fd597a30ff-1 00:49:42.934 --> 00:49:46.774 tethered to a specific or is not, is not categorized in terms 1d8f956b-b062-4253-86ac-26fd597a30ff-2 00:49:46.774 --> 00:49:50.677 of occupancy type many of the times or maybe it's like focused 1d8f956b-b062-4253-86ac-26fd597a30ff-3 00:49:50.677 --> 00:49:52.039 on one occupancy type. a2a6306d-1fd2-4dd4-a4b1-560d45ece780-0 00:49:52.040 --> 00:49:55.055 Maybe it's focused on housing, not so much, you know, looking a2a6306d-1fd2-4dd4-a4b1-560d45ece780-1 00:49:55.055 --> 00:49:56.320 at hospitals specifically. d12ecaa8-581e-470b-9f48-1b9fcc29e3de-0 00:49:56.720 --> 00:50:00.643 I think that one of the the things that that this model does d12ecaa8-581e-470b-9f48-1b9fcc29e3de-1 00:50:00.643 --> 00:50:04.439 well is it's basically like whatever we do to improve FEMA d12ecaa8-581e-470b-9f48-1b9fcc29e3de-2 00:50:04.439 --> 00:50:07.720 P58 and ATC138IS reflected in the surrogate model. 75fee107-606d-4f52-9244-b44a63000c46-0 00:50:08.360 --> 00:50:11.762 But I'd say right now the 20 years of research that we put 75fee107-606d-4f52-9244-b44a63000c46-1 00:50:11.762 --> 00:50:15.221 into FEMA P 58 as a method are there, but there is a lot of 75fee107-606d-4f52-9244-b44a63000c46-2 00:50:15.221 --> 00:50:17.240 work to do on specific components. 7785c9c8-0c75-4eac-ad6b-80e545b6eff0-0 00:50:17.600 --> 00:50:20.800 The FEMA P58 database only has 700 components. 8e744bd3-1ac6-4d58-98f3-8d997baa094e-0 00:50:21.040 --> 00:50:24.006 That's not nearly enough to represent the vast variety of 8e744bd3-1ac6-4d58-98f3-8d997baa094e-1 00:50:24.006 --> 00:50:27.280 seismically certified equipment that exists in these hospitals. 5b297473-e8b2-4c36-8107-c56bd3d2d9d1-0 00:50:27.440 --> 00:50:31.171 And one of the limitations I've seen is in this, in this demo I 5b297473-e8b2-4c36-8107-c56bd3d2d9d1-1 00:50:31.171 --> 00:50:34.320 showed you guys one of those numbers ever exceeded 3. b8e7014c-6c42-4c8f-a733-e86154dade07-0 00:50:34.640 --> 00:50:37.748 That's because I artificially capped the constraint on the b8e7014c-6c42-4c8f-a733-e86154dade07-1 00:50:37.748 --> 00:50:40.857 improvement at 3 based on my knowledge and what the trends b8e7014c-6c42-4c8f-a733-e86154dade07-2 00:50:40.857 --> 00:50:42.280 I've seen in this database. f80505ee-2c51-430f-9288-4042eef7e9a5-0 00:50:42.480 --> 00:50:45.598 But there could be a scenario where seismically certified f80505ee-2c51-430f-9288-4042eef7e9a5-1 00:50:45.598 --> 00:50:48.823 equipment for certain, for certain hospitals or, or certain f80505ee-2c51-430f-9288-4042eef7e9a5-2 00:50:48.823 --> 00:50:51.834 types of very important equipment could be 10XI mean it f80505ee-2c51-430f-9288-4042eef7e9a5-3 00:50:51.834 --> 00:50:54.200 could be 11X if it's seismically certified. f0bf0f95-6f94-48c7-918d-376d3459d587-0 00:50:54.200 --> 00:50:55.280 And that's not reflected here. 509289fe-d65c-4e07-b01d-e07451e6554c-0 00:50:55.560 --> 00:50:58.143 So I think one of the things that I wrote in my memo as I 509289fe-d65c-4e07-b01d-e07451e6554c-1 00:50:58.143 --> 00:50:59.880 departed Stanford, they make us right. b8826f63-f685-4519-bb80-c4b79c2da06f-0 00:50:59.880 --> 00:51:02.720 Basically, what do we leave for the next students who come in? a6c8e88d-d998-4f2c-a00a-d46da9504396-0 00:51:02.720 --> 00:51:05.285 I was like, please take a look at all this seismically a6c8e88d-d998-4f2c-a00a-d46da9504396-1 00:51:05.285 --> 00:51:08.269 simplified equipment and get us better data on both the cost of a6c8e88d-d998-4f2c-a00a-d46da9504396-2 00:51:08.269 --> 00:51:11.254 improvement, then it also all of the other fragilities that are a6c8e88d-d998-4f2c-a00a-d46da9504396-3 00:51:11.254 --> 00:51:13.120 out there that we're not incorporating. 438bab47-d5f2-4671-a4e6-6d7ac436ead3-0 00:51:13.440 --> 00:51:17.413 The other thing is that you'll notice that I never, I, I didn't 438bab47-d5f2-4671-a4e6-6d7ac436ead3-1 00:51:17.413 --> 00:51:19.400 make this a discretized problem. 2ef774e6-fc62-47bc-b4ea-a8e60ac1e3c7-0 00:51:19.600 --> 00:51:22.232 So I never said, oh, are we choosing component A or 2ef774e6-fc62-47bc-b4ea-a8e60ac1e3c7-1 00:51:22.232 --> 00:51:22.840 component B? 53607911-1dd3-4b59-8d77-f2503b260e70-0 00:51:23.080 --> 00:51:26.013 That is because the I do not believe that the FEMA P58 53607911-1dd3-4b59-8d77-f2503b260e70-1 00:51:26.013 --> 00:51:29.160 database represents all of the scenarios that exist today. 1941dc8b-8f5e-4024-be96-c9d84de9d048-0 00:51:29.640 --> 00:51:32.972 And actually I would rather this algorithm tell me the fragility 1941dc8b-8f5e-4024-be96-c9d84de9d048-1 00:51:32.972 --> 00:51:35.895 I need to create to make that target happen than have to 1941dc8b-8f5e-4024-be96-c9d84de9d048-2 00:51:35.895 --> 00:51:38.818 choose from say 3 or 4 options of HVAC that exist in the 1941dc8b-8f5e-4024-be96-c9d84de9d048-3 00:51:38.818 --> 00:51:39.280 database. 232000a2-8cbf-49f6-85b9-d0bb043fd1d4-0 00:51:39.520 --> 00:51:41.843 There are some very passionate and great people working on 232000a2-8cbf-49f6-85b9-d0bb043fd1d4-1 00:51:41.843 --> 00:51:42.040 this. 5e9666aa-a650-4287-9a4f-41301f31c47d-0 00:51:42.040 --> 00:51:44.851 I know people at SP3 are looking at fragilities all the time and 5e9666aa-a650-4287-9a4f-41301f31c47d-1 00:51:44.851 --> 00:51:47.447 they have partnerships with manufacturers right now looking 5e9666aa-a650-4287-9a4f-41301f31c47d-2 00:51:47.447 --> 00:51:47.880 into this. 7b27390c-f36c-4af3-8a03-f97fb2b32168-0 00:51:48.280 --> 00:51:51.176 But I think one of the it's not necessarily related, but one of 7b27390c-f36c-4af3-8a03-f97fb2b32168-1 00:51:51.176 --> 00:51:53.440 the things that is still a major gap is the cost. 03a63709-5144-4d2d-9d5e-e76350423afc-0 00:51:53.840 --> 00:51:56.882 Like we still don't have a good handle on how cost functions map 03a63709-5144-4d2d-9d5e-e76350423afc-1 00:51:56.882 --> 00:51:58.240 to any of these improvements. 6295baec-da38-4716-b3a9-082869738878-0 00:52:00.120 --> 00:52:01.280 Yeah, of course that's great. 1f21be2a-be66-4012-9a20-d358620b14a9-0 00:52:03.480 --> 00:52:04.360 Any other questions? 0ad517c9-3a46-4984-8b84-e1363812cdcf-0 00:52:04.920 --> 00:52:08.080 How does the like big complicated optimization and 0ad517c9-3a46-4984-8b84-e1363812cdcf-1 00:52:08.080 --> 00:52:11.674 looking at recovery times compared to just increasing the 0ad517c9-3a46-4984-8b84-e1363812cdcf-2 00:52:11.674 --> 00:52:15.020 factors of safety on what we already do as structural 0ad517c9-3a46-4984-8b84-e1363812cdcf-3 00:52:15.020 --> 00:52:15.640 engineers? 11b18675-59e4-46d7-9c7e-ff2e13613263-0 00:52:16.360 --> 00:52:18.920 That's a good, I think that's a really important point. 3e198c66-9ba9-41ad-b3d8-37af78325632-0 00:52:19.480 --> 00:52:23.327 There may be a scenario where maybe increasing the importance 3e198c66-9ba9-41ad-b3d8-37af78325632-1 00:52:23.327 --> 00:52:27.051 factor in some areas of the US yields acceptable functional 3e198c66-9ba9-41ad-b3d8-37af78325632-2 00:52:27.051 --> 00:52:27.920 recovery time. cf64bb76-bec9-4747-a614-fb94c0b1e3cd-0 00:52:27.960 --> 00:52:31.250 And I think that's once there have been studies in the past, cf64bb76-bec9-4747-a614-fb94c0b1e3cd-1 00:52:31.250 --> 00:52:34.648 let's say a year or so that are trying to do that benchmarking cf64bb76-bec9-4747-a614-fb94c0b1e3cd-2 00:52:34.648 --> 00:52:37.400 activity to say, where does code get us right now? ac5be34d-8359-4b04-91e4-ef83b8784120-0 00:52:37.680 --> 00:52:40.970 Like there are probably some areas of the US that maybe code ac5be34d-8359-4b04-91e4-ef83b8784120-1 00:52:40.970 --> 00:52:44.476 is enough, especially if we are deciding, hey, like we're trying ac5be34d-8359-4b04-91e4-ef83b8784120-2 00:52:44.476 --> 00:52:47.713 to get to in, in, in many of these conversations I've seen, ac5be34d-8359-4b04-91e4-ef83b8784120-3 00:52:47.713 --> 00:52:50.680 by the way, it's not as granular as like, oh, 30 days. 38ec85cb-41fb-4eed-92db-1853c0263154-0 00:52:51.000 --> 00:52:53.712 A lot of the times they're saying days to weeks, weeks to 38ec85cb-41fb-4eed-92db-1853c0263154-1 00:52:53.712 --> 00:52:54.040 months. 6fc5e0e0-efe0-4daf-a9c4-f0238b62776f-0 00:52:54.040 --> 00:52:57.765 There's probably some areas of the US where maybe reducing 6fc5e0e0-efe0-4daf-a9c4-f0238b62776f-1 00:52:57.765 --> 00:53:01.491 drift limit and importance factor changes, like going risk 6fc5e0e0-efe0-4daf-a9c4-f0238b62776f-2 00:53:01.491 --> 00:53:04.080 category one to two to three could help. 140ff190-da31-4717-a7f5-649dfe5275f7-0 00:53:04.280 --> 00:53:08.234 And I actually think that the BSSC is looking at toggling 140ff190-da31-4717-a7f5-649dfe5275f7-1 00:53:08.234 --> 00:53:12.120 those factors as opposed to doing like this type of high 140ff190-da31-4717-a7f5-649dfe5275f7-2 00:53:12.120 --> 00:53:13.280 dimensional work. 48030f90-9fbd-4f4d-bb8c-8abcf3c558fc-0 00:53:13.880 --> 00:53:16.705 Isn't that basically already kind of built in, in cases where 48030f90-9fbd-4f4d-bb8c-8abcf3c558fc-1 00:53:16.705 --> 00:53:19.530 you have like the California building code as opposed to like 48030f90-9fbd-4f4d-bb8c-8abcf3c558fc-2 00:53:19.530 --> 00:53:22.401 Kansas probably doesn't have its own yeah, yeah, yeah, seismic 48030f90-9fbd-4f4d-bb8c-8abcf3c558fc-3 00:53:22.401 --> 00:53:23.040 building code. 5118a79e-c6c1-4cbe-9eb6-2911d06eb337-0 00:53:23.720 --> 00:53:24.600 That's a great point. fcf9984e-8c0e-4761-b982-9baa9c73137b-0 00:53:25.120 --> 00:53:28.343 The way I think of it is we have the template, like the fcf9984e-8c0e-4761-b982-9baa9c73137b-1 00:53:28.343 --> 00:53:31.280 provisions are a template and they have the knobs. 43f395e4-2dcb-4678-bdbf-6b13339ff8fe-0 00:53:31.800 --> 00:53:34.908 And then the question is how do we turn the knobs to achieve 43f395e4-2dcb-4678-bdbf-6b13339ff8fe-1 00:53:34.908 --> 00:53:36.080 this effective outcome? 8acf93d4-97ec-42f1-a065-7299f1c14765-0 00:53:36.520 --> 00:53:40.220 And the question that people in the BSc are asking is how, what 8acf93d4-97ec-42f1-a065-7299f1c14765-1 00:53:40.220 --> 00:53:43.515 are the places in the US where the knob even needs to be 8acf93d4-97ec-42f1-a065-7299f1c14765-2 00:53:43.515 --> 00:53:43.920 turned? 39d2a2b8-e351-4509-a1de-633a6cddf310-0 00:53:44.160 --> 00:53:46.440 And like you're saying, I think there are some regions where 39d2a2b8-e351-4509-a1de-633a6cddf310-1 00:53:46.440 --> 00:53:48.160 they probably don't even have to do anything. 866624f8-0ba3-4fbd-92d0-2fecc08d391b-0 00:53:48.320 --> 00:53:51.438 And then others, I would say, especially areas in the Bay Area 866624f8-0ba3-4fbd-92d0-2fecc08d391b-1 00:53:51.438 --> 00:53:54.507 where we have like these caps, I think these, these like risk 866624f8-0ba3-4fbd-92d0-2fecc08d391b-2 00:53:54.507 --> 00:53:57.477 caps, like that's, I think those are the places where we're 866624f8-0ba3-4fbd-92d0-2fecc08d391b-3 00:53:57.477 --> 00:54:00.200 probably going to need to turn things off quite a bit. b9418431-dfe9-4c54-8b03-7ea0a3c47b7d-0 00:54:00.200 --> 00:54:02.967 And, and there's actually another point there, which is b9418431-dfe9-4c54-8b03-7ea0a3c47b7d-1 00:54:02.967 --> 00:54:05.931 like who gets to decide what the, what the performance goal b9418431-dfe9-4c54-8b03-7ea0a3c47b7d-2 00:54:05.931 --> 00:54:06.080 is? 48a64853-9e55-4a97-81ce-500f2eed04b5-0 00:54:06.120 --> 00:54:07.320 And this is something I wrote about. 53b02b6a-3d79-47c7-85e8-7f8f776d29e4-0 00:54:08.000 --> 00:54:10.735 There's a lot of, a lot of debate in this area about 53b02b6a-3d79-47c7-85e8-7f8f776d29e4-1 00:54:10.735 --> 00:54:13.833 whether or not it should be based on benefit cost analysis, 53b02b6a-3d79-47c7-85e8-7f8f776d29e4-2 00:54:13.833 --> 00:54:15.640 revealed or expressed preferences. fe6ee5d8-038e-4d1f-9589-488ab6c318bb-0 00:54:16.080 --> 00:54:18.920 And I think it's honestly a fascinating topic. 6555396f-c12c-4387-9625-238e9a121ebe-0 00:54:19.400 --> 00:54:22.183 But what I, what I see is missing a lot of times is 6555396f-c12c-4387-9625-238e9a121ebe-1 00:54:22.183 --> 00:54:25.555 societal elicitation and asking people, what do you expect out 6555396f-c12c-4387-9625-238e9a121ebe-2 00:54:25.555 --> 00:54:26.679 of the building code? 124bb5dd-f9ed-400f-90b9-fd50a4f17ce5-0 00:54:26.880 --> 00:54:29.169 And I think the spur report that I showed in the first slide is a 124bb5dd-f9ed-400f-90b9-fd50a4f17ce5-1 00:54:29.169 --> 00:54:30.800 good example of what happens when you do that. b8f31646-7a7a-40e1-928d-9a765d27b16a-0 00:54:31.120 --> 00:54:34.057 But I don't think it's being done nearly enough in places in b8f31646-7a7a-40e1-928d-9a765d27b16a-1 00:54:34.057 --> 00:54:37.139 the US where I think the public is generally unaware about what b8f31646-7a7a-40e1-928d-9a765d27b16a-2 00:54:37.139 --> 00:54:38.679 the building code even delivers. 116bb7bf-d0b7-48cc-878e-d3f8c543ff46-0 00:54:38.680 --> 00:54:43.720 Basically, great presentation. de6a43d5-90cc-4060-a762-4cad84263657-0 00:54:43.720 --> 00:54:44.560 Omar, as always. f9926b55-2eb2-4e36-a402-8cbb4b744452-0 00:54:46.320 --> 00:54:48.920 I want to go back to the first part of your presentation. 5db53643-dc6a-4f07-9e5b-c86eabc9ce6e-0 00:54:49.480 --> 00:54:54.072 And you were talking about the the goal for functional recovery 5db53643-dc6a-4f07-9e5b-c86eabc9ce6e-1 00:54:54.072 --> 00:54:58.522 and the check for so recovery and basically the goal you were 5db53643-dc6a-4f07-9e5b-c86eabc9ce6e-2 00:54:58.522 --> 00:55:03.043 you you want to see all ground motion intensity levels and the 5db53643-dc6a-4f07-9e5b-c86eabc9ce6e-3 00:55:03.043 --> 00:55:04.120 check just one. c0d54c73-2de1-4e42-8ccf-ff8a90a4cbc3-0 00:55:05.600 --> 00:55:05.840 So what? f7ab9b61-90f2-408b-b39d-659fb5e00a77-0 00:55:05.960 --> 00:55:11.079 So my question is, why should we, why should we go for the f7ab9b61-90f2-408b-b39d-659fb5e00a77-1 00:55:11.079 --> 00:55:11.600 check? cc07c9e1-c676-4c92-858f-2cd7d1ccca28-0 00:55:13.640 --> 00:55:18.525 Is it reasonable to instead go for the goal or or the goal will cc07c9e1-c676-4c92-858f-2cd7d1ccca28-1 00:55:18.525 --> 00:55:22.800 be the check of check the goal directly and not do that cc07c9e1-c676-4c92-858f-2cd7d1ccca28-2 00:55:22.800 --> 00:55:24.480 simplified assessment? b50434a9-45f8-43e5-bdda-060144533ad0-0 00:55:25.360 --> 00:55:29.754 Because I, I once did a FEMA P58 type analysis for a building and b50434a9-45f8-43e5-bdda-060144533ad0-1 00:55:29.754 --> 00:55:33.882 most of the time that I spent trying to do the thing was, was b50434a9-45f8-43e5-bdda-060144533ad0-2 00:55:33.882 --> 00:55:35.680 not running the simulation. 87ea9c8d-6ab6-4a99-ad31-db8c6eb94ec2-0 00:55:35.680 --> 00:55:37.560 It was actually building or or. 0c01e6a3-376d-4a48-9bd9-df4ce71a61d4-0 00:55:37.920 --> 00:55:41.760 So the most of the time is not in running the analysis. 98b7aa95-5a8e-46b5-9a52-8542209e46ff-0 00:55:41.760 --> 00:55:45.448 So, so, so basically if, well, I mean, what I've seen is that if 98b7aa95-5a8e-46b5-9a52-8542209e46ff-1 00:55:45.448 --> 00:55:48.852 you check different almost intensity measures, it's like go 98b7aa95-5a8e-46b5-9a52-8542209e46ff-2 00:55:48.852 --> 00:55:52.200 view do instead of 1, you do 10 almost intensity measures. 9c434120-c028-43e9-95e0-8e31953a20ba-0 00:55:52.440 --> 00:55:56.479 OK, whatever you're running is going to take 10 more, 10 times 9c434120-c028-43e9-95e0-8e31953a20ba-1 00:55:56.479 --> 00:55:56.800 more. f427b964-bfc5-4a5e-83e5-6999eb2bbf52-0 00:55:57.040 --> 00:56:00.030 But it's not, that's not where you spend all your time when f427b964-bfc5-4a5e-83e5-6999eb2bbf52-1 00:56:00.030 --> 00:56:02.871 you, when you're doing something for a real building and f427b964-bfc5-4a5e-83e5-6999eb2bbf52-2 00:56:02.871 --> 00:56:03.320 practice. 1fbe41c0-74c3-4290-98d3-aae34a899160-0 00:56:03.320 --> 00:56:04.760 So what's your opinion about that? 925cede9-1482-484d-8ddc-d9501989938b-0 00:56:04.760 --> 00:56:10.502 And is it reasonable to to ask like practicing engineers to 925cede9-1482-484d-8ddc-d9501989938b-1 00:56:10.502 --> 00:56:12.800 check directly the goal? 44f993b6-755d-4348-876a-10d7b85a2e84-0 00:56:13.680 --> 00:56:15.600 Yes, No, this is very important. 8bf4c63c-e732-416e-a197-1147ef6f60f6-0 00:56:15.600 --> 00:56:18.273 And if this is ever recorded, just know that I'm not trying to 8bf4c63c-e732-416e-a197-1147ef6f60f6-1 00:56:18.273 --> 00:56:19.080 create controversy. c32d68f8-3834-40fe-8519-ae36d2280f7e-0 00:56:19.680 --> 00:56:23.782 I would say that for this type of to clarify this type of c32d68f8-3834-40fe-8519-ae36d2280f7e-1 00:56:23.782 --> 00:56:27.885 context or framing feels a little more appropriate in the c32d68f8-3834-40fe-8519-ae36d2280f7e-2 00:56:27.885 --> 00:56:32.058 context of provisions where maybe we're not running a FEMA c32d68f8-3834-40fe-8519-ae36d2280f7e-3 00:56:32.058 --> 00:56:33.119 P50 assessment. 7521a7a9-e2c3-4350-9285-fa3b52bf1e74-0 00:56:33.360 --> 00:56:37.252 Instead, we're calibrating maybe an ELF type procedure that would 7521a7a9-e2c3-4350-9285-fa3b52bf1e74-1 00:56:37.252 --> 00:56:41.027 by proxy achieve the check kind of how we're doing it with life 7521a7a9-e2c3-4350-9285-fa3b52bf1e74-2 00:56:41.027 --> 00:56:41.439 safety. 2291a884-2539-48fd-90e9-77cd2611cf90-0 00:56:41.920 --> 00:56:44.720 Because you're right, if this was a FEMA P 58 assessment, I 2291a884-2539-48fd-90e9-77cd2611cf90-1 00:56:44.720 --> 00:56:47.706 would totally just do the life the the time based assessment or 2291a884-2539-48fd-90e9-77cd2611cf90-2 00:56:47.706 --> 00:56:49.760 the risk based assessment get to my answer. cecf9b7e-055e-4b89-8f5d-bcb4b357086e-0 00:56:50.840 --> 00:56:54.067 But if we are doing if we're dealing with folks who may not cecf9b7e-055e-4b89-8f5d-bcb4b357086e-1 00:56:54.067 --> 00:56:57.402 have access to the inputs and the data necessary to running a cecf9b7e-055e-4b89-8f5d-bcb4b357086e-2 00:56:57.402 --> 00:57:00.899 full blown FEMA P50 assessment, then this would be this checking cecf9b7e-055e-4b89-8f5d-bcb4b357086e-3 00:57:00.899 --> 00:57:03.320 procedure would be more well suited to them. b8345c2a-4748-4131-9dd3-8183f9ada73d-0 00:57:03.720 --> 00:57:08.327 Now you may ask me, well, Omar, checking one point is is kind of b8345c2a-4748-4131-9dd3-8183f9ada73d-1 00:57:08.327 --> 00:57:09.320 a gamble here. 00b86e28-9c1e-4dcb-8982-fc665bc5212f-0 00:57:09.320 --> 00:57:10.440 Why don't we just check 2? bd34fb19-6a51-4fe8-adf0-5c07e67e0316-0 00:57:10.960 --> 00:57:14.810 And that is, I would say been a much more of a debate than I bd34fb19-6a51-4fe8-adf0-5c07e67e0316-1 00:57:14.810 --> 00:57:18.725 thought because in in the, I would say structural engineering bd34fb19-6a51-4fe8-adf0-5c07e67e0316-2 00:57:18.725 --> 00:57:22.323 community, there's a lot of pushback on having to do the bd34fb19-6a51-4fe8-adf0-5c07e67e0316-3 00:57:22.323 --> 00:57:25.480 work twice for a single building on these checks. 19a5c64f-3a6c-429f-bab6-0d2ffd5921f0-0 00:57:25.480 --> 00:57:28.025 Even though some standards like the tall building initiative, 19a5c64f-3a6c-429f-bab6-0d2ffd5921f0-1 00:57:28.025 --> 00:57:30.325 there are these guidelines for tall buildings where you 19a5c64f-3a6c-429f-bab6-0d2ffd5921f0-2 00:57:30.325 --> 00:57:32.871 implicitly do have to check like a design level and a service 19a5c64f-3a6c-429f-bab6-0d2ffd5921f0-3 00:57:32.871 --> 00:57:34.760 level, like you're checking 2 ground motions. 05565e18-ef05-4aca-975f-99e2ae7d33eb-0 00:57:35.240 --> 00:57:39.407 But for the average building, the 99%, many people would push 05565e18-ef05-4aca-975f-99e2ae7d33eb-1 00:57:39.407 --> 00:57:43.036 back against doing getting another pinch point on the 05565e18-ef05-4aca-975f-99e2ae7d33eb-2 00:57:43.036 --> 00:57:43.440 curve. 62d300c0-65fd-4636-be40-313f2fbac596-0 00:57:43.800 --> 00:57:47.218 I am a as a non practicing structural engineer, I am very 62d300c0-65fd-4636-be40-313f2fbac596-1 00:57:47.218 --> 00:57:48.280 much Pro 2 points. 52df2048-b70f-457a-a434-6c381111df4f-0 00:57:48.560 --> 00:57:51.336 But I'd say many people have, you know, strong feelings about 52df2048-b70f-457a-a434-6c381111df4f-1 00:57:51.336 --> 00:57:51.560 that. 688f3474-5c2c-4ea6-bf7d-716c5575763d-0 00:57:51.680 --> 00:57:54.525 So this research would at least help those who insist on having 688f3474-5c2c-4ea6-bf7d-716c5575763d-1 00:57:54.525 --> 00:57:57.371 one point or if it is embedded in the provisions would at least 688f3474-5c2c-4ea6-bf7d-716c5575763d-2 00:57:57.371 --> 00:58:00.083 give you some confidence about if we're going to choose one, 688f3474-5c2c-4ea6-bf7d-716c5575763d-3 00:58:00.083 --> 00:58:01.640 what would be like the best place? 9e91bd8e-39ef-46de-a323-251950dbfd95-0 00:58:05.520 --> 00:58:06.360 That's a very good question. 6805057b-6111-43a9-b8d3-81e837494abb-0 00:58:08.400 --> 00:58:09.000 Anybody else? 24b99616-ed3f-4af7-9e1c-9c87206e62bb-0 00:58:11.160 --> 00:58:12.000 Yes, Chris. b6127f88-46c5-4776-ad88-ca04e905e841-0 00:58:12.240 --> 00:58:15.760 So I don't think about building stiffness hardly ever. f0617b55-6916-4823-9b14-f523c36506e7-0 00:58:16.080 --> 00:58:19.850 So this might be a silly question, but you showed the f0617b55-6916-4823-9b14-f523c36506e7-1 00:58:19.850 --> 00:58:23.482 dependence of some of your results on the stiffness f0617b55-6916-4823-9b14-f523c36506e7-2 00:58:23.482 --> 00:58:27.671 modifications that you might take when you're designing for f0617b55-6916-4823-9b14-f523c36506e7-3 00:58:27.671 --> 00:58:28.440 resilience. e31697c4-ba3d-46dd-818b-6448d668e4f7-0 00:58:29.200 --> 00:58:32.994 How much do individual building designs, as they have been e31697c4-ba3d-46dd-818b-6448d668e4f7-1 00:58:32.994 --> 00:58:36.981 created, influence changes and stiffness that are inherent to e31697c4-ba3d-46dd-818b-6448d668e4f7-2 00:58:36.981 --> 00:58:40.839 any improvement you might make before you've done anything? cd56411a-8074-45ac-9910-a56bdca1422c-0 00:58:40.840 --> 00:58:43.040 I don't know if that made sense. 12818f58-1dc9-42b2-a5e7-cc5092d4ad84-0 00:58:43.040 --> 00:58:44.080 Let me try and restate that. 764ab7d4-0f72-423d-8900-9949c588cae1-0 00:58:44.080 --> 00:58:47.730 Like how much does an initial building design control the 764ab7d4-0f72-423d-8900-9949c588cae1-1 00:58:47.730 --> 00:58:48.360 stiffness? c68eabf5-552c-490c-a87c-8c24b9cffd0f-0 00:58:48.360 --> 00:58:52.689 And can you control for that when you're trying to understand c68eabf5-552c-490c-a87c-8c24b9cffd0f-1 00:58:52.689 --> 00:58:56.600 what components you need to build into your new design? 8657679f-6478-4598-9130-b3f36d475f65-0 00:58:57.000 --> 00:58:57.720 Yeah, no, that's it. 51e414b3-7ee7-4d66-882c-062948c84094-0 00:58:57.720 --> 00:58:59.160 That's a great, a great question. f1d8c436-4e68-497d-8e76-864dd95c0ed7-0 00:58:59.160 --> 00:59:01.494 I think like there's an interdependence between, for f1d8c436-4e68-497d-8e76-864dd95c0ed7-1 00:59:01.494 --> 00:59:04.269 example, I think the first step you would probably do when you f1d8c436-4e68-497d-8e76-864dd95c0ed7-2 00:59:04.269 --> 00:59:06.120 design a new building, this is very easy. d3297a19-9f6f-44f8-9e56-2c4d4e477d99-0 00:59:06.120 --> 00:59:07.480 This is much easier for new buildings. fbf7cd62-fa1f-44ca-b094-8e95fabd54c5-0 00:59:07.840 --> 00:59:09.600 Like let's say we're about to design some new. b49dc4b4-647f-48c4-8005-54d0e0c7242e-0 00:59:09.840 --> 00:59:12.280 The first question is what's the lateral force resistance system? dfd104c5-0f71-4341-bf41-f8bad790c410-0 00:59:12.600 --> 00:59:15.669 Steel, very flexible concrete shear wall would probably be dfd104c5-0f71-4341-bf41-f8bad790c410-1 00:59:15.669 --> 00:59:18.894 more stiff and then that would influence probably the type of dfd104c5-0f71-4341-bf41-f8bad790c410-2 00:59:18.894 --> 00:59:21.651 as we saw the type of non structural line structural dfd104c5-0f71-4341-bf41-f8bad790c410-3 00:59:21.651 --> 00:59:23.160 components we would bring in. 739a912f-a39f-4558-9248-222c22f47a92-0 00:59:23.360 --> 00:59:26.259 But if we think about it, a lot of those components would come 739a912f-a39f-4558-9248-222c22f47a92-1 00:59:26.259 --> 00:59:26.720 in anyway. 710daf15-f605-4c34-93ee-19d3afc3d0e9-0 00:59:26.920 --> 00:59:29.220 The question is when we do something special to them to 710daf15-f605-4c34-93ee-19d3afc3d0e9-1 00:59:29.220 --> 00:59:31.520 achieve, you know, the target where we're trying to go. 1ca18177-7246-456a-817c-3b8e7ba58771-0 00:59:32.160 --> 00:59:35.186 I would say that as of right now, and this is I guess maybe 1ca18177-7246-456a-817c-3b8e7ba58771-1 00:59:35.186 --> 00:59:38.363 not necessarily answering the question directly, a lot of this 1ca18177-7246-456a-817c-3b8e7ba58771-2 00:59:38.363 --> 00:59:40.280 work is done through trial and error. 904ea6ca-ac04-46e5-a716-ae80d5008208-0 00:59:40.720 --> 00:59:44.038 Like we're trying to see, you know, through some of the 904ea6ca-ac04-46e5-a716-ae80d5008208-1 00:59:44.038 --> 00:59:47.475 software solutions I was mentioning, OK, like if I choose 904ea6ca-ac04-46e5-a716-ae80d5008208-2 00:59:47.475 --> 00:59:50.319 this type of system, am I getting to my target? 7bbae41c-ed6c-4ddc-914d-a0bd355ebfd6-0 00:59:50.320 --> 00:59:52.153 OK, I'm going to change these three non structural, I'm going 7bbae41c-ed6c-4ddc-914d-a0bd355ebfd6-1 00:59:52.153 --> 00:59:53.040 to am I getting to the target? efe6d7d9-e520-4b4a-b8cf-6ed1e6f4b998-0 00:59:53.040 --> 00:59:55.323 Whereas the optimization approach just does everything efe6d7d9-e520-4b4a-b8cf-6ed1e6f4b998-1 00:59:55.323 --> 00:59:57.440 head to end all at once to give you what you need. dc3e791c-4d2a-4e13-a74e-62822bafa54b-0 00:59:57.880 --> 01:00:02.121 But to your observation and point with these assessments dc3e791c-4d2a-4e13-a74e-62822bafa54b-1 01:00:02.121 --> 01:00:06.735 here, and this is kind of like a minor detail that I think is dc3e791c-4d2a-4e13-a74e-62822bafa54b-2 01:00:06.735 --> 01:00:08.000 worth mentioning. 64a6fb13-3a95-4e8f-a899-6db0f473a82a-0 01:00:08.760 --> 01:00:12.760 The reason I showed you the results in this format. 63e0adb8-4ab8-4475-9fdd-7a4563f0d518-0 01:00:13.880 --> 01:00:14.360 Here. feecd7c0-bb5b-4b32-8216-bc81a8b9c4c5-0 01:00:14.400 --> 01:00:18.280 So the reason why I showed you guys the results in this format feecd7c0-bb5b-4b32-8216-bc81a8b9c4c5-1 01:00:18.280 --> 01:00:21.853 is because the optimization was only doing things or only feecd7c0-bb5b-4b32-8216-bc81a8b9c4c5-2 01:00:21.853 --> 01:00:24.440 considering non structural interventions. ceffc8bd-8150-44a2-a518-c296d54e864b-0 01:00:25.160 --> 01:00:28.318 I think what you're getting to, which I think is a much more ceffc8bd-8150-44a2-a518-c296d54e864b-1 01:00:28.318 --> 01:00:31.373 appropriate and efficient way of doing this, is to include ceffc8bd-8150-44a2-a518-c296d54e864b-2 01:00:31.373 --> 01:00:34.480 structural and non structural interventions simultaneously. 0c464a14-7d2d-46b0-b97b-c2e550667870-0 01:00:34.640 --> 01:00:37.899 And then do a non structural structural, non structural, like 0c464a14-7d2d-46b0-b97b-c2e550667870-1 01:00:37.899 --> 01:00:41.105 a fully integrated approach where we can sift through all of 0c464a14-7d2d-46b0-b97b-c2e550667870-2 01:00:41.105 --> 01:00:44.101 these structural and non structural improvements and say 0c464a14-7d2d-46b0-b97b-c2e550667870-3 01:00:44.101 --> 01:00:46.520 what is resource optimal and from both sides. a7f4835d-8b6f-4836-823a-c3ab803bc365-0 01:00:47.400 --> 01:00:50.448 The reason why that didn't happen here is because the a7f4835d-8b6f-4836-823a-c3ab803bc365-1 01:00:50.448 --> 01:00:53.552 surrogate model architecture that I calibrated had the a7f4835d-8b6f-4836-823a-c3ab803bc365-2 01:00:53.552 --> 01:00:56.826 engineering demand parameters featurized and then the non a7f4835d-8b6f-4836-823a-c3ab803bc365-3 01:00:56.826 --> 01:00:59.761 structural component improvements here, but I never a7f4835d-8b6f-4836-823a-c3ab803bc365-4 01:00:59.761 --> 01:01:02.640 had an auxiliary model for the structural changes. 876031f0-7d7f-41cf-8c09-686506515b0c-0 01:01:02.880 --> 01:01:06.672 So to compensate for that, I simply repeated the optimization 876031f0-7d7f-41cf-8c09-686506515b0c-1 01:01:06.672 --> 01:01:10.160 3 times using three different structural configurations. 1dc54c02-9cce-44bd-8a46-22270f5ea2b7-0 01:01:10.520 --> 01:01:14.476 If I were to expand on this, I would totally just put them all 1dc54c02-9cce-44bd-8a46-22270f5ea2b7-1 01:01:14.476 --> 01:01:16.360 together, if that makes sense. e54037c2-9497-4f77-b071-53ee622122a8-0 01:01:17.720 --> 01:01:18.000 Awesome. c5b0e006-b685-4cfa-b676-50fab45a1be9-0 01:01:18.000 --> 01:01:19.760 This is this is, this is a good question. ce009713-e93b-4e66-92e2-73965547453f-0 01:01:21.560 --> 01:01:26.010 OK, Well, any other questions, please find Omar after or during ce009713-e93b-4e66-92e2-73965547453f-1 01:01:26.010 --> 01:01:27.680 lunch or this afternoon. 89484921-8209-4e4c-abb5-a882fe83dc5e-0 01:01:27.680 --> 01:01:33.773 And for those of us joining for lunch, please meet out by the 89484921-8209-4e4c-abb5-a882fe83dc5e-1 01:01:33.773 --> 01:01:38.000 elevators on the second floor about 11:50. 20453604-21b7-4813-8dde-4cd6f3062f31-0 01:01:38.560 --> 01:01:40.880 And let's give Omar another round of applause.