Implementation of SCEC Research for Seismic Risk Reduction

摘要南加州地震中心（SCEC）要求2.6年的资金支持三项任务，将SCEC的基础研究成果转化为直接用于减少地震风险的产品。所有的任务都涉及与地震工程师和其他用户社区的合作，通过SCEC新的实现接口进行协调。将设立一个由美国地质勘探局、中国地质勘探局和最终用户组织的代表组成的SCEC产品审查小组，以确保SCEC活动与美国地质勘探局和中国地质勘探局的灾害计划相协调，并确保产品得到适当的描述、记录和传播。任务1：产生用于基于性能的地震工程（PBEE）的地震动时程。地面运动的时间历程是必要的输入到测试设施和基于计算机的结构动力分析，工程师将使用开发PBEE。模拟的宽带时程需要增加记录的接近大地震时程的有限集合。在这项任务下，我们将使用测试的代码来产生一个由震级、距离和土壤条件参数化的模拟时程的广泛数据库。该数据库将促进NEES联合会和三个NSF地震工程研究中心的地球科学应用，并将增强由加州强震仪器项目和PEER生命线（PEER-LL）计划赞助的设计地震动库项目。由SCEC、PEER-Lifelines和USGS共同发起的下一代衰减（NGA）项目将开发一套新的浅层地壳地震地面运动衰减模型。SCEC已经致力于当前阶段，NGA-E（经验），其目的是更新从记录的强震数据得出的衰减关系。这一建议要求支持SCEC在接下来的两个阶段中的作用，NGA-H（混合），它将包括模拟和记录的地面运动，NGA-F，它将开发一个构造位移模型。NGA的产品将满足加州交通、加州能源委员会、PG& E以及地震工程实践的明确需求。任务3：为洛杉矶的情景地震生成地面运动和结构模拟。最近的SCEC研究已经量化了Puente Hills盲推力系统上的主要潜在地震。任务3将利用这些信息构建LA地区PHT和其他危险源的宽带地面运动的现实情景，and it will engage从事earthquake地震engineers工程师in assessing评估the implications含义.一个试点研究采用J.霍尔的非线性结构模拟代码将进行量化的影响，一个普恩特山地震的建筑物在洛杉矶市中心，并使用的结果来评估当前的代码规定。减少地震风险是一个系统级问题的典型例子，需要广泛的跨学科合作和对紧急现象的关注。拟议的计划将从这个系统层面的角度来解决地震风险降低的问题，它将推进震源物理和由此产生的地面运动之间的关系的基本理解-SCEC研究计划的一个主要目标。该计划将应用SCEC的基础研究来指导地震工程和风险评估的研究人员和从业人员使用的新的地震动预测模型和地震动时程的发展。通过与NSF赞助的地震工程活动（见所附信件）的密切协调，该项目有望对如何利用基础地球科学降低地震风险产生全国性的影响。

Summary. The Southern California Earthquake Center (SCEC) requests 2.6 years of funding to supportthree tasks that will translate SCEC's basic-research accomplishments into products for direct use inearthquake risk reduction. All of the tasks involve collaborations with earthquake engineers and otherend-user communities coordinated through SCEC's new Implementation Interface. A SCEC ProductReview Panel, comprising representatives from the USGS, CGS, and end-user organizations, will be setup to ensure that SCEC activities are coordinated with the USGS and CGS hazard programs and thatproducts are appropriately described, documented, and disseminated.Task 1: Produce ground-motion time histories for use in performance-based earthquake engineering(PBEE). Ground-motion time histories are necessary input into testing facilities and computer-baseddynamic analysis of structures that engineers will use to develop PBEE. Simulated broadband timehistories are needed to augment the limited set of recorded time histories close to large earthquakes.Under this task, we will use tested codes to produce a extensive database of simulated time historiesparameterized by magnitude, distance, and soil conditions. The database will facilitate geoscienceapplications by the NEES Consortium and the three NSF Earthquake Engineering Research Centers, andit will augment the Design Ground Motion Library Project, sponsored by the California Strong MotionInstrumentation Project and by the PEER-Lifelines (PEER-LL) Program.Task 2: Participate in Next Generation Attenuation (NGA) Project. The Next Generation Attenuation(NGA) Project, co-sponsored by SCEC, PEER-Lifelines and the USGS, will develop a new suite ofground-motion attenuation models for shallow crustal earthquakes. SCEC is already committed to thecurrent phase, NGA-E (Empirical), which aims to update attenuation relationships derived from recordedstrong motion data. This proposal requests support for SCEC's role in the next two phases, NGA-H(Hybrid), which will incorporate both simulated and recorded ground motions, and NGA-F, which willdevelop a tectonic-displacement model. NGA products will fulfill a clearly stated need of Caltrans, theCalifornia Energy Commission, and PG&E, and of earthquake engineering practice at large.Task 3: Produce Ground-Motion and Structural Simulations for Scenario Earthquakes in Los Angeles.Recent SCEC research has quantified major potential earthquakes on the Puente Hills blind thrust system.Task 3 will utilize this information to construct realistic scenarios for broadband ground motions from thePHT and other hazardous sources in the LA region, and it will engage earthquake engineers in assessingthe implications. A pilot study employing J. Hall's nonlinear structural simulation code will beundertaken to quantify the effects of a Puente Hills earthquake on buildings in downtown Los Angelesand use the results to evaluate current code provisions.Intellectual Merit. Reducing earthquake risk is a prime example of a system-level problem requiringbroad interdisciplinary collaboration and attention to emergent phenomena. The proposed program willaddress the issues of earthquake risk reduction from this system-level perspective, and it will advance thefundamental understanding of the relationship between earthquake source physics and resulting groundmotions -- a major goal of the SCEC research program.Broader Impacts. The proposed program will apply SCEC basic research to guide the development ofthe new ground-motion prediction models and ground-motion time histories used by researchers andpractitioners of earthquake engineering and risk assessment. Through the close coordination with NSFsponsoredearthquake engineering activities (see attached letters), this project can be expected to have anationwide impact on how basic geoscience is utilized to reduce seismic risk.