Implementation of SCEC Research for Seismic Risk Reduction

总结。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。所有任务都涉及与地震工程师和通过SCEC新的实施接口协调的其他终端用户社区的合作。将设立一个由美国地质勘探局、美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的活动与美国地质勘探局和CGS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：制作用于基于性能的地震工程(PBEE)的地震动时程。地震动时程是测试设施和基于计算机的结构动力分析的必要输入，工程师将使用这些分析来开发PBEE。在这项任务中，我们将使用经过测试的代码来生成一个由震级、距离和土壤条件参数化为参数的模拟时间历史数据库。该数据库将促进NEES联盟和美国国家科学基金会的三个地震工程研究中心的地球科学应用，并将加强由加利福尼亚强动仪器项目和PEER-LIFLINES(PEER-LL)方案赞助的设计地震动图书馆项目。下一代衰减(NGA)项目由SCEC、Peer-LifeLine和美国地质勘探局共同发起，将开发一套新的地壳浅层地震地面运动衰减模型。SCEC已经致力于当前阶段，NGA-E(经验)，旨在更新从记录的强震数据得出的衰减关系。这项提议要求支持SCEC在下两个阶段中的作用，NGA-H(混合)将包括模拟和记录的地面运动，以及NGA-F将开发构造-位移模型。NGA产品将满足加州运输公司、加州能源委员会和PG&Amp；E的明确声明的需求，以及地震工程实践的广泛需求。任务3：为洛杉矶的情景地震产生地面运动和结构模拟。SCEC最近的研究量化了普恩特山盲推系统上的主要潜在地震。任务3将利用这些信息来构建来自PHT和洛杉矶地区其他危险来源的宽带地面运动的现实场景，并将聘请地震工程师评估其影响。将进行一项使用J.Hall的非线性结构模拟程序的初步研究，以量化普恩特山地震对洛杉矶市中心建筑物的影响，并使用结果来评估现有的程序条款。减少地震风险是系统层面问题的一个主要例子，需要广泛的跨学科合作和对新出现的现象的关注。拟议的计划将从这个系统级别的角度解决减少地震风险的问题，并将促进对震源物理和由此产生的地面运动之间关系的基本理解--这是SCEC研究计划的主要目标。拟议的计划将应用SCEC的基础研究来指导地震工程和风险评估的研究人员和实践者使用的新的地面运动预测模型和地面运动时间历史的开发。通过与国家科学基金会开展的防震工程活动的密切协调(见所附信函)，预计该项目将对如何利用基础地球科学降低地震风险产生全国影响。

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.