NEESR-SG: Soil Improvement Strategies to Mitigate Impact of Seismic Ground Failures via Novel Integration of Experiment and Simulation

该奖项是美国国家科学基金会07-506项目招标“小乔治·e·布朗地震工程模拟网络（NEES）研究”竞赛的结果。该项目由伊利诺伊大学厄巴纳-香槟分校领导，并授予瓦尔帕莱索大学一个子奖项。地震引起的地面破坏是地震造成经济损失的一个普遍且日益严重的原因。同时，国家不断增长的基础设施需求需要更多更大的桥梁，增加跨度和交通量，因此需要使用大直径轴组或重力沉箱等大型刚性基础。当地震引起的地面破坏发生时，这些基础必须承受巨大但未知的横向力。一种常见的解决方案是保守地修复大块容易破裂的土壤，这涉及到高昂的建设成本、增加的施工时间和更大的环境影响。该项目将评估新的地面改善几何形状，如v形和拱形，以“偏转”横向移动的土壤，从而减少：(1)大型基础单元的横向载荷；(2)地面改善费用；(3)时间和环境影响。这将通过创新的离心机实验（在伦斯勒理工学院的NEES设备现场进行）和使用地震工程模拟软件开放系统的自我学习模拟（SelfSim）来完成。这种整合被称为“仿真设计的实验-实验驱动的仿真”（SDE-EDS）。这种新颖的集成将产生强大的减轻地震引起的地面破坏的策略，可以在基于性能的地震工程环境中实施。除了通过降低地面改善成本、环境影响和施工时间来减少地面故障对社会的影响外，其他更广泛的影响包括：(1)为未来基于地基性能和地面改善的地震工程研究开辟了新的途径；(2)启动瓦尔帕莱索大学和伊利诺伊大学厄巴纳-香槟分校之间的教育交流，以扩大学生接触研究的机会，并为实践做好更好的准备。该项目的数据将通过NEES数据存储库（http://www.nees.org）提供。

This award is an outcome of the National Science Foundation 07-506 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research" competition. This project is led by the University of Illinois at Urbana-Champaign and includes a subaward to Valparaiso University. Seismically-induced ground failures are a pervasive and growing source of economic loss from earthquakes. Concurrently, the nation's growing infrastructure needs demand more and larger bridges with increased spans and traffic volumes, thus requiring the use of large, stiff foundations such as large diameter shaft groups or gravity caissons. When seismically-induced ground failures occur, these foundations must contend with large, but unknown lateral forces. A common solution is to conservatively remediate large blocks of soil susceptible to failure, which involves high construction costs, increased construction time, and greater environmental impacts. This project will evaluate novel ground improvement geometries, such as chevrons and arches, to "deflect" laterally moving soil thereby reducing: (1) lateral loads on large foundation elements; (2) ground improvement costs; and (3) time and environmental impacts. This will be accomplished via an innovative integration of centrifuge experiments (performed at the NEES equipment site at Rensselaer Polytechnic Institute) and Self-Learning Simulations (SelfSim) using the Open System for Earthquake Engineering Simulation software. This integration is termed "Simulation-designed Experiment - Experiment-driven Simulation" (SDE-EDS).This novel integration will result in robust mitigation strategies for seismically-induced ground failure that can be implemented in a performance-based earthquake engineering environment. Besides reducing societal impacts from ground failures by reducing ground improvement costs, environmental impacts, and construction time, other broader impacts include: (1) opening new avenues for future performance-based earthquake engineering studies involving foundation performance and ground improvement; and (2) initiating an educational exchange between Valparaiso University and the University of Illinois at Urbana-Champaign to expand student exposure to research and better prepare them for practice. Data from this project will be made available through the NEES data repository (http://www.nees.org).