Effects of Liquefaction on Structures in Christchurch

液化对基督城结构的影响

• 批准号: 1332501
• 负责人: Jonathan Bray
• 金额: $ 39.99万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1332501&HistoricalAwards=false
• 关键词: Effects; Liquefaction; Structures; Christchurch

Conventional liquefaction evaluation procedures cannot explain the different levels of liquefaction-induced building damage that occurred in Christchurch, New Zealand during the 2010-2011 Canterbury earthquake sequence. Each event with its different effects on structures warrants further study. Performance based earthquake engineering requires robust analytical tools that can discern varying levels of seismic performance. The 2010-2011 Canterbury earthquake sequence, with its excellent recordings of ground motions, its comprehensive subsurface investigation program, and its well-documented performance of structures in Christchurch, provides an exceptional opportunity to advance liquefaction evaluation tools. With the limitations inherent in investigating liquefaction effects solely in the laboratory or through numerical simulations, there is a pressing need to use these well-documented case histories to gain insights and to develop improved analytical procedures. The quantity and quality of the ground characterization and ground failure data in Christchurch are unparalleled. Thus, they provide a unique opportunity for advancing knowledge and practice in liquefaction engineering. Sampling and advanced cyclic testing of the troublesome silty sands in Christchurch is performed to characterize their cyclic resistance. This work enables comprehensive documentation of insightful case histories of building performance at sites undergoing different levels of liquefaction-induced ground failure. Fully nonlinear effective stress back-analyses of the case histories evaluate the importance of soil-structure interaction effects for buildings at liquefaction sites. Additionally, a liquefaction outreach website will bring liquefaction into the classrooms. Learning from design level earthquakes is invaluable to advancing the earthquake profession. Liquefaction effects research is vitally important in the U.S. where the occurrence of the massive liquefaction that occurred in Christchurch could literally destroy a city. The similarity of the Christchurch liquefaction hazards and infrastructure with those in the U.S. means that the research findings will be directly transferable to U.S. cities of comparable size, as well as scalable to larger urban centers. The 2010-2011 Canterbury earthquake sequence provides the opportunity for an integrated study of blocks of buildings at a degree of detail and level of complexity that could not be performed in the U.S. due to security restrictions. Importantly, the research focuses on the effects of liquefaction on structures as opposed to the phenomenon itself, thus advancing the state-of-the-practice in liquefaction engineering. The project supports continued international collaborations between New Zealand and U.S. earthquake researchers and allows a U.S. Ph.D. student to establish research contacts in New Zealand.

传统的液化评估程序无法解释2010-2011年坎特伯雷地震序列期间新西兰基督城发生的不同程度的液化引起的建筑物损坏。每个事件对结构的不同影响都值得进一步研究。 基于性能的地震工程需要强大的分析工具，可以辨别不同级别的抗震性能。 2010-2011年的坎特伯雷地震序列，其出色的地面运动记录，其全面的地下调查计划，以及其在基督城的结构性能记录良好，提供了一个特殊的机会，以推进液化评价工具。 由于仅在实验室或通过数值模拟调查液化效应的固有局限性，迫切需要使用这些有据可查的案例历史来获得见解并开发改进的分析程序。 基督城的地面特征和地面故障数据的数量和质量是无与伦比的。 因此，他们提供了一个独特的机会，推进液化工程的知识和实践。 对基督城的难处理粉质砂进行了取样和先进的循环试验，以表征其循环阻力。 这项工作使全面的文件有见地的情况下，历史的建筑物性能在网站经历不同程度的地震引起的地面故障。 全非线性有效应力反分析的情况下，历史评估的重要性，土-结构相互作用的影响，建筑物在液化场地。 此外，一个液化推广网站将把液化带进教室。从设计级地震中学习对于推进地震专业是非常宝贵的。液化效应的研究在美国是至关重要的，在那里发生的大规模液化发生在基督城可以从字面上摧毁一个城市。 基督城液化危害和基础设施与美国的相似性意味着研究结果将直接转移到美国规模相当的城市，并可扩展到更大的城市中心。 2010-2011年的坎特伯雷地震序列提供了一个机会，在一定程度上的细节和复杂性，不能在美国进行的建筑物块的综合研究。 重要的是，这项研究的重点是液化对结构的影响，而不是现象本身，从而推进了液化工程的实践。 该项目支持新西兰和美国地震研究人员之间的持续国际合作，并允许美国博士学位。学生在新西兰建立研究联系。