Verification of Soil Liquefaction Analysis by Coordinated Geotechnical Centrifuge Studies

通过协调岩土离心机研究验证土壤液化分析

• 批准号: 9000390
• 负责人: Ronald Scott
• 金额: $ 25.56万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-12-01 至 1994-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9000390&HistoricalAwards=false
• 关键词: Verification; Soil; Liquefaction; Analysis; Coordinated

Water-saturated sandy soils are susceptible to liquefaction when subjected to strong ground shaking, such as occurs during an earthquake. Liquefied soils experience a decrease in bearing strength: this can lead to the partial or total collapse of buildings standing on liquefied soils. The aim of this project is to verify the analyses used to predict liquefaction due to earthquake loading. Since the field data needed for this verification is extremely difficult to obtain, data is being used instead from laboratory experiments performed on geotechnical centrifuges. This is a relatively new technique for soil testing which is becoming well accepted in the geotechnical research community. The technique for simulating earthquakes on centrifuges is being developed, and the results obtained have generated confidence in the method: questions that remain to be answered are being addressed in this study. Different geotechnical structures, including sloping ground, dams, coastal dikes, and embankments are being investigated so as to validate the applicability of the liquefaction analysis methods to a variety of geotechnical structures. Class A predictions - which involve predicting the soil response without knowing the measured results - are used for later comparison with measured results. The Earth Technology Corporation is responsible for the management of the project, for providing carefully calibrated soil samples, for overseeing the testing program, as well as being responsible for receiving, distributing and documenting data, in conjunction with the Adjudication Committee. It is also responsible for managing the prediction studies. The Adjudication Committee acts as an independent steering group. The participating institutions are the University of California at Davis and Berkeley, the California Institute of Technology, the University of Colorado, the Massachusetts Institute of Technology, Princeton University, and Cambridge University, England. Collectively, they are examining the mechanisms of liquefaction, the development and verification of analytical and numerical models, soil-structure interaction for conditions of limited and large deformations, and the effect of interfaces between soil layers of differing permeabilities. This study will contribute significantly to improving the understanding of the soil liquefaction phenomenon, and to the reliability of methods used to predict the occurrence of liquefaction and the resulting damage to structures. This action is for support of the program at the California Institute of Technology.

当受到强烈的地面摇动时，例如在地震期间发生，水饱和的沙质土壤容易受到液化的影响。 液化土壤的轴承强度降低：这可能导致建筑物站在液化土壤上的部分或完全崩溃。 该项目的目的是验证用于预测地震载荷引起的液化的分析。 由于此验证所需的现场数据非常困难，因此正在使用数据，而是来自对岩土离心机进行的实验室实验。 这是一种用于土壤测试的相对较新的技术，在岩土技术研究所已被广泛接受。 正在开发模拟离心机上的地震的技术，并且获得的结果对该方法产生了信心：在本研究中正在解决待回答的问题。 正在研究不同的岩土结构，包括倾斜地面，大坝，沿海堤防和路堤，以验证液化分析方法对各种岩土技术结构的适用性。 A类预测（涉及预测土壤反应而不知道测量结果）的预测用于以后与测量结果进行比较。 Earth Technology Corporation负责该项目的管理，提供精心校准的土壤样品，以监督测试计划，并负责与裁决委员会结合使用，并负责接收，分发和记录数据。 它还负责管理预测研究。 裁决委员会是一个独立的转向小组。 参与的机构是加利福尼亚大学戴维斯分校和伯克利分校，加利福尼亚理工学院，科罗拉多大学，马萨诸塞大学理工学院，普林斯顿大学和英格兰剑桥大学。 他们总的来说，他们正在研究液化的机制，分析和数值模型的发展和验证，有限和大变形条件的土壤结构相互作用以及不同渗透率的土壤层之间接口的影响。 这项研究将对改善对土壤液化现象的理解以及用于预测液化发生的方法的可靠性以及对结构造成的损害的可靠性产生重大贡献。 此行动是为了支持加利福尼亚理工学院的计划。