Effect of Fines Type and Content on Liquefaction Resistance and Ground Failure Potential

细粉类型和含量对抗液化性和接地破坏可能性的影响

• 批准号: 0218365
• 负责人: Charng Juang
• 金额: $ 20.65万
• 依托单位: Clemson University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-10-01 至 2006-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0218365&HistoricalAwards=false
• 关键词: Effect; Fines; Type; Content; Liquefaction

0218365, Charng H. Juang, Clemson University"Effect of Fines Type and Content on Liquefaction Resistance and Ground Failure Potential"The ability to accurately evaluate the liquefaction potential and the liquefaction-induced ground failure potential is important in the engineering planning and design of structures in seismic regions. This research project addresses two important issues in the mitigation of earthquake-induced liquefaction hazards, namely the effect of fines type and content on liquefaction resistance, and the liquefaction-induced ground failure potential. The first topic concerns the triggering of liquefaction, and the second addresses the consequence of liquefaction.With respect to the first topic, recent studies by numerous investigators have concluded that both fines content and fines type affect the liquefaction resistance of soils, but these affects are not fully accounted for in the existing simplified design methods. Data from recent earthquakes offers a rare opportunity to investigate these effects and to improve on the current state of the art on liquefaction triggering analysis.The second topic is more challenging, as reflected in the fact that no readily applicable site-specific model is currently available for evaluating liquefaction-induced ground failure potential. However, the number of case histories from recent earthquakes is now sufficient to establish empirical models for estimating site-specific ground failure potential. This project is collecting this additional case history data on liquefaction triggering and ground failure. This case history data, together with the existing databases, is used to improve the current state of the art on liquefaction triggering analysis, and to develop new empirical models for evaluating liquefaction-induced ground failure potential. Advanced data analysis techniques, including logistic regression analysis, mapping function approach based on artificial neural network, and Bayesian updating technique, are examined and utilized for developing the empirical models.Both deterministic and probabilistic models are being developed. Since the geotechnical engineering profession prefers the deterministic approach, the deterministic models will be developed, but equipped with suggested guidelines including risk-calibrated factor of safety. The probabilistic models are being developed for use in performance-based earthquake engineering, as well as for mapping liquefaction-induced ground failure.

0218365，Chang H. Juang，克莱姆森大学“细粒类型和含量对抗液化性和地面破坏潜力的影响“在地震区的工程规划和结构设计中，准确评估液化潜力和液化引起的地面破坏潜力的能力是重要的。 该研究项目解决了两个重要的问题，在减轻地震引起的液化危害，即粉的类型和含量对抗液化性的影响，和液化引起的地面破坏的潜力。 第一个主题是关于液化的触发，第二个主题是关于液化的后果，关于第一个主题，许多研究人员最近的研究得出结论，细粒含量和细粒类型都会影响土的抗液化性，但这些影响在现有的简化设计方法中没有完全考虑。 最近的地震数据提供了一个难得的机会来调查这些影响，并提高液化触发分析的最新技术水平。第二个主题更具挑战性，反映在这样一个事实，即目前没有现成的适用于特定地点的模型可用于评估液化引起的地面破坏的潜力。 然而，从最近的地震的案例历史的数量，现在足以建立经验模型，估计特定网站的地面故障的潜力。 该项目正在收集有关液化触发和地面破坏的额外案例历史数据。 这种情况下的历史数据，连同现有的数据库，是用来改善目前的液化触发分析的最先进的状态，并开发新的经验模型，用于评估液化引起的地面故障的可能性。 先进的数据分析技术，包括逻辑回归分析，基于人工神经网络的映射函数方法，和贝叶斯更新技术，被检查和用于开发经验模型。确定性和概率模型正在开发中。 由于岩土工程专业更喜欢确定性方法，因此将开发确定性模型，但配备建议的指南，包括风险校准安全系数。 正在开发的概率模型用于基于性能的地震工程，以及映射地震引起的地面故障。