Liquefaction Hazard

液化是结构性地震的主要原因 地震时的损坏。（液化是一种 在强剪切过程中土壤抗剪强度的损失 地动山摇）。 公认的评估程序 液化危险是“简化的 液化评价方法 “潜力”是Seed和Idriss提出的。 最近的观察表明， 程序可能会高估液化 里氏地震的危险性 6.5或更少。因为对设计的修改 为了防止液化破坏， 昂贵的，任何高估 液化危害在经济上 不受欢迎。 这项研究计划的目的是 检验这个假设， 在此简化的 程序太小， 地震 这一目标的实现是通过 分析现场性能数据，以及 统计导出震级标度 与观察到的一致的因素 性能 正在处理的任务包括：（1） 岩土工程数据 已经收集到了， （2）在现场或现场附近有记录; 通过钻探来补充这些历史 并测试其他地面地点 运动和过去的液化行为是 已知的，（3）重新分析表中的情况 历史 这项研究计划预计将减少 计算出的危害程度 与观察到的场行为，导致更少 昂贵但同样安全的设计， 建设

Liquefaction is a major cause of structural damage during earthquakes. (Liquefaction is a loss of shear strength of soils during strong ground shaking). The accepted procedure for assessing liquefaction hazard is the "simplified procedure for evaluating liquefaction potential" developed by Seed and Idriss. Recent observations indicate that this procedure may overestimate the liquefaction hazard for earthquakes of Richter magnitude 6.5 or less. Since modifications to a design to prevent liquefaction damage are usually expensive, any overestimate of the liquefaction hazard is economically undesirable. The objective of this research program is to examine the hypothesis that the magnitude scaling factors used in this simplified procedure are too small for moderate earthquakes. This objective is achieved by analyzing field performance data, and statistically deriving magnitude scaling factors that are consistent with observed performance. The tasks being addressed include, (1) the analysis of sites where geotechnical data have been collected, and where ground motions have been recorded at or near the site; (2) supplementing these few histories by drilling and testing additional sites where ground motions and past liquefaction behavior are known, and (3) reanalyzing tabulated case histories. This research program is expected to reduce the calculated hazards to a level consistent with observed field behavior, leading to less costly though equally safe design and construction.