Measurement of Liquefaction Ground Failure Resulting from the 1989 Loma Prieta Earthquake

该项目是NSF/USGS的一部分。 国家地震局的倡议 减少危害计划（NEHRP）， 调查洛马普列塔的影响 1989年10月17日地震。 这次地震导致液化发生 在旧金山弗朗西斯科海湾地区的许多地方。 液化是一种非常有害的土壤形式 失败，造成相当大的损害， 1906年的弗朗西斯科和1989年的洛马 普列塔地震。 的当前技术 确定抗液化强度 土壤存款利用间接方法， 关联土壤渗透阻力 剪切波速度与液化 潜力 这项研究计划的目的是 研究一种替代技术， 更直接地衡量 土壤存款，即通过 直接在现场测量的变化， 受剪孔隙压力 株 这是通过使用剪切来实现的 叶片。CSU（科罗拉多州立大学） Piezovane测量瞬时变化 快速旋转时的孔隙压力 叶片。 这项研究计划的目的是 应用CSU Piezovane识别 易液化的材料， 进行系统的研究 对旧金山弗朗西斯科遗址的调查 在洛马河期间液化的海湾地区 普列塔地震。 预计这一 信息将大大增加 全面的岩土工程勘察， 收集类似的数据， 自从洛马普列塔地震以来

This project is part of the NSF/USGS initiative within the National Earthquake Hazard Reduction Program (NEHRP) to investigate the effects of the Loma Prieta earthquake of 17 October 1989. This earthquake caused liquefaction to occur at many sites in the San Francisco Bay area. Liquefaction, a very damaging form of soil failure, caused considerable damage during both the 1906 San Francisco and the 1989 Loma Prieta earthquakes. Current techniques for determining the liquefaction resistance of a soil deposit utilize an indirect method by correlating the soil penetration resistance and shear wave velocity with the liquefaction potential. The purpose of this research program is to study an alternative technique which gives a more direct measure of the potential for a soil deposit to liquefy, namely through a direct in-situ measurement of the change in soil pore pressure when subjected to shear strain. This is achieved by using a shear vane. This CSU (Colorado State University) Piezovane measures instantaneous changes in pore pressure during rapid rotation of the vane. The objective of this research program is to apply the CSU Piezovane to identify the material susceptible to liquefaction, by conducting a systematic research investigation of sites in the San Francisco Bay area that liquefied during the Loma Prieta earthquake. It is expected that this information will add significantly to the comprehensive geotechnical investigations to gather similar data that have been performed since the Loma Prieta earthquake.