Soil Liquefaction Hazard Assessment by the Vision Cone Penetrometer

这项研究计划使用新开发的视锥渗透仪(VisCPT)来评估地震引起的液化危险。VisCPT本质上是一种标准的电子锥体贯入仪，通过包括两个微型CCD摄像机进行了改进。摄像机通过两个级别的放大收集土壤地层的连续视频图像。VisCPT可以描绘土壤地层，并通过各种计算机视觉技术提供土壤的粒度分析。该项目的目标是在旧金山金银岛的国家土工试验场(NGES)收集细粒百分比不同的位置的VisCPT数据。还采集了物理土壤样本。对收集的VisCPT数据进行了评估，特别关注用于确定粒度分布的图像纹理技术。还将VisCPT图像与标准CPT尖端电阻测量结果进行比较，以说明和量化地层分层和界面对CPT读数的影响。

This research program addresses the use of a newly developed Vision Cone Penetrometer (VisCPT) for earthquake-induced liquefaction hazard assessment. The VisCPT is essentially a standard electronic cone penetrometer, modified by inclusion of two miniature CCD video cameras. The cameras collect a continuous stream of video images of the soil stratigraphy by two levels of magnification. The VisCPT can delineate soil stratigraphy, and through various computer vision techniques, provide a grain size analysis of the soil.The objective of this project is to collect VisCPT date at the National Geotechnical Experimentation Site (NGES) on Treasure Island in San Francisco, at locations with variable percentages of fine particles. Physical soil samples are also taken. The collected VisCPT data is evaluated with specific focus on image-texture techniques for determining grain size distributions. The VisCPT images are also compared to standard CPT tip resistance measurements in order to illustrate and quantify the effects of stratigraphic layering and interfaces on CPT readings.