CAREER: A Direct In Situ Approach for Evaluating Liquefaction Characteristics of Soil Deposits

这项职业研究涉及开发可以直接评估地表5至10米范围内近地表沉积物液化特征的现场技术。利用这些技术可以更准确和可靠地确定液化势，并将通过各种现场调查来提高对液化的认识。将进行的研究需要开发一种液化评估试验，该试验在现场动态加载土体，同时测量诱导应变和超孔隙水压力。与现有的基于经验的液化评估技术相比，这种测试技术将提供更多关于土壤沉积物的液化势和孔压产生特性的信息。在诱发震动过程中和之后，将使用埋入式孔压传感器研究孔压的产生、迁移和消散。来自现场的孔压传感器的数据，以及对孔压产生现象的数值模拟，将提供各种孔压产生模型的验证。这种现场测试技术可以更准确地评估土壤沉积物的液化特性和液化势，现场评估土壤沉积物的孔压产生特性，并提高对液化的认识。作为这个项目的一个组成部分，工程专业的学生将通过在课堂上使用工程案例来准备技术和非技术问题。工程案例是对真实工程项目的书面描述。阅读和讨论本科生和研究生水平的工程课程中的相关案例可以更好地为学生的工程生涯做好准备。

This Career research involves developing in situ techniques that can directly assess the liquefaction characteristics of near surface deposits, within 5 to 10 meters of the ground surface. More accurate and reliable determinations of liquefaction potential will be possible with these techniques and the state of knowledge regarding liquefaction will be advanced through various site investigations.The research to be undertaken entails developing a liquefaction evaluation test that dynamically loads the soil in situ while measuring the induced strains and excess pore water pressures. This testing technique will provide significantly more information regarding the liquefaction potential and pore pressure generation characteristics of a soil deposit than in currently possible with available empirically based liquefaction evaluation techniques. Pore water pressure generation, migration, and dissipation during and after the induced shaking will be studied with embedded pore pressure transducers. Data from pore pressure transducers in the field, along with numerical modeling of the pore pressure generation phenomena, will provide validation of various pore pressure generation models. This is situ testing technique will allow the liquefaction characteristics and liquefaction potential of soil deposits to be assessed more accurately, the pore pressure generation characteristics of soil deposits to be evaluated in situ, and the state of knowledge regarding liquefaction to be advanced.As an integral part of this project, engineering students will be prepared for both technical and non-technical issues through the use of engineering cases in class-rooms. An engineering case is a written account of a real engineering project. Reading and discussing relevant cases in both undergraduate and graduate level engineering courses can better prepare students for engineering careers.