Site Characterization and Assessment of In Situ State Properties of Geomaterials

9531782需要准确和快速的实地测试来评估土壤特性和行为，以支持社会对基础设施发展和恢复的持续投资的需要。为满足这一需求，压电锥贯入仪(PCP)成为越来越多的研究工具。这项研究旨在建立各向异性、速率相关的本构模型和任意拉格朗日-欧拉有限元程序(ALE)，以首次预测不同贯入率下的锥体阻力和超孔压。模型的能力将通过最先进的校准室测试进行验证和验证，这些测试将侧重于渗透率、侧向应力系数、超固结比和对圆锥数据的尺度效应。非标准孔压消散曲线的解释是由正常应力降低引起的初始超孔压降引起的，以及它相对于重分布和应力历史效应的初始变化。这项研究将根据PCP试验数据，制定准确的简化方法和图表，以评估工程土参数、地基改良效果和深基础的性能(即桩承载力随时间的增加)。***

9531782 Accurate and speedy field testing to evaluate soil characteristics and behavior is needed to support society's need for continued investment in infrastructure development and rehabilitation. The piezocone penetrometer (PCP) is the increasingly chosen investigation tool to meet this demand. The proposed research aims to develop an anisotropic, rate- dependent constitutive model and an Arbitrary-Lagrangean-Eularean (ALE) finite element code to predict for the first time, cone resistance and excess pore water pressures at various rates of cone penetration. The capability of the model will be verified and validated by state-of-the-art calibration chamber tests that will focus on penetration rate, lateral stress coefficient, overconsolidation ratio, and scale effects on cone data. Interpretation of non-standard pore water pressure dissipation curves arising from initial excess pore pressure drop due to normal stress reduction and its initial variation with respect to redistribution and stress history effects will be investigated. This research will formulate accurate simplified methods and charts to evaluate engineering soil parameters, ground improvement effectiveness, and performance of deep foundations (i.e. increase in pile capacity with time) from PCP test data. ***