黏土结构性参数测定研究

Study on parameter determination of structured clays

对人工制备结构性黏土进行了5种贯入速率下的室内孔压静力触探试验(CPTU)。把结构性黏土的流变分为滑移流变和损伤流变,在沈珠江堆砌体模型的基础上,采用过应力理论,建立结构性黏土流变模型。引入一个接触面模型,编制大变形固结程序并采用所建立的流变模型模拟结构性黏土室内孔压静力触探试验,验证了程序和模型的正确性。利用该程序模拟不同门槛损伤力q0的孔压静力触探,反演出该参数的原位测试公式。

Piezo cone penetration tests （CPTU） on structured soils at different installation rates were carried out. Based on the masonry model proposed by SHEN Zhu-jiang, a viscous-elastic-plastic model for structured clays was proposed by adopting the overstress theory. It was assumed that the total viscous deformation was composed of sliding viscous deformation and damage viscous deformation. On the basis of nonlinear continuum mechanics, the total Lagrange method was used to develop an FEM consolidation analysis program for large-strain analysis. The CPTU tests were successfully simulated by the FEM program and the constitutive model. The parameter q0 was derived from the CPTU simulations with inversion method.