含砂高液限黏土统计损伤硬化模型研究

Study of statistical damage hardening model of arenaceous high liquid limit clay

目前,将统计损伤理论应用于岩土体本构模型中尚处于起步阶段。通过对含砂高液限黏土进行常规物理试验和固结排水三轴试验,得到了不同围压下土体的轴向应力应变和体积应变轴向应变曲线,基于损伤理论并假设土体微元服从威布尔分布,建立了统计损伤硬化本构模型。通过将理论结果与试验曲线进行比较,验证了模型的合理性及对硬化型土体应力应变关系的适用性。在此基础上,对模型参数与应力应变曲线、损伤应变曲线之间的关系进行探讨,相关结论对含砂高液限黏土的研究与工程实践具有较好的参考价值。

At present, the application of statistical damage theory in soil constitutive model is still in an initial stage. Through conventional physical and drained triaxial consolidation tests on arenaceous high liquid limit clay, the axial stress - strain curves and volumetric strain - axial strain curves under different confining pressures are obtained. Based on the damage theory and as- sumption that the micro - unit of the soil obeys Weibull distribution, a statistical damage constitutive model is established. By comparing the computational results with test results, the rationality of the new model and its applicability to the stress - strain re- lation of hardening soil are proved. On this basis, the relationship of Weibull distribution parameters with stress - strain curves and damage - strain curves are discussed, the results would provide reference for the engineering application in arenaceous high liquid limit clay area.