考虑围压和密度的饱和砂土液化后单调加载本构方程

Monotonic loading constitutive model of saturated liquefied sand considering the density and confining stress

为评价地震液化时饱和砂土初始液化后变形,研究了有效围压和密度对饱和砂土液化后单调加载应力应变的影响。基于初始液化后加载试验结果,改进了模拟饱和砂土液化后单调加载的本构方程,考虑了围压和密度的影响,并给出了门槛剪切应变随围压变化的关系式。结果表明:密度的影响可以由临界应力状态线的斜率的变化来体现;有效围压变化的影响可以由门槛剪切应变的变化来反映。

The effects of the post-liquefaction saturated sand density and the effective confining stress on the stress and strain for monotonic loading were investigated to evaluate the deformation of liquefied sand during earthquakes. The entrance shear strain is related to the confining stress for saturated liquefied sand. The constitutive loading model was modified to account for the density and confining stress based on the results of the initial liquefied sand loading tests. The results show that the density influences the slope of the critical stress state line while the confining stress influences the entrance shear strain.