饱和软粘土不排水循环加载作用下蠕变特性的研究

为了探讨珠江三角洲的饱和软粘土在交通行车荷载作用下的变形特性，在K0固结状态下进行了一系列不排水的单向循环加载蠕变试验。研究表明：根据循环荷载的大小，饱和软粘土的累积变形可分为衰减型和破坏型；衰减型循环蠕变的累积应变速率与循环次数的关系可用幂函数来表示，引入相对偏应力水平参数，可考虑动偏应力、初始静偏力和围压的综合影响，累积应变速率与相对偏应力水平的关系可用指数函数来表示。基于流动理论，建立了珠江三角洲饱和软粘土的应变速率状态方程，该模型较好地表达了衰减型循环蠕变的应变速率—应力水平—循环次数关系。

Study on cyclic creep behavior of saturated soft clay under undrained condition

In order to study the deformation behaviour of Pearl River Delta saturated soft clay under long-term cyclic loading, a series of undrained cyclic triaxial tests were performed under K0 consolidation. The results of tests show that：(a)Base on the intensity of cyclic loading, the accumulative cyclic strain can be divided into tow types, that is, decrescent cyclic creep and accelerated cyclic creep. (b)In decrescent cyclic creep , power function is adopted for the relationship of cyclic number and accumulative cyclic strain and exponenrial function is adopted for the relationship of relative deviator stress and accumulative cyclic strain. (c) The relative deviatoric stress level was introduced considering the effects of initial static deviatoric stress，cyclic deviatoric stress and confining pressure．Base on the flue theory of creep, the cumulative strain rate equation of Pearl River Delta saturated soft clay was established. the equation can rightly give expression to strain rate-stress-cyclic number relationship.