SOIL-WATER COUPLED BEHAVIOUR OF SATURATED CLAY NEAR/AT CRITICAL STATE
SOIL-WATER COUPLED BEHAVIOUR OF SATURATED CLAY NEAR/AT CRITICAL STATE
复制标题
饱和粘土接近/临界状态下的土水耦合行为
DOI：
10.3208/sandf1972.34.91
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发表时间：
1994
影响因子：
3.7
通讯作者：
T. Noda
中科院分区：
文献类型：
--
作者：
A. Asaoka;M. Nakano;T. Noda
采用Cam-Clay本构模型进行土-水耦合有限变形分析，模拟不排水三轴压缩试验，以研究临界状态附近/临界状态下粘土的性状。为了补充分析结果，还进行了一系列饱和重塑粘土的试验。通过试验和数值分析，得到以下结论：（1）考虑加载准则，通过对临界状态下塑性乘数的研究，发现粘土达到临界状态后可能出现三种加载方式，即软化、仍停留在临界状态和硬化。(2)基于Cam-Clay土水耦合计算，在刚性-粗糙集和不排水边界条件下的三轴压缩试验中，单个土样会出现硬化、软化和卸荷区域，从而自然地产生关于比容和超静孔压的高度不均匀状态。这种不均匀性也是由于在“不排水”试验期间孔隙水的迁移而发现的。(3)粘土破坏后的不排水强度的“建立”也可以在剑桥的框架内得到非常自然的解释。这是因为剑桥模型详细描述了粘土破坏后的状态。因此，以破坏状态为初始条件，土-水耦合变形分析很容易解决粘土在给定荷载条件下的“立起”问题。通过室内三轴试验解决重塑粘土的“摆台”试验，说明了该方法的可行性。（一）
Soil-water coupled finite deformation analysis using the Cam-Clay constitutive model was newly applied for the simulation of undrained triaxial compression test in order to investigate the behaviour of clay near/at the critical state. A series of experiments on saturated remoulded clay was also carried out to supplement the results of analyses. Through experiment and numerical analyses, the following findings are obtained: (1) Considering the loading criterion, and investigating the plastic multiplier at the critical state, three types of loading are found possible for the clay after reaching the critical state, that is, softening, still staying at the critical state, and hardening. (2) Based on the soil-water coupled Cam-Clay computation, the triaxial compression test with rigid-rough pedestals and with undrained boundaries develops hardening, softening and unloading regions in a single soil specimen, which naturally yields highly inhomogeneous state with respect to both specific volume and excess pore pressure. This inhomogeneity is also found due to migration of pore water during "undrained" testing. (3) The "set-up" of undrained strength of clay after failure can also be interpreted very naturally within the framework of Cam-Clay. This is because the Cam-Clay model describes the state of clay after failure in details. Therefore, taking the failure state as an initial condition, the soil-water coupled deformation analysis easily solves the "set-up" problem of clay under given loading condition. The feasibility of which is illustrated through solving the "set-up" experiment of remoulded clay by means of laboratory triaxial testing. (A)