Simulation of shear and one-dimensional compression behavior of naturally deposited clays by super/subloading yield surface Cam-clay model
Simulation of shear and one-dimensional compression behavior of naturally deposited clays by super/subloading yield surface Cam-clay model
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DOI：
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发表时间：
2005
影响因子：
3.7
通讯作者：
M. Nakano;K. Nakai;T. Noda;A. Asaoka
中科院分区：
文献类型：
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作者：
M. Nakano;K. Nakai;T. Noda;A. Asaoka
天然沉积粘土具有不同于重塑粘土的复杂力学行为。例如，正常固结状态下的粘土在不排水剪切试验中通常表现出软化，或在严重超固结状态下表现出重绕。超级/次加载屈服面凸轮粘土模型（Asaoka等人，1998年，2000年，2002年），试图澄清复杂的力学行为，在自然沉积的粘土。该模型将结构性、超固结和各向异性的概念及其演化规律引入到修正剑桥模型中。对两种天然沉积原状粘土（更新世粘土和全新世粘土）进行了不排水三轴压缩试验和固结仪试验，并采用超/次加载屈服面剑桥模型进行了模拟。本研究的结果如下：1）对于两种类型的原状粘土，超/次加载屈服面凸轮粘土模型可以模拟从正常固结状态到超固结状态的不排水三轴压缩行为，对应于各种各向同性压力使用一组材料常数。2)此外，该模型可以模拟一维压缩行为使用相同的材料常数用于模拟的不排水三轴压缩行为。3)通过模拟，可以用不同的演化参数以及弹塑性参数来描述具有不同加载历史和经历不同老化效应的更新世粘土和全新世粘土的力学行为。
Naturally deposited clays exhibit complicated mechanical behavior that differs from that of remolded clays. For example, clay in a normally consolidated state commonly exhibits softening in undrained shear tests or rewinding in a heavily overconsolidated state. The Super/subloading Yield Surface Cam-clay model (Asaoka et al., 1998, 2000, 2002) was proposed in an attempt to clarify the complicated mechanical behavior in naturally deposited clays. In this constitutive model, the concepts of structure, overconsolidation, anisotropy, and their evolution laws, are introduced into the modified Cam-clay model. In the present study, undrained triaxial compression tests and oedometer tests were carried out on two types of naturally deposited undisturbed clay, Pleistocene clay and Holocene clay, and the behavior was then simulated using the Super/subloading Yield Surface Cam-clay model. The findings of the present study are as follows: 1) For the two types of undisturbed clay, the Super/subloading Yield Surface Cam-clay model can simulate undrained triaxial compression behavior ranging from the normally consolidated state to the overconsolidated state, corresponding to various isotropic pressures using a single set of material constants. 2) In addition, the model can simulate one-dimensional compression behavior using the same material constants as those used for the simulation of the undrained triaxial compression behavior. 3) Through the simulation, the mechanical behavior of Pleistocene clay and Holocene clay, which have different loading histories and have undergone different aging effects, can be described by the different evolution parameters, as well as the elasto-plastic parameters.