基于广义塑性力学的Cam-clay模型的改进

针对Cam-clay模型计算中存在没有充分考虑剪切变形的缺点,首先采用理论分析的手段,指出产生此现象的原因,同时提出由剪应力和体应力引起的应变分量分别采用不同的分配比例系数的思想。在此基础上采用南京水利科学院的剪切试验对Cam-clay模型进行改进,给出了基于不同分配比例系数的、改进后的Cam-clay模型的应力与应变关系的计算式,最终得到改进了的Cam-clay模型含有4个独立的试验参数。通过算例对改进后的模型与Cam-clay模型进行比较,揭示了改进后的模型能够有效地考虑剪切变形。

Improvement of Cam-clay Model Based on Generalized Plastic Mechanics

The defect of Cam-clay model that shear deformation is not considered sufficiently is theoretically analyzed. The idea of adopting two proportional coefficients to strain components induced respectively by shear stress and volume stress is proposed. Based on this idea and using the test performed by Nanjing Hydraulic research institute, the Cam-clay model is modified. The stress-strain relation in the modified model includes four material parameters within which three parameters are the same as Cam-clay model's and the additional one is shear modulus. The computed results obtained by using the two models showed that the shear deformation can be considered effectively in improved Cam-clay model.