层状盐岩体非线性蠕变本构模型

 针对由不同岩层交替而组成的层状盐岩体，建立泥岩夹层和盐岩复合体代表单元，根据应变协调原理，从细观力学分析角度通过考虑泥岩夹层弹性性质、盐岩弹性及蠕变力学特性以及两相体积含量建立层状盐岩体宏观各向异性非线性蠕变增量型本构模型，分析层状盐岩在蠕变过程中因保持细观应变协调而产生的应力重分布问题，给出新本构模型ABAQUS有限元二次开发增量迭代算法实现方法，对一层状盐岩体简单试样算例进行初步计算分析验证，分析计算与试验结果吻合较好，表明该本构模型能反映细观应变协调时层状盐岩体宏观蠕变力学特性，该模型将为层状盐岩体内硐室长期稳定性分析提供理论计算基础。

NONLINEAR CREEP CONSTITUTIVE MODEL OF BEDDED SALT ROCK

As for alternating layers of mudstone and salt rock，representative volume element(RVE) in the composite is established. Based on strain compatibility principle and micromechanical method，considering elastic behavior of mudstone interbeds，elastic and creep behavior of salt，an anisotropic incremental nonlinear composite creep constitutive model of bedded salt rock is derived；stress redistribution is analyzed during creep deformation of salt. The new model is introduced into finite element software ABAQUS. A simple bedded salt rock sample is modeled as case study to verify the composite model. The result agrees well with the experiment，so it is shown that the constitutive model can reflect mechanical behavior of bedded salt rock considering micro-strain compatibility. The model can be employed to analyze long-term stability of bedded salt rock cavern in the future.