层状盐岩体的三维Cosserat介质扩展本构模型

Three-dimensional expanded Cosserat medium constitutive model for laminated salt rock

考虑到深部地下岩土工程一般是较复杂的三维问题,在层状盐岩体二维Cosserat介质扩展本构模型基础上,针对不同岩层交替而成的互层盐岩体,建立了宏观平均意义下考虑细观弯曲效应的三维Cosserat介质扩展本构模型,并给出了模型的初步试验验证。该模型既能分析硬(软)夹层对层状盐岩体刚度的强化(弱化)作用,又能考虑由于夹层的存在而导致的层状盐岩构造体宏观意义下力学特性的各向异性,为层状盐岩体及其他层状介质变形和破损分析提供了一种新的思路和方法。该模型可直接推广到非线性问题。结合数值分析软件可进行层状介质体内复杂洞室稳定性分析。

Based on two-dimensional Cosserat constitutive model for layered rockmass, a new three-dimensional expanded Cosserat medium constitutive model, in which the influence of meso bending was taken into account, was proposed for layered salt rock containing two alternate layers with mismatch mechanical properties. It was validated primarily by an experiment on laminated salt rock samples under uniaxial compression. By using this new model, it can be analyzed the influence on stiffness of layered＇salt rock of the presence of hard or soft interlayer and also the macroscopical isotropy of layered salt rock due to interlayer. Combined with conventional strength theories, this model can be utilized further through a routine way for the strength and failure analysis. The proposed model can be expanded to solve nonlinear problems directly, and can be embedded to numerical analytical software for analysis of the stability of complicated underground openings in laminated salt rock.