层状岩体抗剪强度产状效应的数值试验研究

Numerical study on occurrence effect of shear strength of stratified rock mass

层状岩体力学特性呈现出明显的各向异性特点,其强度和变形参数不但与作用力和岩体结构面之间的夹角有关,同时还与岩体结构面的走向密切相关。为研究岩体结构面产状对层状岩体抗剪强度参数的取值影响,首先对某工程现场直剪试验进行模型辨识研究,然后采用数值试验方法对层状岩体抗剪断试验进行拓展性数值研究,进而对岩体的抗剪断强度各向异性进行了深入研究,分析了层状岩体抗剪断强度特性与结构面产状之间的变化规律。研究结果表明:层状岩体的抗剪强度参数呈现明显的非正交各向异性特点;随着结构面倾角的增大,抗剪断强度参数与结构面产状之间关系可采用空间椭圆面来描述。

Stratified rock mass has obvious anisotropic mechanical characteristics. The strength and deformation parameters of stratified rock mass are related to the angle between load and structural plane and the strike of structural plane. To explore the influence of rock occurrence on the shear strength parameters, the model identification study on in - situ direct shear test for a project is conducted, and further the shear parameters of stratified rock mass are studied numerically in an extended level. The relationship of shear strength characteristics and occurrence of the plane is analyzed. It indicates that the shear strength parameters of stratified rock mass show an obvious non - orthogonal anisotropic effect; with increase of dip angle of structural plane, the variation law of shear strength parameters and occurrence of structural plane could be described by a spatial ellipse surface.