层面倾角对组合岩体破坏失稳的力学特性影响研究

Study on the Influence of Bedding Angle on the Mechanical Properties of Failure and Instability of Composite Rock Mass

具有层面倾角的组合岩体具有明显的倾角效应,其力学性质会随着层面倾角大小的变化而改变。为了探究层面倾角对组合岩体破坏失稳的力学特性影响,通过理论分析和室内实验相结合的方法,得到了单轴压缩下不同层面倾角岩石试样的RA值、应力-应变曲线、峰值强度以及弹性模量。结果表明:不同层面倾角组合岩体在加载初期主要发生剪切破坏,加载到后期贯通扩展为拉伸破坏;倾角15°试样主要发生剪切拉伸复合破坏,倾角25°试样主要发生剪切滑移破坏;峰值强度和弹性模量都随着层面倾角的逐渐增大而减小。

The composite rock mass with bedding angle has obvious dip angle effect,and its mechanical properties will change with the change of bedding angle.In order to explore the influence of bedding angle on the mechanical properties of composite rock mass failure and instability,the RA value,stress-strain curve,peak strength and elastic modulus of rock samples with different bedding angles under uniaxial compression were obtained by theoretical analysis and laboratory test.The results show that the combined rock mass with different bedding angles mainly undergoes shear failure at the initial stage of loading,and then extends to tensile failure at the later stage of loading.The specimen with an inclination angle of 15°mainly undergoes shear tensile composite failure,and the specimen with an inclination angle of 25°mainly undergoes shear slip failure.The peak strength and elastic modulus decrease with the increase of the bedding angle.