片状岩石全应力应变压缩过程及力学机制试验研究

Complete Stress-strain Process and Mechanical Mechanism of Lamellar Rock under Compression Condition

为了解片状岩石的全应力应变压缩过程及力学机制,利用RMT-150C岩石力学刚性伺服试验系统,对绿泥石片岩和云母石英片岩进行压缩力学试验.基于试验结果,得到岩石全应力应变压缩过程,提出峰前压密、线弹性、微裂隙稳态扩展和微裂隙不稳态扩展4个变形阶段以及峰后应变软化、残余应力稳定两个变形阶段,分析岩石在各阶段的强度变形特性以及体应变、横向应变和轴向应变之间的关系;详细探讨压缩条件下水对试样物理力学性质的影响规律,重点对比峰值强度、弹性(变形)模量等指标的敏感程度和围压效应;并揭示片状岩石在压缩状态下的破裂模式,将整个破坏过程分为单一剪切破裂、鼓状破裂、Y字形破裂及平行劈裂4种形式.

To understand complete stress-strain process and mechanical mechanism of chlorite schist and sericite schist under compression condition,compression experiment was made by RMT-150C rock mechanics test system.Based on the experimental results,pre-peak four phases and post-peak tow phases of the complete stress-strain curve were analyzed;strength and deformation characteristics of rock on every phase were studied,including volume strain,transverse strain and axial strain.Effect law of water on mechanical properties of rock was discussed;and confining pressure effect or sensitivity on strength and deformation parameters,including peak strength,elastic modulus and deformation modulus,was compared.At last,the failure modes of lamellar rock under compression condition were revealed.The whole failure process was divided into four patterns,including single shear failure,drum failure,Y-shape failure and parallel split.