岩石破裂行为的实验研究

岩样的破裂行为、破坏过程和参数测试是裂隙断裂构造研究的基础和依据。实验岩石样品采自四川东部和新疆北部地区，为测试准确起见，对岩样进行了应力等值线的有限元法计算。通过单轴和三轴实验的岩样破坏观察和应力应变曲线对比，将岩石的破裂行为、应力应变划分为四个阶段，即裂隙压密阶段、弹性变形阶段、微观劈裂阶段和宏观破裂阶段。基于单轴抗压实验岩石劈裂—破裂—碎裂发展过程的微观分析，可以看出宏观破裂主要是沿岩样原有的隐裂隙、临界裂隙发育的，许多新裂隙则主要是在宏观破裂阶段产生的。

Experiment on the Fracture Behaviour in Rocks

Fracture behaviour,failure process and parameter determination of the rock specimens are the basis for research on the fissure fault structures. Experimental rock specimens were collected from the eastern Sichuan and northern Xinjiang provinces,and the stress isopleths to the rock specimens were calculated with a finite element method (FEM) for accurate determination. Based on the failure observation and curve comparison of rock specimens from the uniaxial and triaxial experiments,the fracture behaviour and stress-strain of the rocks can be divided into four stages,the fissure pressure-airtightness stage,the elastic deformation stage,the microscopic split stage and the macroscopic fracture stage. Through the microscopic analysis of developing process of the rock split-fracture-smash from the uniaxial pressure experiment,it is found that the macroscopic fractures are mainly developed along the primitive hidden fissures and critical fissures,and formation of many new fissures mainly occurs in the macroscopic fracture stage.