Research On The Mechanical Properties Of Irregular Rock Fracture With Filled Joint

To research the macro and micro fracture mechanism of three-dimensional irregular jointed sandstone,explore the variation law of mechanical parameters,fracture characteristics and energy evolution of sandstone with joint conditions under different loading conditions.The main conclusions are as follows:(1)The mechanical parameters of similar materials with different ratios were obtained.The quartz sand,lime and gypsum were selected to simulate the sandstone according to the mass ratio of 4: 0.7: 0.3,and the water-gypsum ratio was 0.6 to simulate the joint.The stress-strain,compressive strength,fracture characteristics and energy evolution of three-dimensional irregular sandstone with different joint penetration were systematically studied.(2)The finite element numerical model of sandstone with different dip angles is established and the uniaxial compression test is carried out.The influence of the stressstrain,compressive strength and anisotropy of three-dimensional irregular sandstone is systematically discussed.The evolution of stress concentration zone,acoustic emission signal,crack propagation and fracture evolution are analyzed.(3)The mechanical parameters,deformation and failure of specimens are studied.The reasons for the failure and instability of irregular sandstone particles under unconstrained radial load are analyzed from the energy point of view,and the mechanical properties of sandstone particles under different load conditions are discussed.(4)RFPA3D was used to simulate the mesoscale fracture process of specimens under different loading conditions and compared with physical experiments.The evolution characteristics of surface stress field and displacement field,crack propagation and fracture evolution were analyzed.