不同围压梯度下砂岩力学及声发射特性研究

Study on the Mechanical and Acoustic Emission Characteristics of Sandstone under Gradient Confining Pressures

分别对砂岩试样施加不同围压,在不同围压梯度下,施加轴向荷载,探究应力-应变的变化及声发射产生数量规律;基于离散元理论,采用二维颗粒流PFC2D软件,建立不同围压下砂岩岩石模型,结合试验数据,研究不同围压梯度下砂岩力学特性及声发射事件的产生。结果表明:随着围压的不断增大,砂岩的破坏应力逐渐增大,达到破坏后产生的微裂缝也逐渐增多。

The changes in stress-strain and the quantitative law of acoustic emission are explored by deploying axial loads under different confining pressure gradients to the sandstone samples.Based on the discrete element theory,by the two-dismensional particle flow PFC2D softwar,the model of sandstone rock under different confining pressures are established.The mechanical properties of sandstone under different confining pressure gradients and the generation of acoustic emission events are studied based on the test data.The result shows that as the confining pressure continuously goes up,the failure stress of sandstone gradually increases,with increasing microcracks generated after failure.