变围压-孔压条件下含气煤岩应力应变关系研究  

Study on the Stress-Strain Relationship of Gas-Bearing Coal Rock Under Variable Confining Pressure-Pore Pressure Conditions

作　　者：房平亮[1,2] 邵黎明[1] 曾志国[3] 李宁[1] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国地质大学(北京)能源学院,北京100083 [3]华北油田公司采油工程研究院,河北任丘062552

出　　处：《应用数学和力学》2014年第7期768-776,共9页Applied Mathematics and Mechanics

基　　金：国家高技术研究发展计划(863计划)项目(2013AA064902)~~

摘　　要：为研究围压及孔压对含气煤岩本构关系的影响,基于弹性力学及破坏理论,建立了细观非均匀弹脆性模型,利用FEPG数值模拟软件,编制了有限元计算程序,用数值方法模拟了含气煤岩体在变围压-孔压条件下的变形及破坏规律.结果表明,围压增大时,煤岩体由脆性逐渐转呈柔性,且承载能力有所增强,而孔压的影响则恰好相反.将数值模拟结果分别与变围压、变孔压实验数据进行了对比,两者基本相符,充分验证了力学模型的适用性及计算程序的正确性.Under different confining pressure-pore pressure conditions, the numerical method was used to simulate the failure process and the stress-strain relationship of gas-bearing coal rock. A micro-heterogeneous elastic-brittle model based on elasticity theory and failure theory was constructed with the influences of confining pressure and pore pressure considered. An FEM program was developed partially out of the FEPG software, to simulate the deformation and failure behaviors of the gas-bearing coal rock under variable confining pressure-pore pres- sure conditions. The results show that the coal rock becomes ductile with increase of the confi- ning pressure, and the carrying capacity is enhanced, while the influence of the pore pressure is just opposite. The simulation results quantitatively agree well with the experimental results, which, to a certain extent, proves accuracy of the proposed constitutional model and effective- ness of the FEM program.

关 键 词：围压 孔压 细观非均匀性 弹脆性模型 应力应变关系 脆性 柔性 

分 类 号：O39[理学—工程力学]