含卸压孔煤岩蠕变特性研究

Study on Creep Characteristics of Coal Rock wth Pressure Relief Hole

为了研究含卸压孔煤岩蠕变特性,开展了单轴压缩条件下完整煤岩与含卸压孔煤岩在不同应力水平条件下的蠕变试验。试验结果表明:同级应力水平下,煤岩蠕变经历了瞬时弹性变形、减速蠕变、等速蠕变和加速蠕变的演化阶段;含卸压孔煤岩的瞬时应变和蠕变量比完整试样更大;且基于FLAC3D的数值模拟结果与实际试验结果十分相似,说明所采用的Burgers模型能够较好地反映煤岩蠕变物理力学性能。研究结果对含卸压孔煤岩体长期强度分析及冲击地压解危具有较好的理论指导意义。

In order to study the creep characteristics of coal rock with pressure relief holes, the creep tests on intact coal rock and coal rock with pressure relief holes under uniaxial compression were carried out under different stress levels. The test results show that under the same stress level, the creep of coal rock has experienced the evolution stages of instantaneous elastic deformation, deceleration creep, constant creep and accelerated creep. The instantaneous strain and creep amount of coal rock with pressure relief holes are larger than those of intact samples. The numerical simulation results based on FLAC3D are very similar to the actual test results, indicating that the Burgers model can better reflect the physical and mechanical properties of coal rock creep. The research results have a good theoretical guiding significance for the long-term strength analysis of coal rock mass with pressure relief holes and the solution of rock burst.