煤层瓦斯抽采过程中煤岩变形的物理模拟实验

利用自主研发的多场耦合煤层瓦斯抽采物理模拟实验系统，研究了抽采过程中煤体内不同位置变形演化规律，探讨了抽采位置、地应力和气体压力对抽采过程中煤体变形的影响。结果表明：煤体变形受地应力、抽采位置、时间和煤层气体压力等因素的共同影响，且抽采初期的煤体变形速率较大；煤体σ1方向的变形普遍大于σ2和σ3方向的变形，σ3方向的变形与煤体所受的地应力大小σ3呈正比；由于最先产生变形的煤体引起的泊松效应限制了距离抽采位置较远煤体的变形量，所以距离抽采位置越近，抽采过程中煤体变形速率和最终变形量越大；煤层中的气体压力越大，煤体变形速率越快，在气体压力降低并趋于稳定后，煤体变形达到一个稳定状态。

Physical simulation of coal and rock deformation in the process of coal seam gas extraction

A physical simulation system of multi-fields coupled was developed for simulating coal deformation in different locations of coal during the gas extraction.In particularly，extraction position，geo-stress，and gas pressure on the deformation of coal was investigated.The research results demonstrate that：① Coal deformation is affected by the coupled factors of ground stress，extraction location，gas pressure，and time；② Coal deformation of σ1-direction is more than that of σ2 and σ3 directions，and the deformation of σ3-direction is proportional to the geo-stress；③ Area around extraction borehole produces high coal deformation rate during extraction；④ The high gas pressure in the coal seams induces coal body deformation fast while low gas pressure causes a steady state coal deformation.