基于位移反演分析的小煤柱损伤渗透特性研究

Research on Permeability Characteristics of Small Coal Pillar Damage Based on Displacement Back Analysis

某矿8204工作面回风巷采用小煤柱护巷布置方式,为分析小煤柱破坏损伤程度及煤层透气性,基于ABAQUS数值模拟,从研究开采扰动引起的裂隙带空间结构、覆岩应力场分布特征出发,分析掘巷期间、回采期间小煤柱应力状态、损伤应变及透气性的时空分布规律。模拟结果表明,掘进工作面附近的煤柱透气性系数急剧增长,随着向前或向后远离掘进工作面,透气性系数迅速衰减;工作面后方煤柱破坏严重,与掘进时期相比,煤柱透气性系数大大增加,局部增加2个数量级以上。

The return airway of 8204 working face in a mine uses the layout way of small coal pillar protecting roadway. In order to analyze small coal pillar damage degree and coal seam permeability, based on ABAQUS numerical simulation, from the study of mining disturbance caused by fracture zone space structure, overlying strata stress field distribution characteristics, the paper analyzes small coal pillar stress state, damage strain and temporal and spatial distribution of permeability during tunneling and mining period. The simulation results show that the coal pillar permeability coefficient near tunneling working face rapidly increases; permeability coefficient rapidly decreases as the coal pillar is forward or backward away from the tunneling working surface; the coal pillar failure behind working face is serious, and comparing with the tunneling period, the permeability of coal pillar coefficient increases greatly, and the local increase is more than two orders of magnitude.