长壁工作面“T”型交叉口围岩稳定性分析

Analysis on T-Intersections Surrounding Rock Stability at Longwall Mining Face

采用理论分析和数值模拟方法,分析长壁工作面顺槽和开切眼交叉口煤柱、顶板和底板的应力场与位移场分布特征,以确定围岩稳定性状况。研究结果表明:由于受二次应力场叠加的影响,煤柱在交叉口拐角处围岩裂化,形成较大范围的弧形三角形卸压区,此处是煤壁片帮严重、顶板下沉剧烈区和底鼓区集中的地方;交叉口处围岩的强扰动区域半径大约是巷道的宽度;建议在强扰动区域内采用整体锚固方式,加大锚杆、锚索支护的强度、深度和密度,并采用锚网、钢带和钢筋梁等支护构件,必要时利用单体支柱支护顶板。研究结果可以给同类条件下长壁工作面的开采支护提供参考。

Based on the methods of theoretical analysis and 3D numerical simulation,the stress field and displacement distribution characteristics of coal pillar,roof and floor at the T-intersections of longwall working face crossheading and open-off cut were analyzed to study the stability of the surrounding rock.The study showed that the surrounding rock in the corner of the T-intersections cracked and a large ranged arc triangle distressed zone was formed,where there were serious coal wall caving,roof sag and floor heave.The radius of surrounding rock strong disturbed zone was approximately equal to the width of roadway.It is suggested that the integral anchorage should be applied in the strong disturbed zone,strength,depth and density of bolting and anchoring support should be expanded,the supporting structural members of anchored net,anchored steel belt,sprayed concrete and anchorage cable can be applied,and the single hydraulic prop can be used to support the roof if necessary.The results can provide references for support of longwall working faces with similar conditions.