浅埋煤层煤巷掘进滞后支护时间对煤壁稳定性影响的数值模拟研究OA

In order to determine the lagging support time of coal wall on both sides during the excavation of coal roadway in shallow buried coal seam in Qingmieyao Mine,5333 belt transportation road was selected as the research object,and FLAC3D software was used to numerically simulate and analyze the creep law of coal wall on both sides under the condition of different lagging support time in the excavation process.The results show that within 28 days after the excavation of 5333 belt transportation roadway,the relative proximity of the two sides of the coal wall will be kept in a relatively small range if the roof can be supported in time;when the excavation time is more than 29 days,there will be an accelerated creep phenomenon if there is no support for the two sides of the coal wall,the proximity of the two sides of the coal wall will be increased rapidly,with the maximum rate reaching 36 mm/d,and the maximum depth of the plastic zone will be 1.3 m,resulting in the obvious decline in the stability of the two sides of the coal wall.When lagging support was carried out on both sides of the coal wall 28 days after the roadway was excavated,the development depth of the plastic zone was controlled within 0.5 m,and the development depth of the plastic zone was reduced by 61.5%,which fully demonstrated the important role of lagging support in maintaining the stability of the coal wall on both sides of the roadway.