麦垛山煤矿巷道围岩地质力学测试试验

Geo-mechanical testing of surrounding rocks in roadway of Maiduoshan coal mine

为进一步优化麦垛山矿井巷道围岩支护方案,对麦垛山矿井巷道的地应力和巷道围岩强度进行原位测试,利用钻孔窥视法观测巷道围岩结构,揭露煤矿巷道围岩结构形态,选取合适测点测试水压致裂地应力,采用钻孔触探法测试围岩强度;分析麦垛山矿井6煤所处的围岩地质力学分布特征和力学参数。测试结果表明:麦垛山矿井最大水平主应力平均值为15.2 MPa,最小水平主应力平均值为8.17 MPa,垂直主应力平均值为13.94 MPa,试验区地应力场为中等应力值地区;区域巷帮6号煤平均强度为28.16 MPa,煤质较坚硬,在巷道围岩10 m范围内,由浅及深分别为粉砂岩、粗砂岩和粉砂岩;岩体强度依次增大,在4.9 m处岩体强度提升95.41 MPa。

In order to optimize the surrounding rock support scheme for the roadway of Maiduoshan coal mine,the in-situ test of ground stress and surrounding rock strength in the roadway of Maiduoshan coal mine was carried out.The structure of the surrounding rocks in the roadway was observed by the borehole peeping method,and its morphology was thus revealed.The appropriate measuring points were selected for the test of ground stress under hydraulic fracturing.The surrounding rock strength was tested by the borehole penetration method.The geomechanical distribution characteristics and mechanical parameters of surrounding rocks in the No.6 coal seam of Maiduoshan coal mine were analyzed.The test results show that the average value of the maximum horizontal principal stress in Maiduoshan coal mine is 15.2 MPa,and that of the minimum horizontal principal stress is 8.17 MPa.The average value of the vertical principal stress is 13.94 MPa.The ground stress field in the test area is a medium stress value area.The average strength of surrounding rocks in the No.6 coal seam in the region is 28.16 MPa,and the coal is relatively hard.In the range of 10 m of surrounding rocks in the roadway,there are siltstone,coarse sandstone,and siltstone in different depths.The strength of rock mass increases,and the strength of rock mass increases by 95.41 MPa at 4.9 m.