【摘要】 淮南丁集煤矿西部采区南运输大巷埋深达955 m,已显现出深部开挖的特征。为研究深部巷道围岩破裂情况,在该巷道选取2个监测断面(宽5.0 m,高3.8 m),每个断面布置5个钻孔,测量围岩电阻率沿钻孔深度的变化。电阻率是岩石的重要电性参数,岩体的破碎程度对电阻率的影响较大,一般有裂纹的地方,电阻率产生突变。采用ResiTest–4000电阻率测试仪和研制的孔内探头,对钻孔内岩体电阻率进行测试。岩石破碎区电阻率基准值根据每一钻孔电阻率平均值(剔除特异点)确定,大于基准值的为破碎区。根据测试结果,绘制巷道围岩分区破裂图,与钻孔电视观测结果较吻合。结果表明,该巷道围岩有4个破裂分区;破裂分区带的半径与巷道半径基本呈线性关系;巷道周边破裂区宽度最大,平均达到3.12 m,依次分区破裂带的宽度有递减趋势。更多还原

【Abstract】 South transportation roadway of depth of 955 m in Huainan Dingji Mine western coal area has shown the characteristics of the deep excavation.In order to investigate fracturing behavior of the surrounding rock in the deep roadway,two sections(the width is 5.0 m,and the height is 3.8 m) are selected.Five boreholes are drilled as fan array in the arch of the every section.The variation of electrical resistivity of surrounding rock with borehole depth can be measured.Electrical resistivity is one of the important electric parameters for rocks.The degree of rock mass fracturing has great influence on electric resistivity;and generally electrical resistivity changes suddenly in the fractural location.Using ResiTest–4000 resistivity tester and self-developed downhole probe,the electric resistivity of rock mass in the boreholes is tested.A reference value of electrical resistivity on disintegrated zones of rock mass can be determined according to average electrical resistivity(to reject abnormal data) in every hole;and the ones greater than the reference values are disintegrated rock mass.According to the test resultst,he diagrams of zonal disintegration distribution of surrounding rock of the roadway are drawn.In addition,the diagrams are in agreement with ones obtained from borehole TV video.The results show that there are four disintegration zones in the surrounding rock of the roadway;the radius of the disintegrated zones has a linear relationship with the radius of the roadway;the thickness of the disintegrated zones near the roadway boundary is maximal and up to 3.12 m;and the thickness of disintegrated zones decreases in turn with borehole depth.更多还原