Research on Optimization Technology of Top Distance and Support Technology for Fast Excavation of Rock Tunnel in Huayang No.1 Mine
In order to improve the excavation efficiency of the low level extraction roadway in the 8412 working face of Huayang No.l mine,a reasonable empty top distance of 3.2 m was obtained through theoretical calculation.Numerical simulation was used to compare the stability of surrounding rock under different schemes,and a reasonable gap of 4 m was determined.The anchor rod spacing was 1 400 mm,and the anchor cable arrangement was in the"2-1-2"formula.The on-site test results show that after the optimization of excavation and support technology,the maxi mum subsidence of the roadway roof is 62 mm,and the maximum displacement of the two sides is 40 mm,with relatively small overall deformation.And the average monthly excavation speed of the tunnel has increased to 200 m,which is nearly twice as high as before,and the application effect is significant.
rocks lanerapid tunnelingempty top distancesupport technology
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