Green coordinated mining technology of strip mining roadway backfilling method

In order to reduce the damage of surface and ecological environment in Northwest China caused by high-intensity mining, a new coordinated mining method mixed with“strip mining roadway backfilling method”of partial mining was proposed according to the advantages of strip mining method and backfill mining method.The theoretical analysis and physical simulation method were used.Then the principle of determining the width left of strip mining, the filling width in gob-side entry retaining and the filling rate were given. Meanwhile, the mechanism of coal pillar stability improved by filling body and the overburden stability of backfill mining were also analyzed. The condition of 22407 work face in Halagou coal mine was taken as a model for the research, and the reasonable mining parameters were determined and the numerical simulation was carried out. The results demonstrated that the maximum subsidence of the No.4 sub-key strata was 12 mm after the mining size reached critical extraction.It also inferred that there was no subsidence on the surface, which achieved a good control effect of surface subsidence.The technology provides a new mean to reduce the cost of backfilling and protect the ecological environment.