Study on Complex Active Support System of Seam Gateway with Thick Carbonaceous Mudstone Roof

The conventional bolt(or anchor) support method for a large span seam gateway with thick carbonaceous mudstone roof could not solve the key problems of the suspending on the roof with no stable strata above and would be easy to have a roof failing accident occurred.In order to efficiently control the deformation of the gateway and promote the mine safety production,the project group provided a compound active support system to control the large span gateway with the thick carbonaceous mudstone roof.The paper stated the support principle.A mechanics model of the compound active support system was established.The truss anchor structure in the compound active support system was reached to the critical condition of the pre-tension Qy value when the system was balanced.The FLAC5.0 numerical simulation software was applied to calculate,design and optimize the compound active support system plan of the larger span seam gateway with thick carbonaceous mudstone roof in the Pingmei No.8 Mine.The site measurements showed that the max roof subsidence of the gateway was 158 mm and the convergence of gateway cross section was small.The deformation of the gateway was effectively controlled.The FLAC5.0 numerical simulation software had provided the strong references of the application with different complicated geological conditions and could have a good outlook for the promotion and application.