High Strength Stable Type Support Technology of Mining Gateway Under Goaf in Contiguous Seams

In order to solve the H type steel beam bending,support leg bending and inner moving forward,and other problems occurred by large area roof subsidenc e soon after railway gateway driving completed in No.29101 coal mining face of a mine,a site investigation analysis and numerical simulation were applied to study and summary the major factors of the gateway stability lost and failure, the surrounding rock stress and displacement of the gateway under the different support methods an d the bending moment distribution features of the H type steel support.The study results showed that to enhance the support strength,to improve the residual strength 0 f the surrounding rock,to fully play the loading capacity of the surrounding rock and to timely form an effective stable loading structure could control the serious shear a nd swell deformation of the shallow surrounding rocks along the gateway and could be the principle of the design on the gateway support.According to the principle of t he bolt(anchor) support role and the results of the numerical simulation analysis,the paper provided the high strength stable type support based on the high strength pre -stressed bolt and anchor support with the H steel support as the auxiliary.The practical application showed that the support plan effect was excellent and could effectiv e control the surrounding deformation of the gateway.