Bolt Support Technology of Gateway with High Stress Broken and Swelling Roof

Abstract：In order to effectively solve the support difficulty of the mine gateway with high stress broken and swelling roof, based on the railway rise gateway in No. 10 mining block as the project background, a analysis was conducted on the seam geological conditions and the roof rock softness. Based on the circumstances, a design on the support parameters of the mine gateway was conducted, the authors select- ed the best support plan after support parameters were designed and optimized. The FLAC2D saftware was applied to the numerical analysis on the deformation features of the surrounding rock in the gateway with high stress broken and swelling roof. The horizontal stress concen- trated scope of the roof obtained was 0. 8 m and the vertical stress concentrated scope of the two sidewalls was 1.2 m. The stress and de- formation monitoring and measuring of the surrounding rock showed that the anchoring force of the roof bolt was 75 ~ 86 kN and the ancho- ring force of the anchor was 115 ~ 148 kN. The subsidence value of the gateway roof was 38 mm in average and the average convergence of the two sidewalls was 62 mm. The plan could improve the integrated loading capacity of the gateway support structure, could effectively control the deformation of the surrounding rock in the gateway.