Optimization and Practice of Support Scheme for Thick Loose Layer and Thin Bedrock Roadway in Zhaogu No.1 Mine
The mining of thick loose layer and thin bedrock coal seam is one of the problems faced by coal production in China.Taking the 16081 upper crossheading of Zhaogu No.1 Mine as the engineering background,five support design schemes were simulated by finite difference software.The optimal support scheme was selected after analyzing the simulation results through three indexes of stress,displacement and plastic zone.On this basis,the field support practice and the roadway deformation monitoring were carried out.The results show that:(1)the strengthening support scheme of"anchor cable net+closed steel frame+floor bolt+floor grouting"has better control effect on the surrounding rock of 16081 upper crossheading.When the monitoring time is 90 d,the relative displacement of the roof and floor of the roadway is about 80 mm,and the relative displacement of the two sides is about 140 mm.(2)Compared with the unsupported roadway,the vertical stress peak of the surrounding rock of the optimal scheme is reduced,and the stress peak is transferred to the shallow part,which appears at about 2 m from the surface of the two sides.The horizontal stress peak area shifts to the shallow part of the floor,mainly concentrates at about 0.9 m from the center of the roadway floor.(3)Compared with the unsupported roadway,the maximum deformation of the two sides of the optimal scheme is 21 mm,which is reduced by about 80.9％.The plastic zone volume of the optimal scheme is only 15.3 m3,which is reduced by about 85.6％.
Thick loose layerThin bedrockSupport scheme optimizationRoadway deformationPlastic zone volume
万方数据
维普
