Impact characteristics and mechanical analysis to study coal bump under syncline effect in mining roadway

In order to explore the action mechanism of the syncline on the coal bump of the mining roadway,this paper takes the 21221 working face of a mining area in Henan as the research background,and adopts the combination of mechanical analysis,CDEM numerical calculation and field practice. The law of impact characteristics is studied. The mechanical model and numerical calculation model of the mining roadway under the syncline effect are established,and the changing 〖JP+2〗trend of the surrounding rock energy of the〖JP〗 mining roadway under the syncline effect with the influence of mining is analyzed. The following 〖JP+2〗conclusions are drawn:① The surrounding rock of the〖JP〗〖LM〗mining roadway floor under the syncline effect The stress concentration is large,and the impact of the bottom plate is easy to occur. The stress concentration of the surrounding rock at the side is relatively high,which can cause the impact of the side. The surrounding rock stress of the roof is small,and the roof impact is not easy to occur; ② The energy of the surrounding rock of the mining roadway under the action of syncline In general,the influence of mining first increases sharply,then continues to be stable,then decreases suddenly,and finally increases steadily to a certain stress state,or remains stable; ③ The deformation of the surrounding rock of the roadway at the syncline axis is dominated by the bottom heave. ,the deformation of the surrounding rock of the roadway in the syncline wing is the simultaneous deformation of the floor and the side,and the deformation of the surrounding rock of the roadway at the syncline axis is larger than that of the syncline wing. The deformation of the surrounding rock at the depth of 1-3 m in the roadway floor is severe,and the surrounding rock at the depth of 5-8 m at the floor is relatively stable,while the deformation of the surrounding rock at the depth of 1 m in the roadway floor of the syncline wing is significantly larger than that of the surrounding rock at the depth of 2-8 m at the floor. The mechanical analysis and field application show that it is in good agreement with the numerical calculation results.