Study On The Law Of Oversize Fully-mechanized Caving Workface Pressure And Rational Type Selection Of Support In Pingshuo Coal Mine

Based on the adaptability of ground pressure and hydraulic support during the mining process of the oversize fully-mechanized caving workface, the author studied on the law of oversize fully-mechanized caving workface pressure and rational type selection of support in Pingshuo Coal Mine. Through the observation of the site floor specific pressure and ground pressure, the author generalizes strata moving regularity rule of oversize fully-mechanized caving workface intervals and face coal-rock mass destruction. On the analysis of interaction between support and surrounding rock, the mechanical model of whole coal face is established. The regression analysis shows that roof fall is mainly affected by hydraulic support and the distance to face. Based on the simulation analysis of face-to-canopy support parameter, two-column support is better than four-column in the same condition. Mechanics analysis is used on horizontal force, simulation control study is applied for horizontal force affecting the roof fall. As a result, the mechanic model of asymmetric caving arch was built and the author analyzed the influence on the shape of caving arch by horizontal force and the relationship of the height and width of caving arch. Through the analysis and comparison of structural characteristic between two-column support and four-column support to work out the bearing feature of both support, based on which bearing ratio was proposed and finally technological parameter was optimally calculated of fully-mechanized rational support type.