The Research On Surface Subsidence Due To Mining Horizontal Slice Of Extra-thick And Steep Coal Seam

Based on the actual needs of the extra-thick and steep coal seam due to mining horizontal slice under buildings, railways and waterbodies, the surface subsidence rules is revealed and the angle parameters calculation method is presented by analyzing the observed data and field exploration. A study is made on the law of the strata movement due to horizontal slice mining extra-thick and steep coal using the research means of model experiment and numerial simulation. Mining process is divided into shallow and deep mining phase because the strata movement in the process of mining showed the phased character. Each mining phase shows a movement structure model, such as arch structrue in shallow mining phase, and hinged rock beam in deep mining phase. The law of strata and surface movement and the change law of strata movement parameters is summarized in the control of the two phase. The mechanism character of the strata movement propagation path is reavled, as well as the forms of the strata movement. According to the strata movement mechanism and the different characteristics between mining space and attitude of stratum, propagation angle of extration change based subsidence prediction model and surface movement prediction method is built in the basis the random medium theory. Other extensive work is also made on the application.