Study On The Strata And Surface Movement Regular Of The Weakly Cemented Rock High Intensity Mining

In this paper,basing on the geological and mining conditions of Ying Panhao mine 2201 working face,through on the analysis of the measured data、numerical simulation and the similar material simulation in order to study surface and rock mobile deformation law on the weakly cemented rock high intensity mining.The principal outcomes are as follows:1)Field rock sampling in the Ying Panhao mine and doing mechanics experiment.The experiment results show that 90% of rock compressive strength is less than 30 MP,and strata structure most is argillaceous cementing,it has Poor cementation、easily weathered 、 sensitive to disturbance and so on physical properties.So,determined the overlying strata of Ying Panhao mine belong to the weakly cemented rock.2)According to the field measured data,to draw The surface movement deformation curve,revealing the change of the surface dynamic movable deformation rule on the weakly cemented rock;And further detailed analysis the geological and mining parameters and rock formations between Ying Panhao mine and adjacent Xiao Jihan mine,determining the surface deformation prediction parameters value of Ying Panhao mine 2201 working face by analogy method.3)Based on numerical simulation method,what has been studied that the surface and rock movement distortion rule and the change rule of rock internal stress field with plastic zone between mining all height at one time(high intensity mining)with slice mining,that it is more suitable mining all height at one time(high intensity mining)in the weakly cemented rock condition has been revealed.4)Combined theoretical analysis with the similar material simulation result,that Immediate roof stress is different function with distance open-off cut different has been obtained;And under the high confining pressure state,the weakly cemented rock easily occur fake plastic bending because of its physical properties,these“fake plastic body”interior have yielded fissures with normal stress different point of view,and it still regard as“simply supported beam”equilibrium structure that fixed at both ends、intermediate suspension;As for ground movement and deformation,subsidence curve rate of convergence is slower than general geological conditions,and subsidence values are relatively small.5)Based on the study of the weakly cemented rock strata dynamic movement process,established the strata movement mechanics model.And regard the mechanical model as the theoretical basis,combined with material mechanics knowledge,derived a new forecasting method of weakly cemented rock mining caving zone height.6)Having analysed the four agents for the weakly cemented rock subsidence value far less than east soft rock of china subsidence value.Three secondary factors: weakly cemented rock hydration expansion factor、like“grouting separated strata zone in overburden”factor 、 quicksand liquidity factor;one major factor: thickness characteristics of rock formations.This feature make it like the hard rock formation in eastern coal mines which prevent the moving deformation transfer from the rock to the surface.