Study On The Prediction Model Of Residual Ground Movement And Deformation Above Old Mine Goaf In Mountainous Area

Coal mining is an indispensable work in the national economic development of our country.However,while coal promotes economic development and the people's living standards improve,it also brings a series of serious negative effects,especially in the construction of surface engineering in the old goaf.It is necessary to analyze and judge the stability of the surface,which involves the residual deformation of the old goaf in mountainous area.Based on the analysis of the geological and mining conditions of the mining area,this paper is based on the consolidation and analysis of a large number of observational data from observational stations.In this paper,the law of residual deformation in old goaf in mountainous area and the prediction model are studied.Through the simulation experiment of similar materials and the rupture process of overburden moving in old goaf,the law of residual deformation and the forming mechanism of residual deformation are analyzed.The applicability of the residual subsidence model is verified by the residual subsidence data of Xiqu mine and the simulated experimental data of similar materials.The main work and conclusions are as follows:(1)The moving deformation data of observation stations in mining areas are handled and analyzed in detail.Based on the values of subsidence and horizontal movement deformation of the observation lines in different mining areas and in different directions,the law of residual deformation in mountainous area are obtained.(2)Taking ground deformation observation station of a mine as a model,a similar material simulation experiment is carried out.The law of residual deformation is obtained.It is concluded that the position of maximum subsidence is related to the roof fracture of the working face;The maximum subsidence value is always inclined to the open hole;After the mining stoppage,the weathering layer tends to stabilize,the residual deformation is very small and slow;and the residual deformation will notchange the shape of the subsidence curve of the weathered layer.(3)The mechanism of residual deformation of old goaf in mountainous area is obtained by analyzing the rupture process of overburden in old goaf.Through the study of the prediction model of the residual settlement in the old goaf of the mountain area,the results are as follows: The logarithmic curve model,power curve model and improved hyperbolic model are more suitable for predicting the residual subsidence of the mountain surface,and the residual prediction value of the modified hyperbolic model is slightly smaller than that of the logarithmic curve model and the power curve model.(4)According to the model curve of parameter change and the law of model parameter change range,the correlation analysis of physical meaning of model parameter is made,and the logarithmic curve model is found to be more suitable for predicting surface residual subsidence in old goaf in mountainous area.The logarithmic curve model has clear correlation with the physical meaning.The application of the logarithmic curve model is verified by the data of the residual subsidence in the Xiqu mine and the analogue observation of the similar materials.