Stability Analysis And Reinforcement Methods Of The Goaf In Nanguanzhuang Coal Mine

This paper takes GongGang NanGuanZhuang coal mined-out area of Gongyi(JiaoTongZhuo to Xiaodian Dian)reconstruction project as the research background,conducts an overview background analysis along the extension of the highway along the coal mine area of geological overview and engineering geological condition,and it concludes the law of surrounding rock movement and its deformation in gently inclined coal seam.By using empirical formula calculation method and GTS numerical simulation method,the law of movement and deformation of surrounding rock and surface are compared.According to the above correlation analysis,the impact of the district on the highway reconstruction and expansion project and the stability of subgrade after grouting,the main conclusions of the study are as follows:According to the results of stress cloud simulation,it can be concluded that the stress concentration phenomenon occurs at both ends of the coal mined area and both ends of coal pillar after coal mining.The failure of the gob area is dominated by shear failure.After the construction of the expressway,under the action of long-term additional load,coal pillars adjacent to the gob area will be unstable under load and generate additional settlement,which will accelerate the residual deformation.Based on the analysis of gob area governance principles and relevant standards and norms,the comprehensive comparison and selection of the advantages and disadvantages and the adaptation characteristics of the common govement management methods,the final grouting method is finally determined and the GTS numerical simulation method is used to compare the stress and strain characteristics and effects of the surrounding rock after grouting.Cloud computing results show that the surface deformation before and after grouting experiences great changes,and the surface displacement and settlement after grouting are significantly reduced.In terms of physical and mechanical properties,the physical and mechanical properties of surrounding rock after grouting increased,and the stress concentration scope of coal mining goaf was significantly reduced,and the surface roadbed deformation decreased significantly.Therefore,grouting treatment greatly enhances the foundation bearing capacity and stability of the coal mined area.It can effectively prevent road cracking,uneven settlement and other road diseases to ensure the long-term safe operation of highway projects so as to achieve a more ideal governing effect.