Study On Floor Heave Mechanism And Control Technology Of High Stress Soft Rock Roadway In No.1 Coal Mine Of Pingdingshan Coal Industry Group

The treatment of floor heave in soft rock roadway with high stress is a long-term puzzle for mine safety production.In this paper,based on the engineering background of Pingmei No.1 Coal Mine three-level down-950 horizontal return air roadway,according to the detection of surrounding rock structure,the structural characteristics and failure range of surrounding rock are analyzed;The physical and mechanical properties and mineral components of the floor strata are measured by field sampling.It is found that the floor of the roadway is composed of sandy mudstone and expansive clay minerals.It is revealed that the weak lithology of the floor is an important reason for floor heave;Based on the crustal stress test data,the relationship between the original rock stress and the floor heave of the roadway is analyzed;Taking the original support system of the roadway as the research object,the influence of the support strength of the floor on the floor heave is analyzed;the process and amount of the floor heave caused by the surrounding rock stress,rock expansion and plastic deformation are analyzed through theoretical calculation and empirical formula,and a set of mechanical model is put forward to explain the floor heave of the roadway,and the mechanism of the floor heave of the roadway is analyzed theoretically.Based on the analysis and summary of the main influencing factors and mechanism of floor heave,this paper points out the way to control the floor heave of the roadway,and makes a comparative analysis of the floor heave of the roadway when the original supporting scheme,floor pressure relief,floor anchoring and floor grouting technology are used by FLAC numerical simulation software,and analyzes the stress distribution and plastic area of the surrounding rock,Therefore,two floor heave control schemes are proposed,which are anchor injection reinforcement and floor blasting pressure relief.The industrial test results show that the floor heave control effect of-950 return air roadway is good,The roadway floor can ensure long-term stability.The research results of this paper can provide some reference for similar roadway floor heave control problems.