Optimization Analysis Of Surrounding Rock Stability And Supporting Structure Of Dongfeng Shaft Ingate In Qinan Mine

Ingate is the connecting part of shaft shaft and horizontal roadway at the bottom of shaft.It is located at the throat of mine.It has long service life,complex structure,large size and dense nearby chamber.With the increasing depth of the new mine,compared with the shallow stratum,the original rock stress of deep well ingate is large,the stability of surrounding rock is poor,and the blasting operation of nearby roadway and chamber is frequently disturbed,so deep well ingate and adjacent shaft walls are often damaged,which seriously threatens the safety of mine production.Therefore,this paper takes ingate of Dongfeng Well of Qinan Coal Mine as the engineering background,adopts the method of combining theoretical analysis,numerical calculation and field test to carry out the stability analysis of surrounding rock of Matoumen systematically.The main research contents and results are as follows:(1)According to the engineering geological conditions of ingate in Dongfeng Well of Qnan Coal Mine,after obtaining the physical and mechanical parameters of surrounding rock and the mechanical parameters of supporting structure,FLAC3 D numerical software was used to establish the initial numerical model of supporting structure.The excavation calculation is carried out in sequence.Two analysis methods are used: stress-strain cloud map analysis of surrounding rock,stress-strain analysis of surrounding rock and axial force of anchor bolt and cable evolution with numerical calculation steps.The analysis of stress-strain cloud map results shows that the ingateshaft wall connection and ingate-lining are prone to support failure,and strengthening measures should be taken.The analysis of the evolutionary law of the numerical calculation steps of the stress-strain of surrounding rock and the axial force of anchor bolt shows that the stress and strain of the secondary lining of ingate should be paid attention to.(2)The optimized support scheme is proposed based on the analysis results of the initial support scheme.According to the optimized support scheme,the numerical model of optimized support scheme is established.Using the same analysis method as the initial support scheme,the numerical simulation results of the optimized support scheme are analyzed and compared with those of the initial support scheme.According to the comparison results,the stress-strain and evolution law of the ingate-shaft wall connection and ingate-lining in the optimized support scheme are better than those in the initial support scheme,which proves that the optimized support scheme can better control the surrounding rock surrounding ingate-wall.(3)According to the actual engineering geological conditions of Qinan mine,the monitoring scheme of ingate lining structure is designed,and the data is collected and analyzed.By comparing the data collected from the site with the results of the optimized support scheme,it is concluded that the optimized support scheme can better reflect the change law of the surrounding rock of ingate in Dongfeng well of Qinan Mine,and can ensure the safety and stability of ingate.Figure [52] Table [8] Reference [94]...