Study On Surrounding Rock Control Of Yindonggou Gob-side Entry

Taking the return air chute of 110103 working face in Yindonggou mine as the research object,this paper analyzes the deformation and failure mechanism of surrounding rock of gob driving roadway through field investigation,laboratory test,theoretical research and numerical simulation.According to the characteristics of surrounding rock and its stress distribution,the surrounding rock control technology is studied in order to provide reliable guidance for the size reservation of coal pillar and the design of support scheme.Firstly,through field investigation to understand the general situation of field engineering,combined with the relevant parameters and field conditions obtained from laboratory tests,this paper analyzes the deformation and failure characteristics of roadway surrounding rock.Secondly,the law of overburden movement is one of the key factors affecting the stability of surrounding rock.According to the law of overburden rock collapse,this paper analyzes the stress state of coal body along goaf in time and space,so as to provide guiding basis for tunneling position and tunneling time of goaf roadway.By establishing the mechanical model of coal pillar and according to the design principle of coal pillar width,this paper theoretically designs and calculates the coal pillar width,and obtains the minimum reasonable width of coal pillar.With the aid of numerical software FLAC3D,this paper compares the stress and deformation of surrounding rock of goaf roadway in working face 110103 of Yindonggou mine under different coal pillar widths.Combining theoretical analysis and numerical simulation,it is finally decided that the reasonable width of the coal pillar is 6m.Then,the surrounding rock control technology of roadway,namely support design,is proposed.According to previous studies:bolt preload matching is an indispensable link to ensure the effective control of roadway surrounding rock.For the design scheme of bolt strength and preload matching and bolt cable preload matching,by means of numerical software simulation analysis,it is concluded that the bolt preload of 110103 working face of the mine can be designed as 60kN and the anchor cable preload is 150kN.Finally,an on-site industrial test was carried out.Monitoring and analysis of the deformation of the surrounding rock of the roadway during the mining period of the 110103 return airway along the gob of the roadway section under the design of the coal pillar and support scheme.The results show that the surrounding rock deformation of 110103 goaf roadway in Yindonggou mine is well controlled.Figure 43 Table 13 Reference 107...