Mechanical Properties And Stability Control Of Roof Rock Of Weak Cemented Siltstone Roadway

Taking the 3402 working face roadway of Linchang Coal Mine of Youjiang Mining Bureau in Baise,Guangxi as the engineering background,the paper focuses on the roof support and stability control of weakly cemented Siltstone Roadway,in-situ investigation,laboratory test,theoretical analysis,simulation calculation and engineering design are used to study the mechanical properties and Stability Control of the surrounding rock of weakly cemented siltstone Roadway,the main results are as follows:(1)Through on-the-spot investigation,the general situation of the mine geology,the tunnel cross-section parameters,the tunnel surrounding rock deformation and the original support scheme parameters have been mastered,and some rock samples of the roof have been taken,based on the analysis of deformation and failure of roadway,microstructure and physicochemical composition,the instability mechanism of surrounding rock is summarized.(2)The uniaxlal compression test and weak cementation test of rock have been carried out according to the roof characteristics of 3402 working face roadway,and the strength and Hydrolysis test of rock block have been carried out,the results show that the roadway surrounding rock roof loose and weak,low strength,poor self-stability and water softening,the original support effect is not good.(3)According to the deformation characteristics and instability reasons of the surrounding rock of the weakly cemented siltstone Roadway and the test results of the mechanical properties,the reasonable control countermeasures of the stability of the tail teeth of the roadway are put forward,and then the actual economic and site construction conditions of the mine are synthesized,the combined support scheme of "advanced grouting + Roof Bolt + Anchor Cable" is designed.(4)The instability mechanism of roadway surrounding rock is analyzed by Structural mechanics theory and the instability condition is obtained by mechanical analysis.According to the site geological conditions,the original and the new support scheme are simulated by Abaqus numerical simulation software.The results show that the improved support scheme is more effective.(5)Based on the instability characteristics of the surrounding rock of weak cementation roadway in Linchang Coal Mine,the reasonable stability control principle is put forward.Finally,the new design scheme is carried out on site,and the monitoringdata is used to verify and evaluate the support effect.The monitoring results show that the optimized support scheme has good support effect and can maintain the long-term stability of roadway surrounding rock.