Research on stability of surrounding rock in super-large-section chamber with fractured soft rock and its control technology
In view of the instability issues of surrounding rock in super-large-section chambers,this study takes the super-large-section chambers of the underground agitation station at Jinfeng Gold Mine as the research object,establishes a rock quality index model for the mining area using the mine's geological drilling database,and based on this model,determines the optimal location for the agitation station construction to be at the 150 m level.Through laboratory tests,field investigations,and ground stress measurements,the parameters and stress distribution characteristics of the surrounding rock were determined.The stability of the chamber after excavation was analyzed using the Phase2 rock mechanics software for numerical simulation.Based on the analysis results and the engineering analogy method,a joint support scheme was proposed for the surrounding rock,which includes pipe-slit bolts,hanging mesh,wet shotcrete,resin bolts,long anchor cables,grouting behind walls,and anti-heave reverse arch concrete.The reinforcement effect was evaluated through numerical simulation and field application monitoring,and the results showed that the maximum deformation of the reinforced chamber was 31 mm,the maximum principal stress was 25 MPa,no damage occurred to the bolts(cables),and all safety factors of the concrete lining units were greater than 1.2.The support structure was in a reasonable and effective stress state,indicating that the chamber remained stable after reinforcement,with good support effects.The research findings have important reference value for similar engineering projects.
fractured soft rocksuper-large-section chambersurrounding rock stabilityunderground agitation stationRQD modelrock qualityground stressjoint support
万方数据
维普
