静动载条件下深部破碎巷道支护设计及稳定性分析

Support Design and Stability Analysis of Deep Fractured Roadway under Static and Dynamic Condition

深部破碎围岩稳定性控制是制约深部金属矿安全高效开采的难题之一。以金川二矿区深部某中段破碎围岩条件下的采准巷道稳定性控制为工程背景,应用Q、RMR、GSI进行岩体质量分级与岩体力学参数估算,分别应用经验法和工程类比法进行采准巷道支护设计,并依据收敛约束法确定合理的释能支护时机。在此基础上,应用UNWEDGE软件对释能支护设计进行安全性评价,并通过RS2数值方法分析支护效果。研究结果表明:对于深部破碎采准巷道一次支护采用锚网喷支护,二次支护采用混凝土衬砌,最佳衬砌支护时机应满足巷道帮位移小于38 mm且顶板位移小于15 mm;静动载下有无支护数值分析结果表明,锚网喷支护满足巷道安全要求,同时对采准巷道围岩结构控制型、应力控制型破坏以及动力失稳破坏等起到良好的控制效果。研究结果为金川二矿区深部破碎采准巷道围岩稳定性控制提供了理论依据与技术支撑。

The stability control of deep broken surrounding rock is one of the difficult problems restricting the safe and efficient mining of deep metal mines.Based on the engineering background of the stability control of mining roadway under the condition of broken surrounding rock in a deep section of Jinchuan No.2 mining area,Q,RMR and GSI are applied to the rock mass quality classification and the estimation of rock mechanics parameters.The empirical method and engineering analog method are respectively applied to the support design of mining roadway,and the convergence constraint method is used to determine the reasonable time of energy release support.On this basis,the UNWEDGE software is used to evaluate the safety of the energy release support design,and the support effect is analyzed by RS2 numerical method.The results show that:For the primary support of deep crushing mining,the anchor net shotcrete support is used,and the secondary support is concrete soil lining.The optimal lining support time should meet the tunnel side displacement less than 38 mm and the roof displacement less than 15 mm.The numerical analysis results show that the anchor net shotcrete support meets the safety requirements of the roadway under static and dynamic load.At the same time,it plays a good control effect on the structure control type,stress control type and dynamic instability failure of the surrounding rock of the mining roadway.The study results provide a theoretical basis and technical support for the stability control of the surrounding rock of the deep crushing mining roadway in Jinchuan No.2 mining area.