膨胀软岩巷道支护数值模拟研究

Study on Numerical Modeling of Swelling Soft Rock Roadway

膨胀性软岩巷道开挖后存在膨胀变形破坏严重、返修频繁、支护成本居高不下的难题。为实现巷道的安全经济使用,提出了“树脂锚杆+锚网+U型可伸缩钢拱架”的主被动相结合的联合支护方案,对不同支护参数下的围岩变形进行了数值模拟研究,计算结果表明:未支护情况下,巷道底鼓与顶板沉降最高可达125 cm,并在巷道周围形成了(0.35~0.75) MPa的压应力;数值锚杆间排距0.8 m、锚杆长度1.8 m、拱架间距0.5 m时能够很好的控制膨胀性软岩的变形,同时降低支护成本,为澜沧铅矿巷道支护提供依据,并对类似矿山提供借鉴。

After excavation of swelling soft rock roadway,it has the following problems,swelling deformation,severe damage,frequent reworking,high retaining and protecting cost,in order to achieve safe and economical use of roadway,it is proposed to use joint support scheme that a combination of active and passive ways"resin anchor bolts+bolting and metal mesh+U type retractable steel arches",the numerical modeling study was carried out for deformation of surrounding rock with different retaining and protecting parameters,the calculation results show:the height of roadway floor heave and roof settlement can reach to 125 cm without retaining and protecting,and the pressure stress(0.35~0.75)MPa was formed around the roadway;the array pitch among numerical anchors is 0.8 m,the length of rock bolt is 1.8 m,the deformation of swelling soft rock can be controlled well when the space among arch is 0.5 m,and at the same time,the retaining and protecting cost can be decreased,it can provide references to roadway retaining and protecting of Lancang lead mine,as well as to the similar mines.