论文部分内容阅读
陡倾小交角层状围岩隧道指隧道轴线与岩层走向一致或小角度相交(一般小于20°),且岩层倾角较大(一般大于40°)的隧道。开挖施工时其层状岩体容易沿层面发生顺层滑移从而引发灾害。目前,隧道开挖使用的锚杆支护结构多沿隧道轮廓线径向布置,而且在隧道横断面上左右对称布置,该锚杆支护结构不适应陡倾小交角层状围岩隧道围岩的破坏机制。针对陡倾小交角层状岩体隧道的地质特征和破坏机制,对其锚杆支护结构系统进行了优化分析,提出了一种适用性更强的锚杆支护系统,该支护结构沿隧道洞周采用非对称非均长布置,能防止围岩发生顺层滑移破坏,有效地控制围岩变形,从而降低隧道开挖施工的风险和费用。
Steeply inclined small-angle bedded tunnels refer to tunnels whose tunnel axes intersect at a uniform or small angle (generally less than 20 °) and have large dip angles (generally greater than 40 °). During the excavation, the stratified rock mass easily slides along the strata to cause disaster. At present, the supporting structures used for tunnel excavation are mostly arranged radially along the contour lines of the tunnels, and are symmetrically arranged on the transverse section of the tunnel. The anchor supporting structure is not suitable for the surrounding rock of the steeply inclined small-angle bedded surrounding rock tunnel Destruction mechanism. Aiming at the geological characteristics and failure mechanism of the tunnel with steeply inclined and small angle of intersection, the optimization of bolting system is presented and a more adaptable bolting system is proposed. The non-symmetrical non-uniform layout of the perimeter of the tunnel can prevent the surrounding rock from sliding and descending, and effectively control the deformation of the surrounding rock so as to reduce the risk and cost of tunnel excavation.