昔格达地层隧道系统锚杆作用效果及作用机理研究

为探明昔格达地层隧道中系统锚杆的作用效果及作用机理，以冉家湾铁路隧道工程为依托，以有、无系统锚杆分别在深埋与浅埋隧道两种工况下建立相应有限元模型，从锚杆轴力、围岩塑性区范围以及围岩变形位移三个方面分析锚杆作用效果并深入探究系统锚杆的作用机理。结果表明:系统锚杆在拱部作用小，在边墙作用相对较好，表现在位移约束与应力补强效果较突出；系统锚杆在昔格达地层中的作用以围岩补强和成拱作用为主。

Study on Effect and Mechanism of System Anchor Bolt for Tunnel in Xigeda Strata

In order to find out the effect and mechanism of system anchor bolt for tunnel in Xigeda strata, herein the tunnel engineering for Ranjiawan Railway was depended on to establish the finite element models corresponding to deep-and shallow-buried tunnel with or without system anchor bolt, respectively, and to analyze the bolt effects from the aspects of bolt axial force, rock plastic zone and rock deformation displacement, then explore the mechanism profoundly. The result shows that the system anchor bolt has minor effect on the arch, but good on the side wall, manifested by prominent displacement constraint and stress effect after reinforcement; it plays a role of rock strengthening and arching mainly in Xigeda strata.