平行4孔山岭隧道渗流场解析解及影响参数分析

Analytical Solution of Seepage Field in Parallel Four-Tube Mountain Tunnel and Influence Parameters

为研究平行4孔山岭隧道渗流场,综合镜像法与叠加原理推导考虑衬砌时平行4孔隧道渗流场的解析解,将该解分别退化为单孔、双孔及3孔隧道渗流场解析解后与现有研究进行对比,并结合数值模拟计算结果,对解析解的正确性进行验证,继而讨论隧道间距、隧道相对尺寸及初期支护参数对4孔隧道涌水量及初期支护外水压力的影响规律。研究结果表明:1)对于平行4孔隧道渗流场来说,间距变化带来的影响在相邻隧道间表现更加显著,当间距超过20倍隧道半径时则可忽略不计;2)随着某一隧道直径的增大,该洞涌水量随之增大,其余隧道涌水量随之减小;3)随着初期支护渗透系数的减小及其厚度的增大,隧道涌水量逐渐减小,初期支护后水压力逐渐增大,隧道间相互影响逐渐减弱。

To investigate the seepage field of parallel four-tube mountain tunnels considering lining, the analytical solution of the seepage field of parallel four-tube mountain tunnels is derived using a comprehensive image method and the superposition principle. Then, the solution is degenerated into the seepage field analytical solutions of single-,double-, and triple-tube tunnels and compared with existing results. Moreover, the analytical solutions are validated using numerical simulation results, and the influence laws of tunnel spacing, tunnel relative dimension, and primary support parameters on water inflow and primary support outer pressure are analyzed. The results reveal the following:(1) The influence of tunnel spacing between adjacent tunnels is more significant on the seepage field of parallel fourtube tunnels, but the influence can be ignored if the tunnel spacing is >20 times the radius of the tubes.(2) If the diameter of one tube of the tunnel increases, its water inflow increases accordingly, decreasing the water inflow in the other three tubes.(3) With a decrease in the permeability coefficient and an increase in the thickness of the primary support, the water inflow in a tube gradually decreases, the water pressure after the primary supporting gradually increases, and the interactions between tubes gradually weaken.