路堑开挖对既有铁路隧道影响数值分析

Numerical Analysis on Influence of Cutting Excavation on Adjacent Existing Railway Tunnel

随着城市的扩大,市政道路的快速发展使新建道路越来越多的临近或穿越既有地下建(构)筑物。依托某市政道路与相邻铁路隧道工程,采用Midas GTS软件计算分析路堑开挖过程中隧道受力变化及变形情况。研究结果表明:地层结构法能反映出地层岩性对偏压隧道内力的影响,地层弹性模量E与隧道外侧拱肩弯矩M曲线为幂函数型。路堑边坡坡脚与隧道中线距离d影响隧道衬砌内力,d-M曲线存在的拐点可供设计参考。

The expansion of city and rapid development of municipal roads make more and more new roads get close or cross over the existing underground structures. Based on a municipal road and adjacent railway tunnel engineering, the Midas GTS software is uhilized for calculating and analyzing the stress change and deformation of the trunnel in the course of cutting excavation. The results show that ： stratum structure method could reflect influence of stratum lithology on internal force of unsymmetrieally loaded tunnel; the curve of stratum elastic modulus E vs. tunnel lateral shoulder bending moment M is power function; the distance d between the toe of cutting slope and the central line of tunnel affects the internal force of tunnel lining; and the inflection point of d-M curve may be referred in design.