基于数值模拟的双隧道净距对地表沉降的影响分析

Analysis of the Effect of the Clear Distance between Two Tunnels on Surface Subsidence Based on Numerical Simulation

摘要: 为了解决设计施工不当引发的地表沉降过大、上方路面塌陷、构筑物沉降等问题。利用MIDASGTSNX软件建立隧道三维数值模型，通过研究双隧道的隧道净距对地表沉降的影响情况。结果表明：双隧道净距较小时，地表沉降曲线呈“V”型，最大沉降位于两隧道中间；当两隧道净距不断增大，地表沉降曲线形状发生改变，逐渐转变为“W”型，地表最大沉降值随着净距增大而减小，且位于先行隧道上方，为保证工程安全，选择双隧道净距为15 m的工况。

Abstract: In order to solve the problems caused by improper design and construction, such as excessive surface subsidence, upper road collapse and structure settlement. The tunnel three-dimensional numerical model is setup by using MIDAS GTSNX software, through changing the clear distance between two tunnels to show the influence on surface subsidence. The results show that: when the clear distance between the two tunnels is small, the surface settlement curve is “V”, and the maximum settlement is located in the middle of the two tunnels; when the clear distance between the two tunnels is increasing, the shape of the surface settlement curve changes, gradually transforming into a “W”, the maximum surface settlement value decreases with the increase of the clear distance, and is located above the first tunnel. The maximum settlement value decreases with the increase of the clear distance, and it is located above the first tunnel, to ensure the safety of the project, choose the working condition that the clear distance between the two tunnels is 15 m.