基于有限元模型的共建隧道开挖施工影响分析

Analysis of the Impact of Co-construction Tunnel Excavation Construction Based on Finite Element Model

针对新建交叠隧道施工对既有隧道影响的工程问题,提出了一种基于二维、三维相结合的数值模拟分析方法。采用有限元软件建立了交叠隧道穿越施工的三维有限元模型,并根据最不利影响断面建立了二维有限元模型。对比了新建交叠隧道明挖、暗挖施工阶段对既有隧道结构响应的影响,结果表明:新建交叠隧道明挖阶段对既有隧道的影响最大,既有隧道衬砌结构位移峰值为2.34 mm;二维不利断面的结果表明,新建交叠隧道施工下既有隧道的沉降变形大于水平变形,沉降变形峰值为2.36 mm,水平变形峰值为1.4 mm。

In view of the engineering problems of the influence of the existing tunnel of the new overlapping tunnel construction team,a numerical simulation analysis method based on the combination of two-dimensional and three-dimensional is proposed.The three-dimensional finite element model of overlapping tunnel crossing construction is established by using finite element software,and the two-dimensional finite element model is established according to the most unfavorable section.The results show that the open excavation stage of the new overlapping tunnel has the greatest impact on the existing tunnel,and the peak displacement of the existing tunnel lining structure is 2.34 mm;The results of two-dimensional adverse section show that the settlement deformation of the existing tunnel under the construction of the new overlapping tunnel is greater than the horizontal deformation,and the peak value of settlement deformation is 2.36 mm,and the peak value of horizontal deformation is 1.4 mm.