Abstract：For most metro tunnels built in big cities, the shield method or underground excavation construction methods have been frequently adopted in the design and construction scheme of twin tunnels. In urban areas with crowded underground space, it is important for engineers to assess the influence of constructing new twin tunnels on existing tunnels. As we know, assessing the deformation magnitude of existing tunnels induced by the construction of new twin tunnels rationality and rapidly is crucial to the safe operation of existing tunnels and successful construction of new tunnels. In consideration of the superposition effect of twin tunnels excavation on existing tunnel structure, a two-stage method is proposed for determining the longitudinal deformation of existing metro tunnels caused by the excavation of adjacent twin tunnels. In the first stage, the impact of twin underlying tunnels on the existing tunnel is regarded as the superposition of two separate modified Gauss-distributed loads imposed by two single tunnels. In the second stage, the existing tunnel is simplified as the Euler-Bernoulli beam located on Pasternak foundation. Furthermore, differential equations for the problem can be analytically solved using the Galerkin method. By comparing with the measured results, the proposed prediction method is verified for its rationality and reliability.
白雪峰 王梦恕. 双线隧道开挖对邻近隧道影响的两阶段分析方法[J]. 土木工程学报, 2016, 49(10): 123-128.
Bai Xuefeng Wang Mengshu. A two-stage method for analyzing the effects of twin tunnel excavation on adjacent tunnels#br#. 土木工程学报, 2016, 49(10): 123-128.
