摘要
位于湖南常吉高速公路上的仲溪隧道为一浅埋连拱隧道,特别是在洞口地段,隧道上部岩体为一明显斜坡,使隧道呈现明显的偏压特性,这就使得隧道不但浅埋而且存在偏压,在施工初期就出现了局部坍塌,为确保工程的正常进行,本文选取了一典型断面作为计算模型,运用FLAC2D,对其在两种不同施工顺序下的施工力学行为进行了模拟计算,通过对比两种施工顺序下围岩的应力、位移以及隧道支护结构中的内力,提出了开挖方案并获得应用,可供浅埋偏压连拱隧道施工工序选择参考。
Zhongxi Tunnel of Chang-Ji Expressway in Hunan Province is a shallow multi - arch tunnel, especially at the region of portal, where the rock mass of the upper portion is obviously a slope, and unsymmetrical pressure will be produced obviously on the tunnel structures. At the initial stages of construction, the rock collapse has occurred within a small region. In order to guarantee normaU construction of the project, a representative section is taken as an example for calculation. and a numerical model is set up by use of FLAC2D in this paper. Considering two kinds of construction sequences, the construction mechanical behaviors are simulated. Through comparison of the stress of the surrounding rock, the displacement of the surrounding rock and the internal forces of the supporting structures in tunnel, an excavation scheme is put forward and then it is applied. This can be reference to the choice of construction sequence for shallow multi-arch tunnels under unsymmetrical pressure.
出处
《地下空间与工程学报》
CSCD
2005年第6期940-943,共4页
Chinese Journal of Underground Space and Engineering
基金
湖南省交通科技项目(200436)
关键词
浅埋
偏压
连拱隧道
施工顺序
shallow
unsymmetrical pressure
multi- arch tunnel
construction sequence
