组合支撑工法在岩石隧道支护中的应用

Application of composite bracing method in rock tunnel support

针对传统隧道施工工法在大断面隧道中存在效率低的问题,提出钢-架-岩墙组合支撑的施工方式,以室内模型试验为研究手段,结合实际隧道施工工程,研究该施工方式在动态施工过程中围岩力学特性响应。结果表明:4#开挖之前对支护结构的扰动最大,其内力增长在这段时间上升较快;整个开挖过程隔壁受力最大,且隔壁受力大小受到开挖的影响最大,支护结构能有效地减缓隔壁的应力增长;围岩的变形主要在开挖前期,到4#后围岩变形处于稳定阶段。上部围岩和下部围岩开挖主要影响的分别是拱顶和仰拱以及左右拱脚的变形。

In view of the low efficiency of traditional tunnel construction method in large-section tunnel,this paper puts forward the construction method of steel-framerock wall combination support.Taking the indoor model test as the research method and combining with the actual tunnel construction project,the mechanical characteristic response of surrounding rock in the dynamic construction process of this construction method is studied.The results show that the disturbance to the supporting structure is the largest before 4^(#) excavation,and the internal force increases rapidly during this period.During the whole excavation process,the stress next door is the largest,and the stress next door is the most affected by the excavation.The deformation of surrounding rock is mainly in the early stage of excavation,and the deformation of surrounding rock is in the stable stage after 4^(#).The excavation of the upper and lower surrounding rocks mainly affects the deformation of the arch,the invert and the left and right arches respectively.