破碎围岩山岭隧道施工稳定监测及数值模拟

Construction Stability Monitoring and Numerical Simulation of Mountain Tunnels with Weak Rocks

以某高速公路破碎围岩隧道大变形为工程背景,并以现场调查、数值模拟和现场监测为手段,提出了三台阶七步开挖仰拱紧跟工法。利用Midas GTS建立了三台阶七步开挖法的两个数值模型,结合地质勘查和室内试验数据进行了隧道大变形分析,并将新工法的模拟结果与监测数据进行了对比分析。研究结果表明,所提工法中的仰拱紧跟技术对变形控制起到了较好的作用,不仅可以有效控制隧道施工中的大变形问题,且能缩短工期,提高施工效率,节省工程造价。

Taking the large deformation of a highway tunnel with weak rocks as the engineering background,a three-bench seven-step excavation inverted arch following construction method has thus been proposed by means of an on-site investigation,a numerical simulation and an on-site monitoring.Two numerical models of a three-bench,seven-step excavation method are established by using Midas GTS,followed by an analysis of the large deformation of the tunnel in combination with the geological exploration and laboratory test data,with the simulation results of the new construction method compared with that of the monitoring data.The research results show that the inverted arch following technology in the proposed construction method plays an importart role in the deformation control,which can not only effectively control the large deformation found in tunnel construction,but also shorten the construction period,thus improving the construction efficiency and saving the project cost as well.