基于流固耦合的富水软岩隧道稳定性分析

STABILITY ANALYSIS OF TUNNEL IN SOFT ROCK SECTION UNDER RICH-WATER BASED ON FLUID-SOLID COUPLING

公路隧道穿越富水软岩段施工时,易导致围岩坍塌、初期支护结构变形等不良现象。文中以雾岭头隧道某浅埋富水软岩段为工程背景,采用有限元软件(MIDAS GTS/NX)建立了考虑不同流固耦合效应的隧道施工模型,研究两种工况下开挖过程中围岩变形特征及支护结构受力状态。结果表明隧道穿越富水地层时,是否考虑流固耦合理论围岩和支护结构都会产生不同程度变形,考虑耦合作用下的拱顶沉降值增大1.63倍,支护结构左右边墙应力集中特征明显。研究结果可为穿越富水软岩段的隧道工程建设提供一定参考,具有工程实用价值。

The construction of highway tunnels through water-rich soft rock sections easily leads to undesirable phenomena such as collapse of the surrounding rock and deformation of the initial support structure.Taking shallowly buried water-rich soft rock section of the Wulingtou tunnel as the case,the tunnel construction model considering different fluid-solid coupling effects is established using finite element software(MIDAS GTS/NX) to research the deformation characteristics of the surrounding rock and the force state of the support structure during excavation under two working conditions.The results show that the surrounding rock and support structure deform to varying degrees under the condition of rich water in soft rock,whether the fluid-solid coupling theory is considered or not.The sediment value of the vault under the coupling effect increases by 1.63 times,and the stress concentration characteristics of the side walls of the support structure are obvious.The results of the research may provide the reference for the construction of tunnels through water-rich soft rock sections and are of practical engineering value.