基于流固耦合的水底隧道仰拱受力分析与优化

目前,国内外学者对用于铁路和公路交通的山岭隧道断面形式做了不少研究,并得出一些有价值的结论。但是,研究结论应用于水底隧道是否同样能满足衬砌结构受力合理的要求,是值得研究的问题。矿山法修建大断面铁路和公路水底隧道,其断面形式主要采用马蹄形断面,并设置仰拱来控制围岩位移及改善衬砌结构受力。本文以厦门东通道海底隧道为工程背景,采用三维有限差分软件FLAC3D进行流固耦合分析,研究仰拱曲率半径及仰拱部位的防排水措施对围岩位移及衬砌结构受力的影响,优化水底隧道断面形式,以指导大型跨江海的水底隧道的设计和施工。

Analysis of Optimizing Cross-section Shape of Subsea Tunnel

Until now,domestic and foreign scholars have done quiet a lot of studies on cross-section forms of railways and highway tunnels and have drawn some valuable conclusions.But whether the conclusions are reasonable when they are applied in subsea tunnels,it remains a problem to study.Subsea tunnels with large cross-sections are often designed in the horse-hoof shaped cross-section and with an inverted arch to control adjoining rock displacement and improve mechanical characteristics of the lining structure.In the paper,taking the Xiamen east passageway,the Xiang’an Subsea Tunnel under construction,as an example,adopting the fluid-mechanical interaction method by use of the three-dimensional finite differential software,the influence of the curvature radius of the inverted arch and the inverted arch waterproof and drainage measures on adjoining rock displacement and improvement in mechanical characteristics of the lining structure is studied to optimize the cross-section form of the subsea tunnel,and give reference to design subsea tunnels and construction of large-scale across the water.