波浪作用下系泊沉管的运动响应及缆力分析

Motion Response and Mooring Force Analysis of Moored Immersed Tube Tunnel under Wave Actions

沉管隧道管节系泊过程中,缆绳张力是关键参数,决定着管段的系泊安全。采用结合水动力计算软件AQWA进行理论计算,考虑随机波浪、风及水流载荷的作用以及考虑系泊索的非线性动态特性,探究在极端情况下系泊沉管的运动响应及随机波浪载荷对系泊索力的影响规律。结果表明:沉管运动特性是影响系泊索张力的主要因素,适当增加系泊索预张力和重量可有效限制沉管运动幅度,进而减小系泊索力;沉管系泊水域的水深和沉管干弦对系泊索力有一定的影响。针对研究结果,对沉管系泊系统提出了相应的优化建议。

In the process of mooring of tunnel segments,the mooring force is the key parameter that govern the safety of the immersed tunnel.The AQWA software is used to conduct calculation,considering the action of random wave,wind and current load as well as the nonlinear dynamic characteristics of mooring line,the motion response of mooring immersed tube and the influence of random wave load on mooring line force under extreme conditions are explored.The calculation result shows that the motion of the tube is the main factor that influence the cable force.Properly add the weight of the mooring cable or increase the pre-tensioning force of the cable can decrease the motion amplitude of the immersed tunnel which can lower the cable force effectively.The depth of the water and the freeboard of the tunnel are also the influence factors of the cable force.Based on the study result,optimization suggestions are given for the mooring system of the immersed tunnel.