移动荷载作用下悬浮隧道动力响应分析

摘要

A submerged floating tunnel is a novel sea-crossing structure suspended under water.In order to analyze the dynamic response of a submerged floating tunnel subjected to moving load,a submcrgcd floating tunnel was simplified as a spaced beam on elastic supports.Considering the fluid inertia effect and damping effect by the Morison equation,dynamic differential governing equations were obtained for the submerged floating tunnel subjected to moving load through modal superposition and Galerkin methods.Meanwhile,the dynamic differential equations were solved numerically by using the fourth-order Runge-Kutta method.The results show that the impact coefficient and acceleration response of the structure are related to the fluid effect.Furthermore,the fluid effect is affected by the length of the structure and mode number.Besides,the tether stiffness is disincentive to the impact coefficient and acceleration response.Moreover,high speed moving load will result in more dramatic fluctuation to the structure.%悬浮隧道是悬浮在水中的一种新型的跨江、海结构.为分析移动荷载作用下悬浮隧道的动力响应,将悬浮隧道简化为等间距弹性支撑梁,基于Morison方程在考虑流体附加惯性效应和阻尼效应的基础上,通过振型叠加法和Galerkin法得到悬浮隧道在移动荷载作用下的振动微分控制方程,并采用四阶龙格-库塔法进行数值求解.结果表明:移动荷载作用下,悬浮隧道的冲击系数和加速度响应与流体作用效应相关,而流体作用效应受结构跨径和振动模态阶数的影响;其次,锚索刚度对移动荷载冲击效应和振动加速度具有一定的抑制作用;再者,高速移动的荷载会引发悬浮隧道结构强烈的波动激荡.