水中悬浮隧道锚索横向动力特性分析

Lateral dynamic characteristics analysis for cable of submerged floating tunnel in water

考虑流体-结构偶联效应和悬浮隧道锚索的几何非线性特点,建立了悬浮隧道锚索非线性振动方程,并通过ANSYS有限元软件的二次编程,在时域内实现了方程求解,分析了悬浮隧道锚索在非线性横向升力作用下的动力特性。计算结果表明:锚索的轴力和锚索中部的最大位移都随锚索的预张力增加而显著下降;在非涡激振动的情况下,随均匀流速度的增加,锚索中部的最大位移有所增加,但是在涡激共振的情况下,锚索中部位移有跳跃性增加;随着锚索长度的增加,锚索中部的最大位移变小,轴力随之增加;锚索的倾斜角度对锚索的轴力和位移的影响基本一致,随角度的增加,轴力和位移均先减小,后增加。

Considering the nonlinear characteristics of submerged floating tunnel（SFT） cable and the lateral dynamic response of structure-fluid interaction（SFI）,a nonlinear dynamic model equation of SFT cable was established in the time domain,the equation was solved by the secondary development of finite element software ANSYS,and the nonlinear dynamic characteristics of the SFT cable was analyzed under the action of lateral lift.The results show that the axial force of the cable and the maximum displacement of the middle part of the cable have a significant reduction with the increasing of cable pretension.The maximum displacement of the middle part of cable has a certain increase with the increasing uniform flow velocity without resonance,and it has a jumping develop with resonance.The maximum displacement of middle part of cable decreases with the increasing of cable length,but the axial force of the cable increases.The inclination of the cable has the similar effect on the displacement and the axial force,the axial force and the displacement increase at beginning and then decrease with the increasing of inclination.