波浪场中水中悬浮隧道动力响应的研究

针对水中悬浮隧道在波浪力作用下动力响应的问题,通过Hamilton原理推导得到了悬浮隧道管段和锚索的运动控制方程,同时考虑了锚索横向和轴向变形之间的耦合作用,建立了悬浮隧道的动力响应模型,在时间域内采用逐步积分法迭代求解其运动控制方程。波浪力采用Airy线性波理论和Morison方程计算。计算结果表明:当锚索长细比较大时,锚索的自振模态会被激发,其横向和轴向变形之间的耦合作用不可忽略。随着入射波高或悬浮隧道重浮比的增加,悬浮隧道的横荡位移以及横摇角增大,但结构的垂荡位移以及锚索中的应力受波浪的影响较小。

RESEARCH ON DYNAMIC RESPONSE OF SUBMERGED FLOATING TUNNEL TO REGULAR WAVE FORCES

The dynamic response of a submerged floating tunnel due to regular wave forces is investigated. The equations of motion and boundary conditions are derived using Hamiltonian variation principle. The dynamic model of the submerged floating tunnel is presented, considering nonlinear coupling between the axial and transverse vibrations of the tether. The nonlinear coupled partial differential equations are solved numerically using the finite difference approach. The wave forces on the tunnel tube and the tether are calculated using Airy’s linear wave theory and Morison’s equation. The simulated results show that if the length of the tether is long enough so that its frequency of self-vibration is in the range of the wave frequency, self-vibration modes of the tether are excited. And the coupling effect between axial and transversal vibrations of the tether can not be discarded. As the wave height or the specific ratio of the tunnel increases, the surge and sway responses increase too, but the heave response and the stress in the tether are hardly affected by the wave height.