Clarifying the hydroelastic dynamic response of submerged floating tunnel (SFT) is an important prerequisite for its safety design. Currently, most of the research focuses on theoretical analysis and numerical simulation, and lack of relevant 3D model tests. In this series of studies, 3D entire long span experiments were carried out to systematically study the hydroelastic response mechanism of the SFT. The practical end constraint, the elastic deformation along the tunnel and the coupling effect between the tube and the mooring system was entirely experimentally simulated. Taking the catenary as the mooring system and perpendicular regular waves action, this paper analyzes the 3D hydroelastic response characteristics of the submerged floating tunnel under different wave periods and end pretension conditions, the tube displacement, acceleration and mooring tension along the tunnel were carefully measured. The test results show that the wave period has a significant effect on the displacement and acceleration of the tube, especially when the wave period is close to the structure natural period, the amplitude reaches the maximum, and the displacement and acceleration of the tube reach the maximum at the mid-span. Both horizontal and vertical displacement and acceleration increase first and then decrease with increasing the relative frequency f/fN and KC number. With the increase of the end pretension, the maximum displacement or acceleration amplitude decreases, and the response peaks shift to the direction of low KC number. After applying the end pretension, the horizontal displacement and acceleration amplitude of the tube decrease, but the vertical displacement and acceleration amplitude increase. Increasing the end pretension will increase the mooring tension, and the tension amplitude of the waveward side is always higher than that of the leeward side.

中文翻译：

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悬链线系泊约束和垂直规则波浪作用下整个大跨度水下浮隧道三维水弹性响应试验研究


明确水下浮隧道 （SFT） 的水弹性动力响应是其安全设计的重要前提。目前，研究主要集中在理论分析和数值模拟上，缺乏相关的三维模型测试。在这一系列研究中，进行了 3D 全长跨度实验，系统研究了 SFT 的水弹性响应机制。实际的末端约束、沿隧道的弹性变形以及管道和系泊系统之间的耦合效应完全是通过实验模拟的。本文以悬链线为系泊系统，以垂直规律的波浪作用，分析了不同波期和端部预紧条件下水下浮隧道的三维水弹性响应特性，仔细测量了沿隧道的管道位移、加速度和系泊张力。试验结果表明，波周期对管的位移和加速度有显著影响，特别是当波周期接近结构自然周期时，振幅达到最大，管的位移和加速度在跨中达到最大。水平和垂直位移和加速度均随相对频率 f/fN 和 KC 数的增加而先增大后减小。随着端部预紧力的增加，最大位移或加速度幅值减小，响应峰向低 KC 数方向移动。施加末端预紧力后，管材的水平位移和加速度幅值减小，但垂直位移和加速度幅值增加。 增加端部预紧力会增加系泊张力，向浪侧的张力幅值总是高于背风面的张力幅值。