高强度洋流作用下沉管的力学性能研究

Study on Mechanical Properties of an Immersed Tunnel Element under High-intensity Ocean Currents

沉管水下沉放中,管节与船舶采用缆索连接吊放下沉。为解决外海复杂海况条件下,船管缆系耦合受力的状态与水下管节的位移不受控和缆力超限的问题,通过数值仿真计算和物模试验相结合的方式,分析了不同沉放深度的沉管沉放过程中,船舶受外载荷和管节水下受水动力双重作用时的动力响应情况。通过计算和试验,开展了自由状态下的衰减试验、系泊系统下模型单自由度运动衰减试验、作业状态下沉管和安装船运动响应及各缆绳的受力测量,得到系泊缆、沉管吊缆和安装缆,在浪、流组合作用下的受力和水下运动位移情况,选取了适用于本项目管节沉放施工缆系的关键力学取值,并进行了工程应用验证和对比分析,证明了该研究成果的正确性,研究成果可为类似工程大型构件水下精确沉放和施工提供技术依据。

During the immersion operation of an immersed tunnel element,the immersed tunnel element is always hung by vertical lines and then connected to the immersion installation vessel.It is difficult to accurately determine the force of the vertical lines and the motion state of the immersed tunnel element due to the action of high-intensity ocean currents in the process of hoisting.Experimental investigation on motion responses of an immersed tunnel element under the action of waves and highintensity ocean currents was carried out.The forces on the vertical lines,mooring line and installation cable were collected and the influence of waves and high-intensity ocean currents on the forces was analyzed.The displacement in six directions of the immersed tunnel element during the process of sinking was recorded in real time and the displacement data were used to achieve high precision installation of the immersed tunnel element.The numerical simulation of the sinking of the immersed tunnel element was carried out.Comparison of the experimental results with the numerical simulation results shows that the experimental results are in good agreement with the simulation ones.The numerical analysis method can be used to simulate similar engineering operations.