【摘要】 为了研究波流环境中浮桥通载时的动力特性,探讨通载速度及波流联合作用对浮桥动力响应的影响,本文采用势流理论对浮桥所处流场的速度势进行分析,采用莫力森公式计算浮桥受到的水阻力,同时考虑多轴移动荷载的影响,建立系泊浮桥的时域运动方程;并对不同工况下浮桥的运动响应及系泊力进行了计算,在计算中考虑了瞬时湿表面变化对浮桥浮力及水阻力的非线性影响,通过计算得到了不同行驶速度、不同波况下浮桥各桥节的运动响应及系泊力时程曲线。结果表明:车辆行驶速度对浮桥桥节垂荡、纵摇响应及系泊力均具有明显影响,桥节垂荡、纵摇及上游系泊缆张力峰值随行驶速度增大而增大;通载浮桥中部桥节的系泊缆张力最大值小于两侧桥节系泊力最大值;波浪作用下桥节的运动响应及系泊力与车辆荷载引起的运动响应及系泊力具有一定程度的叠加效应,特别是垂荡响应的叠加效应更为明显;当波高较大时系泊力将由波浪作用控制。更多还原

【Abstract】 In order to study the dynamic characteristics of floating bridges in waves and currents, and to investigate the effects of vehicle velocity, waves and currents on the dynamic properties of the floating bridges,the potential theory is used to calculate the velocity potential around a floating bridge in this paper, and the Morison equation is used to calculate the water resistance of the floating bridge. Besides, the effects of multiaxis moving loads are considered. Then the dynamic motion equation is established in the time domain. The motion responses and mooring forces of the pontoons under different working conditions are calculated. The nonlinear effects of instantaneous wet surface changes on the buoyancy and water resistance of the pontoons are considered in the calculation of the motion equations. The time histories of motion responses and mooring forces of the pontoons under different driving speeds and different wave heights are obtained. The results show that the vehicle velocity has a significant impact on the heave, pitch and mooring forces. The heave,pitch and mooring forces of the upstream lines increase with the increase of the moving velocity, the mooring force peaks of the middle bridge pontoons are smaller than those of both sides of the pontoons, and the motion responses and mooring forces reduced by waves have a certain degree of superposition effect on the motion responses and mooring forces caused by the vehicle loads, especially the heave response. However, the mooring forces will be decided by the waves when the wave height becomes larger.更多还原