7500t浮吊海浪激励下的谐响应分析

应用有限元软件ANSYS建立500t浮吊三维计算模型，以规则海浪载荷作用下船舶摇荡运动加速度作为基础激励，采用谐响应分析方法计算起吊7500t载荷时浮吊在海浪作用下的动力响应。计算结果表明，海浪方向为90°时浮吊动力响应比较大；吊重起升至比较高位置时，浮吊动力响应比较大；因船舶横摇大于纵摇，故浮吊的横向位移大于纵向和垂向位移，钢丝绳吊重横向摆角大于纵向摆角；臂架的最大动应力出现在根部主弦杆处，海浪载荷引起的浮吊结构动应力小于材料屈服强度。

The Harmonic Response Analysis of 7500t Floating Crane under the Excitation o{ Sea Waves

A 3-D model was established for a 7500t floating crane in ANSYS. The dynamic responses of the floating crane were calculated using the harmonic analysis method due to the excitation of vessel＇s motion caused by the wave in the sea. Calculation results showed that the dynamic responses of the floating crane are large when the wave travels in 90° towards the vessel. When the position of the lifted load is high, the dynamic responses of the floating crane are large. As the amplitude of rocking is larger than that of pitching of the vessel, the lateral displacement response of the floating crane is larger than the longitudinal one, and the rope-load system swings larger in the lateral direction than in the back-forward direction. The largest dynamic stress appears at the bottom of the jib of the crane and it is below the yield limit of material.