非正交加筋对加筋板动刚度的强化作用与均化效应

Reinforcement and homogenization of non-orthogonality stiffening on dynamic stiffness of stiffened plates

[目的]为开展船舶与海洋工程典型板架结构设计与优化,需探究不同加筋形式对加筋板动力特性的影响。[方法]采用有限元法计算四边固支边界条件下正交加筋板、倾斜加筋板、弯曲加筋板等模型的固有频率与振型,并对比分析这3种加筋板动力特性的区别与联系,从而揭示加筋形式对板-梁动力耦合特性及加筋板本征动力特性的影响规律。[结果]对比结果表明,倾斜加筋板的固有频率比正交加筋板增加了9%;相较于正交加筋板,倾斜加筋板和弯曲加筋板的动刚度分布更均匀,其中弯曲加筋板的动刚度均化效应更显著;当频率较低时(低于900 Hz),加强筋的主导程度越高,加筋形式对加筋板动力特性的影响越大。[结论]研究成果可为船舶加筋板的结构设计提供参考。

[Objective]In order to design and optimize the typical orthogonally stiffened plates commonly used in naval architecture and ocean engineering,it is necessary to investigate the influence of different stiffener configurations on the intrinsic dynamic characteristics of orthogonally stiffened plates.[Methods]The natural frequencies and mode shapes of orthogonally,obliquely and curvilinearly stiffened plates are calculated using the finite element method under clamped boundary conditions.Comparative and analogy analyses of the intrinsic dynamic characteristics of the three types of stiffened plates reveals the influence of stiffener configurations on their dynamic coupling behavior and intrinsic dynamic characteristics.[Results]The numerical results show that the natural frequency of obliquely stiffened plates can be increased by 9%compared to that of orthogonally stiffened plates,while the stiffness distributions of obliquely stiffened plates and curvilinearly stiffened plates are more homogeneous than that of orthogonally stiffened plates,and the dynamic stiffness homogenization effect of curvilinearly stiffened plates is more significant.In the frequency range below 900 Hz,the stronger the reinforcement,the greater the influence of the stiffener configuration on the dynamic characteristics of stiffened plates.[Conclusion]The results of this study can provide valuable references for the design of structures composed of orthogonally stiffened plates.