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

Objectives 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 homo-genization 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.

Conclusions The results of this study can provide valuable references for the design of structures composed of orthogonally stiffened plates.