Parametric investigation of vibration of stiffened structural steel plates using finite element analysis and grey relational analysis

Thin plates with arbitrary shapes and stiffeners find wide usage in construction, aerospace, marine, etc. industries. In the present work a parametric investigation of thin structural steel plates has been carried out. The design parameters considered were the subtended angle and aspect ratio of plates to account for the different shapes of plates used for various applications. Another design parameter that was considered is the stiffener and its different orientation. The impact of varying parameters on the first five modal frequencies and in turn the stiffness was considered as the response. Finite element method (FEM) coupled with Taguchi’s L16 orthogonal array and grey relational analysis was used to maximize the first five natural frequencies simultaneously. The thin plate was subjected to modal analysis when all its sides are in simply supported boundary condition. The optimum combination of design variables predicted by grey relational analysis is a thin plate with 80° subtended angle, 1.75:1 aspect ratio and crossed stiffener orientation for simultaneous maximization of the frequencies. Analysis of variance revealed highest contribution of stiffener type which affects the f