Nonlinear free oscillation of tri-directional functionally graded porous skew-plates with variable thickness in high-thermal environment
Hong Hieu Le, Van Ke Tran, Nhan Thinh Hoang, Thanh Tran
Abstract
For the first time, a finite element model was constructed based on the improved shear deformation plate theory and the von Kármán assumption to analyze the linear and nonlinear free vibration behaviour of tri-directional functionally graded porous (TFGP) skew-plates with variable thickness resting on variable Pasternak-elastic foundation in high-temperature environments. The primary goal is to support advanced engineering structures' analysis, design, and manufacturing processes by understanding their nonlinear behavior under thermal conditions. The novelty of this research is the use of materials with mechanical properties that vary in all three directions in space with the thickness of the plate changing non-linearly in two directions in the horizontal plane. In high-temperature environment, not only the mechanical properties of the material are degraded, it also causes thermal stiffness matrix which reduces the overall stiffness of the structure. The model's accuracy and efficiency are validated through comparisons with existing solutions. To comprehend how different components affect the nonlinear free vibration characteristics under various situations, extensive parametric analyses are carried out. The results of this study can be used in the design calculations of structures subjected to large deformations in practice such as defense, construction, and aerospace.