Buckling responses of porous structural components with gradient power-based and sigmoid material variations under different types of compression loads

Abstract

This work developed a comprehensive finite element model and numerical studies to illustrate the effect of porosity parameter on critical buckling responses of functionally graded power-based and sigmoid plates and spherical caps subjected to various types of edge compression loads, for the first time. The model, which follows the kinematics of the first-order-shear deformation theory (FSDT) in many aspects, accounts for a quadratic variation of the transverse shear strains and satisfy the zero condition of the transverse shear stresses at the upper and bottom surfaces of the structure without using shear correction factors. Due to lack of investigations on buckling analysis of porous FGM structures and notably for spherical cap shells, we provide new buckling results for porous FGM structures with evenly and unevenly porosity distributions. The influences of functionally graded index, porosity coefficient, porosity patterns, geometrical design parameters and boundary conditions are investigated and presented in a new graphic manner. The recommended model is helpful for predicting and controlling of the buckling behavior of porous FGM structures used in nuclear and aeronautical sectors where the safety of the engines is a crucial criterion.