Nonlinear impact behaviour of laminated composite shells in hygrothermal environments

Abstract

The nonlinear transient response of laminated composite shell panels subjected to low velocity impact in hygrothermal environments is investigated using finite element method. The present formulation considers doubly curved thick shells and includes large deformations with Green- Lagrange strains. The analysis is carried out using quadratic eight—noded isoparametric element. A modified Hertzian contact law is incorporated into the finite element program to evaluate the impact force. The nonlinear equation is solved using the Newmark average acceleration method in conjunction with an incremental modified Newton-Raphson scheme. The validity of the present analysis is demonstrated by comparing the present results with the solutions available in the literature. A parametric study is carried out to investigate the effects of the curvature and side to thickness ratios of simply supported composite cylindrical and spherical shell panels.