An efficient global-local model for thick composite laminates

Abstract

An efficient model based on the recently established partial hybrid stress element is proposed in this paper for global-local analysis of thick composite laminated plates. In this study, for displacement field, the higher order plate theory is used throughout the plate while only the transverse shear stress components are assumed in local regions. Thus, in the region of interest, the flexural stresses ( σ x , σ y , τ xy , σ z ) are still obtained from assumed displacement field while the transverse shear stresses ( τ xz , τ yz ) are calculated by the assumed stress version. The variational principle is also presented in this paper. The proposed functional contains two parts. One is the ordinary potential energy used in the global region; the other is the partial hybrid stress model, which contains displacement and transverse shear as independent variables. The interface equilibrium is guaranteed variationally although no stress parameter is assumed in the global region. Three types of global-local analysis are performed in this paper. These are in-plane analysis, through-thickness analysis, and mixed-type analysis. When compared with elasticity solutions, it is found that the agreement is acceptable, although in the so-called ‘transition region’ the results are less accurate.