Simulation of progressive failure in laminated composites under variable environmental conditions
Ganapathi Ammasai Sengodan, Giuliano Allegri, Stephen R. Hallett
Abstract
This paper presents the development, calibration and finite element implementation of a novel set of phenomenological equations describing the effect of temperature and moisture on the stiffness, strength and toughness properties of fibre-reinforced plastics. An extension of the classical Zhurkov's kinetic approach is proposed to describe the effect of temperature and moisture on the ply-level matrix-dominated strength properties. The phenomenological equations are implemented into a finite-element simulation framework, consisting of a smeared crack approach for modelling intralaminar and translaminar failure, coupled with a bi-linear cohesive zone approach to describe delamination onset and progressive growth. The modelling approach is calibrated by means of experimental data in the open literature for the carbon-epoxy material IM7/8552. Validation case studies for the simulation strategy include quasi-isotropic short beam shear coupons and open-hole specimens subject to tension. It is demonstrated that the proposed simulation framework provides a comprehensive quantitative description of the role played by environmental effects in terms of development and interaction of intralaminar, interlaminar and translaminar damage processes.