High rate damage of composite material for modelling of energy absorbing structures

Abstract

This paper proposes an approach for the modeling of crushing behavior of absorbing structural components, made of fiber-reinforced composite material. The effect of strain rate dependency of material properties is in the focus of this research, thus proposed material model is based on introduction of damage parameters, and high rate behavior is expressed in terms of damage rate. Stress-strain response of typical carbon fiber-reinforced composite to a wide range of impact loading rates provides data for calibration of the proposed model. Abaqus explicit solver with implemented user material model is used for direct 3D finite element simulation of impact with tubular specimen. Impact initiation process is considered in details to explain initial peak appearance on load diagram not only caused by the tube chamfer failure with consequent transfer of crushing process to a regular tubular zone, but also as effect of strain-rate dependency. Simulation shows a good agreement with typical load-displacement curves and crashworthiness values.