Multiscale modelling of CFRP composites exposed to thermo-mechanical loading from fire

Carbon fibre reinforced polymers (CFRP) are susceptible to structural damage during extreme events such as fire. Typically, modelling the effects of fire on CFRP structures is carried out by mesoscale analysis to predict the overall structural performance. In this work, Finite Element (FE) modelling has been undertaken to understand the effect of fire on CFRP specimens, at both meso- and micro-scales. The models herein use mesoscale analysis to inform microscale analysis to study the effects of fire on each constituent. A comparison of thermal analysis at mesoscale and microscale indicates a less than 6% difference in the predicted node temperature. Fire-induced progressive failure analysis, for the first time, was conducted on the fibres, matrix and fibre/matrix interface of representative plies within the composite laminates. Fibre breakage, matrix cracking and interface debonding were well captured with representative volume element models (RVEs) under thermo-mechanical loading with qualitatively excellent agreement with experimental data.