Automatic generation of random distribution of fibers in long-fiber-reinforced composites and mesomechanical simulation

An algorithm for the automatic generation of 2D representative volume element (RVE) of unidirectional long-fiber-reinforced composites (LFRCs) is presented in this paper. Both high fiber volume fraction and random fiber distribution are considered in the RVE. Two procedures which are named as global crisscrossing and local disturbing are included in this algorithm. Based on the model generated, mesomechanical analysis is carried out by using general finite element method (FEM) software ABAQUS. Firstly, the effect of the randomness of fiber distribution on the transverse modulus is investigated. Secondly, user subroutine to redefine field variables at a material point (USDFLD) in ABAQUS is used to simulate the damage behavior. A series of computational experiments are performed to evaluate the influence of mesh size on the ultimate load of the composites. The obtained results prove that the algorithm is capable of capturing the random distribution nature of these materials and the RVE produced could be used for predicting the damage onset and propagation of LFRCs.