Application of bridging-law concepts to short-fibre composites 4. FEM analysis of notched tensile specimens

This is the fourth paper in a series of four where notch sensitivities, fra cture energies and bridging laws in short-fibre polymer composites are inve stigated. In this paper finite-element modelling (FEM) of centre-hole-notch ed tensile specimens is performed, with different bridging laws governing c rack growth. Crack lengths, crack profiles and stress distributions are pre dicted. The results are compared with experimentally determined crack shape s from an earlier investigation. Only with softening bridging laws can the experimental results be matched. The predicted crack lengths are sensitive to bridging-law parameters. When bridging laws determined by the double can tilever beam (DCB) method are applied, the predicted crack lengths and prof iles show good correlation with the experimental results. The results suppo rt the validity of the DCB method to determine bridging laws in short-fibre composites. (C) 2000 Elsevier Science Ltd. All rights reserved.