Fracture toughness measurement of curved fiber reinforced composites; experimental approach

Abstract--- In the present research, the effect of curved shape on delamination toughness of composite beams, reinforced by woven glass fibres has been investigated experimentally. Double cantilever beam (DCB) test was used to asses fracture in mode-I loading. Specimens were made of woven glass fibres and epoxy matrix with similar geometry but different initial crack lengths. Modified beam theory and compliance calibration method (CCM) have been used as data reductions to evaluate critical strain energy release rate (SERR). A new formulation for calculating (SERR) based on beam theory that includes the effects of curved shape has been proposed. Results show that given procedures in calculating (SERR) were suitable for evaluating fracture energy in laminated curved beams; since the measured fracture toughness values illustrate low crack length dependency. Keywords – , ,