Effect of strain rate on the interlaminar fracture toughness of Zanchor reinforced composites

Abstract

The interlaminar fracture behavior of Zanchor, which is a novel out-of-plane reinforcement technique developed by Mitsubishi Heavy Industries and Shikibo, reinforced composite laminates was studied to clear the mechanism of Zanchor reinforcement, where the effects of loading mode and loading rate on fracture behavior were mainly focused on. The mode I test results showed that the mode I fracture toughness of the Zanchor reinforced composites considerably decreased with increasing loading rate, where the reduction of mode I interlaminar fracture toughness at higher loading rates was a consequence of the loading rate dependence of microscopic fracture behavior. On the other hand, mode II test results showed that the mode II fracture toughness of the Zanchor reinforced composites increased with increasing loading rate, where the reinforcing mechanism of Zanchor under mode II loading was basically different from that under mode I loading.