Title: Interlaminar Fracture Toughness of Quasibrittle Composites Under Crack-Parallel Tension

Authors: Genki Matsubara, Gaurav Joshi, Marco Salviato

DOI:

Abstract: Recent research challenges the traditional LEFM assumption that crack-parallel stresses have minimal impact on fracture toughness. Gap Test results reveal that in quasibrittle materials, Mode I fracture energy is significantly affected by crack-parallel compression. While compressive stress increases fracture energy up to a point, it eventually leads to a reduction near the material’s compressive strength. In carbon fiber laminates, intra-laminar fracture energy decreases steadily under parallel compression. The Crack Band Model (CBM) effectively captures this behavior, unlike Cohesive Zone Models (CZMs), which fell short to represent the finite-thickness Fracture Process Zone (FPZ). Building on this, we introduce the Half Open I test, a novel method to assess Mode I interlaminar fracture energy under crack-parallel tensile stress. The test uses localized moments at the crack opening to evaluate fracture energy, revealing how tensile stress affects FPZ size and total fracture energy. This new approach corrects previous over/under-estimations in fracture toughness and offers more accurate predictions for the integrity of quasibrittle composite structures.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 159

Pages: 11

Price: $22.00