Computational Modeling of Damage Extension Ahead of Notch Tip in Fiber-Reinforced Composites

Abstract

Considerable effort has thus far been made for the computational modeling of the Mode I type progressive fracture of notched composites (for example, Ref. [1–6]). The modeling can be classified broadly into two kinds. One is the modeling based on the stiffness degradation model[1-3] and another the fictitious crack model[4–6]. In the stiffness degradation model, stress and strain distributions inside the composites are firstly calculated by the use of a finite element method (FEM). By the use of the results, failure of the composites is examined on the basis of failure criteria, and reduction of mechanical properties is evaluated. In the fictitious crack model, the damage developed at the notch tip is modeled as a fictitious crack with the cohesive stress acting on the crack surfaces. The relationship between the cohesive stress and crack opening displacement, i.e., the tension-softening relation, is determined theoretically or experimentally.