Computational Study for Size Effect in Composites and Nanocomposites

Abstract

An extensive parametric study sweeping both material and geometrical parameters is performed using size effect law (SEL) and Cohesive Zone Modeling (CZM). These simulations and recent experimental results suggest that the cohesive law of composites and nanocomposites is bi-linear and that the Fracture Process Zone (FPZ) may be almost fully developed already for laboratory-sized specimens. As a consequence, the scaling of the fracturing behavior may be influenced significantly by not only the total fracture energy but also the parameters describing the shape of the bi-linear cohesive law. The goal of this work is to formulate a master size effect curve that can be used for quick, yet accurate, estimation of energy and cohesive law parameters that can be used for the design of composite aircraft structures.