Assessment of the Fracture Behavior of an Asymmetrically Loaded Cantilever Composite Structure

Abstract

The complex fracture behavior of a cross-ply composite cantilever beam with artificially embedded delamination is investigated analytically, numerically, and experimentally. The analysis of the cantilever beam is divided into two geometric configurations: the global bending of the undelaminated cantilever, and the local buckling of the delaminated part. A finite element model developed in ANSYS is used to concurrently analyze the effects of contact zone and delamination in the aforementioned asymmetrically loaded structure. The obtained experimental data are correlated and compared with the findings of the FEM simulations. All numerical, analytical, and experimental results illustrate that the fracture behavior of the laminate cantilever beam is dominated by mode II, mainly due to the effect of a large contact zone. The latter is determined by geometric and loading parameters. The dominance of mode II over mode I, leads to the initiation and propagation of an interfacial crack rather than an intralayer one. Furthermore, experimental evidence indicates that crack kinking during propagation depends on the architecture of the specimens.