Delamination initiation and migration modeling in clamped tapered laminated beam specimens under static loading

Abstract

The Clamped Tapered Beam Specimen (CTBS) designed to study the initiation of matrix cracking and delamination and their propagation including delamination migration from one interface to another was considered. Regularized eXtended Finite Element Method (Rx-FEM), which allows modeling the matrix cracking in a direction independent of finite element boundaries, was used for the analyses. The key parameters which were compared with the data obtained during the simultaneously conducted experimental program included peak loads, matrix crack initiation locations and delamination migration locations. The predicted peak loads were within the experimental range when high transverse strength values obtained from three point bend tests were used in the predictions. The matrix crack initiation location as well as delamination migration locations were correctly predicted by taking into account residual thermal stresses and implementing energy dissipation based load control algorithms to model delamination migration during unstable crack propagation.