Finite element modelling of bridging micro-mechanics in through-thickness reinforced composite laminates

The basic objective of this research project was to develop an efficient and accurate finite-element-based numerical tool to simulate the spontaneous propagation of a single TTR pull-out under quasi-static conditions and in the presence of frictional contact between the fiber/matrix interface. The pull-out phenomenon was studied assuming a constant friction coefficient at the interface along the TTR axial direction and using improved contact-elements to solve the frictional contact problem. Load/displacement bridging curves of the fiber pull-out process, which includes elastic deformation with a fully/partially bonded interface plus frictional sliding, were calculated. Moreover, the effect of friction model was also investigated. Numerical results were validated by experimental observations of debonding and frictional sliding of a fiber in steady-state pull-out tests under pure Mode I loading conditions.