Phase field method for simulating the brittle fracture of fiber reinforced composites

We implemented a three-dimensional phase field model to simulate crack initiation and propagation in fiber reinforced composites. An efficient and robust staggered scheme is adopted by decoupling the fracturing phase field and displacement field. With this approach, the mixed-mode crack propagation in composite materials as well as the fracture process of fiber reinforced composites can be precisely captured. Our results revealed that the mechanical properties and crack propagation are influenced by the direction of inside imperfection with respect to load, interactive effects of the imperfections and damageable layer impact. We observed that accurate post-peak displacements and sharper crack evolution can be obtained by employing smaller displacement increments. The present model precisely captured the physical-consistent phenomena that crack initiates from a damageable layer, followed by matrix cracking, crack branches when it encounters a stiffer material and propagates along the interface, and interactive crack growth.