Dynamic Fracture Simulation of Functionally Graded Engineered Cementitious Composite Structures Based on Peridynamics

In this paper, a semi-discrete model based on peridynamics (PD) for engineered cementitious composites (ECCs) is applied to simulate the fracture behavior of functionally graded ECC (FGECC) beams. This is a new application of PD in ECC. Prior to simulating the crack behavior, the convergence of the PD model for ECC is discussed and the appropriate horizon size delta and nonlocal ratio m are obtained, i.e., delta = 1.6 nun and m = 4. In addition, when the bond strain exceeds the elastic limit, delta damage variable is introduced into the model, and the model is validated using a simple numerical algorithm. Finally, the dynamic fracture behavior of a two-dimensional FGECC beam under four-point bending is investigated, and the effect of the initial crack location on the fracture behavior is analyzed. Simulation results show that the initial crack location can affect the crack propagation pattern, thereby enabling one to understand the dynamic fracture behavior of ECC structures and guide the engineering practice.