Numerical Simulation of Steel Fiber's Crack Resistance on Cement-based Composites

In this paper, the cement base and steel fiber are modeled separately through a separate model. The cement base uses a concrete damage plastic model; while the steel fiber imports the programmed program into the simulation software to generate randomly distributed steel fibers, and the steel fiber uses a truss unit. After the separation model is modeled, it is combined with the extended finite element to simulate the cracks of the steel fiber reinforced cement-based beam with I-shaped notch under the action of three-point bending, and the crack propagation until the cement-based beam is completely broken. According to the simulation results, the load-deflection and load-crack opening displacement curves of the cement base were drawn; the crack evolution process was tracked; various fracture parameters were calculated; and the stress time history curves of the steel fibers in different regions were drawn. The results show that: steel fiber can effectively improve the fracture energy and fracture toughness of the cement base, and play a toughening and crack resistance effect on the cement base; the crack resistance of steel fiber is mainly produced by the steel fiber in the middle span and the crack area. The steel fibers at both ends of the beam have little effect on the cement base.