Numerical Simulation to Evaluate Fatigue Fracture Behavior of Concrete Beam with Initial Crack

In order to evaluate the fracture toughness of concrete, this article has employed extended finite element method (XFEM) to predict the maximal fracture loading of three-point bending beam with initial notch. The result of numerical test has manifested the limited loading is about 57 KN, which would induce the directed fracture over cross concrete beam. When the loading magnitude is about 0.5 times of the limited loading, a shakedown situation would happen, and the concrete would not occur unsteadily and ultimate fracture under this loading conditions.