中文摘要：

通过介绍扩展有限元的概念及方法,应用ABAQUS有限元分析三点弯曲水泥混凝土梁（I型开裂问题）的开裂过程和不同纤维含量的混凝土开裂行为,并加以对比与评估。通过对水泥混凝土梁裂纹扩展过程和断裂的数值模拟,展示扩展有限元在断裂失效分析方面的独特优势。

英文摘要：

Through introducing the concepts of extend finite element method（XFEM）,applying the finite element method of ABAQUS to analyze the crack propagation of three-point bending concrete beams（Mode I） and the cracking behavior of different fiber reinforced concrete.Finally,the results are compared and evaluated.By the extend finite element numerical simulation for the crack propagation and fracture of concrete,this paper represents the special advantage in term of failure of fracture.