Practical realization of fatigue crack propagation simulations using the extended finite element method(X-FEM)

开发了基于扩展有限元法（XFEM）公式的应力分析程序。在规范中，通过Heaviside阶跃函数和渐近基函数丰富了传统有限元分析中使用的实体单元和壳单元，从而可以独立于有限元对裂纹几何进行建模。此外，通过控制所开发的XFEM代码的执行，可以很容易地进行裂纹扩展分析。将这些规范应用于金属和复合材料结构的裂纹和疲劳裂纹扩展分析，得到了适当的结果。

Stress analysis codes based on the formulation of the extended finite element method(XFEM) have been developed. In the codes, solid and shell elements utilized in conventional finite element analyses are enriched through the Heaviside step function and the asymptotic basis functions, and consequently the crack geometry can be modeled independently of the finite elements. Moreover, crack propagation analyses can be performed easily by controlling execution of the developed XFEM codes. The codes were applied to crack and fatigue crack propagation analyses of metal and composite structures, and appropriate results were obtained.