中文摘要：

为研究复合材料身管的疲劳裂纹扩展问题,基于线弹性破坏力学的扩展有限元法,采用非线性有限元软件ABAQUS,建立了含微缺陷复合材料身管的简化模型,对内压冲击载荷循环作用下的疲劳裂纹扩展进行了仿真计算。结果表明：随着循环数的增加,疲劳损伤能耗不断增大,材料性能不断退化;同等载荷循环和边界条件作用下,不同位置的起始裂纹均沿着轴向和径向扩展,沿径向的扩展速度大于沿轴向的扩展速度,起始裂纹位于两端要比位于中间对复合材料层造成的破坏严重,后者的承载能力更强。

英文摘要：

To study the fatigue crack growth of composite barrel, based on the principles of linear elastic fracture mechanics（LEFM） and extended finite element method（XFEM）,composite barrel with preexisting crack were modeled to predict the development of the crack during loadingunloading loops. The material model was implemented into ABAQUS standard finite element code,and the law of its fatigue crack growth was concluded. With the increase of the cycles,the fatigue damage energy-dissipation grows stably, and the material properties gradually deteriorate. The initiate crack at different positions of the composite tube extend along both of the axis and the radial direction with the same load cycles and boundary conditions, and the velocity along the radial direction is larger than that along the axis direction. The fatigue damage caused by the initiate crack at the ends is more intense than that in the middle position, and the carrying capacity of the latter is better.