为了对表面损伤的CNG-Ⅱ复合材料气瓶进行安全评价，从理论分析、数值分析及疲劳裂纹扩展三个方面对复合材料损伤的典型研究进行总结。对相关理论进行分析与比较，得出应从损伤区的应力分布出发，利用有限元软件模拟计算出损伤区周围的应力场及裂纹尖端应力强度因子，通过复合材料的Tsai-Wu强度理论以及W-N剩余强度预计模型的相关断裂准则得出复合材料层失效的临界裂纹尺寸，最后利用疲劳裂纹扩展中裂纹扩展速率da/dN与应力强度因子变化范围ΔK的关系式，经过迭代求得裂纹从一定初始尺寸扩展到临界尺寸所需要的循环次数的结论。%Typical researches about composite′s surface damage were introduced from the relevant theoret-ical analysis,numerical analysis and fatigue crack growth to evaluate the security of CNG-Ⅱ composite cylinder which with surface crack or damage and the relevant theories were compared.It was concluded that it should focus on the stresses distributed in damage zone and use the finite element software to simu-late the specific circumstances of stress distribution.It can be used for Tsai-Wu strength theory of com-posite materials and relevant fracture criterion of W-N residual strength model to analysis the damage tolerance to the surface damage on the CNG-Ⅱcomposite cylinder′s winding layer.At the end,it can be used for the relationship of crack growth rate da/dN and stress intensity factor range ΔK to gain the num-ber of cycles which needed from a initial crack size to the critical size by iterative algorithm.
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