铺层顺序对复合材料薄壁圆管轴向压溃吸能特性的影响研究

采用仿真和试验相结合的方法探讨复合材料薄壁圆管在准静态轴向压缩载荷下的失效吸能特性和吸能机理。首先，建立复合材料薄壁圆管"层合壳"有限元模型，通过显式动力学方法求解其在准静态轴向载荷下的压溃失效力学行为。仿真与试验结果在圆管轴向压溃变形过程、初始峰值载荷、平均压溃载荷及比吸能等主要吸能参数上具有很好的一致性，验证了"层合壳"复合材料圆管有限元模型和建模方法的有效性。其次，采用解析模型与仿真分析方法分别对0/90]_3s、0/90/0₂/90₂]_s、0₃/90₃]_s三种不同铺层顺序的复合材料圆管的屈曲载荷与吸能特性进行了对比，进一步分析了铺层顺序对圆管失效吸能特性的影响。研究表明，0°与90°铺层交替程度对复合材料圆管的吸能特性影响较大，保证纤维失效方式在结构宏观失效中占主导地位能够提高材料失效吸收能量。

INFLUENCE OF LAYER SEQUENCE ON ENERGY ABSORPTION CHARACTERISTICS OF THIN-WALLED COMPOSITE CIRCULAR TUBES UNDER AXIAL COMPRESSION

The paper aims to investigate the crashworthy behavior of composite thin-walled circular tubes under axial compression. Load-displacement curves and energy absorption characteristics were obtained under quasi-static axial crushing tests. A stacked shell model of the composite circular tubes was built by using explicit finite element software PAM-CRASH. Compared with the experimental results, the axial deformation process, initial peak load, mean crushing load and specific energy absorption of composite circular tube were analyzed to validate the finite element model and modeling approach of composite circular tubes. Based on the validated model, composite circular tubes of different layer sequences0/90]_3s,0/90/0₂/90₂]_s,0₃/90₃]_s were studied by numerical simulation. Through the comparison of the theoretical value of buckling load and energy absorption characteristics, the influence of layer sequences on energy absorption characteristics of composite circular tubes were analyzed. The results show that the layer alternation of 0° and 90° has a great influence on the energy absorption characteristics of composite thin-walled circular tubes and it is possible to improve the energy absorption of the material by ensuring that the fiber failure mode dominates the structural failure.