CFRP薄壁C型柱轴向压缩破坏机制及吸能特性

为研究碳纤维增强树脂基复合材料（CFRP）薄壁C型柱轴向压缩破坏机制及吸能特性，制备了4种铺层方式、3种厚度组合共12种T700/MTM28 CFRP薄壁C型柱试件。考察C型柱低速轴向压缩过程中的失效模式及载荷变化，通过比较初始峰值载荷、平均压缩载荷、比吸能和载荷效率，分析铺层数及铺层角度对C型柱失效模式及吸能特性的影响。结果表明，纯0°铺层C型柱在轴压载荷作用下发生整体失稳，不具备实际意义上的能量吸收作用；0°/90°铺层、±45°铺层、45°/90°/-45°/0°铺层试件均发生了渐进式破坏，呈现出局部屈曲叠缩的失效模式。其中，45°/90°/-45°/0°铺层的C型柱比吸能随铺层数的增加而增加，具有更大的吸能设计与应用潜力。

Failure mechanism and energy-absorbing characteristics of CFRP thin-walled C-channels subject to axial compression

In order to analyze the failure mechanism and energy-absorbing characteristics of carbon fiber reinforced polymer(CFRP) thin-walled C-channels subject to axial compression, 12 groups of T700/MTM28 CFRP thin-walled C-channels specimens with 3 different layer numbers and 4 different ply orientations were fabricated. The failure modes and load-displacement curves were observed, then the effects of layer number and ply orientation on failure modes and energy-absorbing characteristics were further analyzed by investigating the energy-absorbing characteristics indicator, such as peak load, average load, specific energy absorption, load efficiency. The results show that for specimens with 0° plies, the overall instability occurs so it can not absorb crashing energy. For specimens with 0°/90°, ±45° and 45°/90°/-45°/0°plies, the steady progressive failure and local buckling failure modes are presented. The SEA of C-channel specimens with 45°/90°/-45°/0° plies increases with the layer number increasing and it hence has greater potential for energy-absorbing structure design and application.