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基于连续介质损伤力学,提出了一种包括层内和层间失效的非线性渐进损伤模型来预测复合材料波纹梁在轴向冲击下的失效行为。其中,层内损伤采用最大应力准则,并结合指数型损伤演化法则和刚度折减方法预测失效后的材料参数。层间损伤模型则采用了二次名义应力准则、基于混合模式能量的指数型损伤演化法则和黏性刚度折减方法建立。基于该模型,对典型的波纹梁结构参数和触发等对耐撞性的影响进行了研究。结果表明数值模拟结果与试验结果基本吻合,模型能够准确地模拟复合材料波纹梁在冲击过程中出现的分层、纤维和基体破坏等失效模式。波纹梁在破坏过程中吸收的能量、比吸能和载荷峰值随层数不断递增,降低高度和减小触发结构的截面面积均会降低载荷峰值。
Based on the continuum damage mechanics, a nonlinear progressive damage model including in-layer and inter-layer failure is proposed to predict the failure behavior of composite corrugated beams under axial impact. Among them, the maximum stress criterion is adopted for the intralayer damage, and the material parameters after the failure are predicted by combining the exponential damage evolution law and the stiffness reduction method. The interlayer damage model uses the second-order nominal stress criterion, the exponential damage evolution law based on the mixed-mode energy, and the viscosity stiffness reduction method. Based on this model, the influence of structural parameters and triggering on the crashworthiness of typical corrugated beam was studied. The results show that the numerical simulation results are in good agreement with the experimental results. The model can accurately simulate failure modes such as delamination, failure of fiber and matrix in the impact process of corrugated composite beams. The energy, specific energy absorption and peak load of corrugated beam during destruc- tion increase with the number of layers. Decreasing the height and decreasing the cross-sectional area of the trigger structure will reduce the peak load.