复合材料波纹梁冲击试验与数值模拟

为了探究复合材料波纹梁的吸能性能,针对铺层形式分别为(±45)3/(0,90)/(±45)3]、(±45)8]和(±45)7]的3种复合材料波纹梁元件,进行了动态冲击试验,得到了吸能载荷-位移曲线,并对其损伤破坏形貌进行了分析。以连续损伤力学为基础,结合改进的Hashin损伤判定准则以及损伤演化规律,提出了针对波纹梁耐撞性损伤分析的刚度退化模型,并基于有限元软件平台开发了适用于波纹梁渐进损伤分析的子程序。对3种不同结构形式的波纹梁进行了渐进失效数值分析,模拟得到了能量评估参数比吸能(SEA)和平均载荷值,并将模拟结果与试验结果进行了对比分析。比较分析了不同薄弱环节复合材料波纹梁的吸能能力。结果表明:波纹梁在冲击载荷作用下发生了渐进压溃失效;平均压溃载荷的相对误差不超过12%,能够满足工程应用要求;薄弱环节的设置需综合考虑复合材料性能和铺层方式等因素。

Impact tests and numerical simulation of composite waved-beam

In order to investigate the energy absorption properties of composite waved-beams, the dynamic impact tests of three types of composite waved-beam specimens which have the stacking sequences of (±45)₃/(0,90)/(±45)₃], (±45)₈] and (±45)₇], were conducted to obtain the energy absorption load-displacement curves and the failure morphology was analyzed subsequently. Based on the continuum damage mechanics, a stiffness degraded model that involved extended Hashin failure criterion and damage evolution law was proposed for analyzing the crashworthiness failure of waved-beams. The progressive failure user subroutine for composite waved-beams was developed on the basis of finite element software platform. The progressive failure numerical analysis was performed for three different types of waved-beams. The energy evaluative parameters including the special energy absorption (SEA) and average load value were acquired by simulation. The simulation and experimental results were compared and analyzed. The energy absorption capability of composite waved-beams with different triggers was compared. The result shows that the progressive crushing failure mode of waved-beam is observed under impact load. The relative error of average crushing load is less than 12%. It satisfies the precision of engineering application. And the property of composites and layup mode should be taken into account for setting the trigger.