针对复合材料力学性能分散度大、加工精度低，导致复合材料薄壁吸能因素不确定等，提出含随机不确定参数复合材料薄壁结构吸能特性评估方法。考虑材料力学性能及结构特征尺寸的不确定性，评估准静态压溃条件下薄壁圆管峰值载荷及比吸能指标。据试样级材料性能实验确定各参数分布特征；用Plackett-Burman方法选实验点，采用显式求解有限元方法分析选出对比吸能、峰值载荷影响显著的参数；建立影响显著参数及结构吸能特性指标间二阶响应面函数；据参数分布抽样计算获得吸能特性指标分布情况。结果显示，对复合材料薄壁圆管而言，纤维方向拉伸、压缩强度及圆管壁厚、基体压缩强度对其轴向压溃的比吸能及峰值载荷影响显著。%Duetothelargedeviationinmaterialpropertiesandinherentmachiningtolerance,uncertainfactors should be considered in designing and evaluating composite energy-absorbing structures.An evaluation method for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters was proposed and developed.Thin-walled composite tubes extensively applied in automobile and aircraft engineerings are typical crushable elements for absorbing collision energy.The uncertainties due to the machining tolerance on the thickness and inner diameter of tube were considered and represented through a probability model.The indices of Triggering Specific Load(TSL)and Specific Energy Absorption (SEA ) were introduced and calculated by finite element analysis for indicating energy-absorbing characteristics of the specimen under quasi-static axial crushing.The Plackett-Burman method was used to choose measurement parameters.The response surface method was then used to build a second-order function of uncertain parameters versus TSL/SEA.The Monte Carlo method was used to obtain the probability of TSL and SEA .The results show that XC,h and XT significantly affect the SEA and XC,h and YC significantly affect the TSL.
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