基于损伤指数的三维编织复合材料结构损伤评估

Structural damage evaluation of three-dimensional braided composite based on damage index

以嵌入三维编织复合材料的碳纳米线作为拉伸传感器构建智能复合材料,利用主成分分析(PCA)以及T2和Q统计方法,对三维编织智能复合材料结构损伤进行研究。采用主成分方法对三维编织智能复合材料制件的损伤信息进行处理,以无损伤试件作为基准值建立PCA模型,提出了智能复合材料损伤估计步骤。结果表明:用损伤指数(T2和Q)与基准值的偏差可描述试件结构损伤程度,有损试件的损伤指数远远大于无损试件的基准值,T2损伤指数值可以很好地反映试件较大的损伤,Q损伤指数值较详细地反映了试件的损伤细节;本文方法的计算结果与实际损伤具有很好的吻合性。

The carbon nanotube embedded in the three-dimensional braided composite material were used as stretch sensors to construct intelligent composites. The damage of three-dimensional braided composite material was studied by using principal component analysis（PCA）, and statistical methods of T2 and Q. The method of PCA was used to process the damage information of intelligent 3-D braided composites parts. The specimen without damage was used as a reference value to establish PCA model. The steps of three-dimensional braided composites damage evaluation was proposed. It shows that deviation of damage index （T2 and Q） and the reference value can describe and express the structural damage degree of the specimens. The damage index of damaged sample is far greater than the reference value of sample without damage. Damage index value T2 reflects the large damage of specimens well. Damaged index value Q reflects the damage detail of sample. The results of the method consistent with the actual damage.