含缺陷自动铺丝复合材料构件的损伤失效机理研究

For the study of failure mechanism of composite structures with automated fiber placement induced defects, the experimental study will be carried out by using electrical measurement together with the full field non-contact optical measurement. The laminated specimens containing typical defects such as gap,overlap,gap/overlap and twisted tow will be designed and tested. According to the observed phenomenon and experimental data,the analysis model and corresponding algorithm applicable to study the damage evolution behavior and failure mechanism of such structures can be established. For the variable stiffness characteristics of the composite structure fabricated by automated fiber placement process with variable angle ply, the calculation theory and method considering variable stiffness will be developed, and the associated finite element formulation will be derived, and the code for finite element analysis will also be developed. The numerical investigation for the failure mechanism and load-carring ability under static compression based on global-local strategy can be carried out efficiently and some useful results will be obtained for the mechanical properties evaluation of composite structures with automated fiber placement induced defects. In the analysis, the relationship between the global mechanical performance and the local damage behavior will be established as well as the coupling effect between the typical defects and other normal damages.

本项目拟对含缺陷自动铺丝复合材料构件的损伤失效机理和承载能力开展研究，针对含间隙、重叠、间隙/重叠、扭曲波纹四种典型纤维铺放缺陷，开展复合材料板壳的损伤演化行为的实验研究；发展典型缺陷相应的损伤断裂力学理论，建立适用的损伤分析模型来分析其损伤演变规律和失效行为；发展变角度铺设、变刚度层合结构的刚度计算理论，提出相应的有限元分析方法；针对预设不同铺放缺陷形式的加筋板壳结构，开展其屈曲和后屈曲过程中的损伤失效行为和承载能力研究，为含缺陷自动铺丝复合材料构件的力学性能评估提供分析工具。