First Airframe Division, National Aerospace Laboratory(NAL)
First Airframe Division, National Aerospace Laboratory(NAL)
First Airframe Division, National Aerospace Laboratory(NAL)
出版者
航空宇宙技術研究所
出版者(英)
National Aerospace Laboratory(NAL)
雑誌名
航空宇宙技術研究所報告
雑誌名(英)
Technical Report of National Aerospace Laboratory TR-808
Three analytical models for the investigation of the stiffness properties of woven fabric composites are presented in this report. The “mosaic model” is effective for rough prediction of the elastic stiffness of fabric composites. The “crimp model”, which is particularly appropriate for plain weave composites, takes into account fiber continuity and undulation. The “bridging model” is developed to simulate the load transfer among the interlaced regions in satin weave composites. Comparison of theory and experiments is then conducted and leads to a good agreement for 8 harness satin carbon / epoxy composites. In the case of plain weave composites, there exists a great discrepancy between warping constrained and unconstrained predictions. Experimental results fall between these two theoretical curves. Clear dependency of elastic moduli on ply number is found for plain weave. A ratio of ply thickness to thread width is also a very important parameter by which elastic moduli of plain weave systems are strongly affected. In-plane shear modulus of fabric composites is mainly determined by fiber volume fraction which is a function of ng.