Accession Number : ADA139998


Title :   Analysis of Symmetric Reinforcement of Quasi-Isotropic Graphite-Epoxy Plates with a Circular Cutout under Uniaxial Tensile Loading.


Descriptive Note : Master's thesis,


Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA


Personal Author(s) : Pickett,D H ; Sullivan,P


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a139998.pdf


Report Date : Dec 1983


Pagination or Media Count : 112


Abstract : An experimental and computational analysis was made of the strain field around a reinforced circular hole in four HMF330/34 graphite/epoxy (G/Ep) panels under uniaxial tensile loading. The basic panel was a 10.0 in. wide, 26.0 in. long, eight ply, quasi-isotropic (0/+45/90)s cloth laminate. Each panel was reinforced during manufacture by co-curing two circular plies of the same material to each side of the panel. A circular one inch hole was drilled concentrically through the laminate to provide a stress concentration. The symmetric reinforcement reported here provided an improvement of 29 to 40% in ultimate strength over a similar but unreinforced panel under the same loading conditions. Test results indicated that panel failure would occur when the fibers in the dominating orientation were strained approximately 1%. There appeared to be a significant load transfer within the laminate at high strains from the failed fibers. A finite element analysis was made and found in excellent agreement with experimental results.


Descriptors :   *Composite materials , *Graphited materials , *Epoxy compounds , *Strain(Mechanics) , *Finite element analysis , Stress concentration , Fiber reinforcement , Fabrics , Laminates , Symmetry , Failure(Mechanics) , Tensile properties , Loads(Forces) , Stresses , Fracture(Mechanics) , Elastic properties , Strain gages , Naval research , Research management , Theses


Subject Categories : Laminates and Composite Materials
      Numerical Mathematics
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE