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,


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

PDF Url : ADA139998

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

Distribution Statement : APPROVED FOR PUBLIC RELEASE