Accession Number : AD0775732

Title :   Analytical Investigation of Stress Concentrations Due to Holes in Fiber Reinforced Plastic Laminated Plates, Two-Dimensional Models.

Descriptive Note : Final rept. 15 Jan 71-15 Jan 72,


Personal Author(s) : Rybicki,Edmund F. ; Hopper,Allen T.

Report Date : MAR 1972

Pagination or Media Count : 49

Abstract : An equilibrium finite element analysis to obtain stress distributions for anisotropic plates containing a hole is presented. Equilibrium is satisfied exactly by associating a stress function with each element. Stress function representations are such that the number of unknown coefficients per element can vary from element to element. Also the powers of the radial coordinate r in the stress function representation can be distinct for each element. The results of an investigation to determine which powers of r are most appropriate are presented. Solutions to several problems containing high stress gradients are obtained using the method. Numerical results compare very well with reference solutions. Elastic constants for other problems are selected to represent a single boron/epoxy lamina and also various symmetric boron/epoxy lay-ups. An extension of the method to the three-dimensional problem of a laminate containing a hole is described. (Author-PL)

Descriptors :   *Laminated plastics, *Reinforced plastics, Plates, Stress concentration, Holes(Openings), Stresses, Boron, Epoxy resins

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE