Modeling Cumulative Damage Processes in Composite Laminates
Abstract
Procedures for analysis of composite laminates are investigated with a view to modeling cumulative damage. Methods for stress and deformation analysis are examined and new methods necessary to model the behavior are developed. Two approaches, one based on modeling a thin laminate as a two- dimensional body and the other consisting of reducing the three-dimensional problem to a pseudo-two-dimensional one by utilizing the symmetries and the special loading conditions of a free-edge delamination specimen are explored. In the first approach, existing theories of combined bending and stretching of composite laminates based on assumed displacement or assumed stress variation patterns are carefully evaluated in respect of proper two-dimensional approximation of the three-dimensional problem. The existing theories, including the recently developed layerwise or discrete laminate theories are seen to be inadequate in properly allowing for shear deformation and free-edge effects as factors in damage by delamination. A new class of constitutive relationships between force resultants of the individual layers of layers is proposed. Three different a laminate and the deformations of the of stresses in versions, based on different assumptions regarding patterns equilibrium, are investigated.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 27, 1991
- Accession Number
- ADA251534
Entities
People
- R. S. Sandhu
- W. E. Wolfe
Organizations
- Ohio State University