Fatigue of Laminated Composite Structures
Abstract
The purpose of the work supported by this contract was to investigate the mechanisms of fatigue in fibrous metal matrix composites and laminates. The approach to the problem was based on two simultaneous research efforts. In the theoretical part of the program, the elastic-plastic behavior of unidirectional and laminated composites was described with the help of the Vanishing Fiber Diameter (VFD) model. The model simplifies the geometry of the microstructure by assuming that each of the reinforcing fibers has a vanishingly small diameter and that the fibers occupy a finite volume fraction of the composite. Thus the strain fields in both fiber and matrix are uniform. Overall constitutive equations of the elastic-plastic composite aggregate were derived from the properties of the constituents, their volume fractions, and geometry of the microstructure. The theory was extended to the case of in-plane mechanical loading of symmetric laminated plates. Also, a finite element code for three-dimensional analysis of elastic-plastic composite structures was developed and used in selected applications, which included investigations of stress fields at circular holes and cracks in laminated plates. Shakedown limits of certain laminated plates used in the experiments were also established. Work was started on analysis of distributed fracturing in unidirectional composites.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1982
- Accession Number
- ADA117731
Entities
People
- George J. Dvorak
Organizations
- University of Utah