A micromechanical model for the creep behavior of fiber composites is de veloped based on a typical cell consisting of a fiber and the surrounding matrix. The fiber is assumed to be linearly elastic and the matrix nonlinearly viscous. The creep strain rate in the matrix is assumed to be a function of stress. The nominal stress-strain relations are derived in the form of differential equations which are solved numerically for off-axis specimens under uniaxial loading. A potential function and the associated effective stress and effective creep strain rates are introduced to simplify the orthotropic relations.
References
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2.
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3.
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4.
Dan Jumbo, E.A., B.C. Harbert and R.A. Schapery "Constant Rate, Creep Behavior and the Analysis of Thermoplastic Composite Laminates," presented at the ASTM 9th Symposium on Composite Materials Testing & Design, Reno, Nevada (April 27-29, 1988)
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6.
Sun, C.T. and J.L. Chen "A Simple Flow Rule for Characterizing Nonlinear Behavior of Fiber Composites," Proceedings of the Sixth International Conference on Composite Materials, Imperial College, London , England, pp 1250-1259 (July 20-25, 1987)
