Elastic-Plastic Stress Analysis in a Unidirectionally Reinforced Composite Cantilever Beam Loaded by a Bending Moment

Abstract

In this study, an elastic-plastic stress analysis is carried out on a steel fiber thermoplastic composite cantilever beam loaded by a bending moment at the free end. The composite beam is reinforced unidirectionally at 0, 30, 45, 60 and 90° orientation angles. An analytical solution satisfying both the governing differential equation and the boundary conditions for the two-dimensional stress case is determined. The solution is carried out under the assumption of the Bernoulli-Navier hypotheses. It is found that the intensity of the residual stress component of σ_x is maximum at the upper and lower surfaces or at the boundary of the elastic and plastic regions. The composite material is assumed to be hardening linearly. The Tsai-Hill theory is used as the yield criterion.

Keywords

thermoplastic composite beam elastic-plastic analysis residual stress reinforced composite

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