Analysis and design of laminated composite beams based on a refined higher-order theory

In this work, a new analysis and design methodology of laminated composite beams is presented. The problem is formulated for both symmetric and antisymmetric ply-stacking configurations, based on a refined higher-order shear deformation theory. The solution is obtained using the Analog Equation Method (AEM) while the design process is based on the Differential Evolution (DE) metaheuristic optimization algorithm, using both displacement and strength-related objective functions. Numerical examples are presented, demonstrating the applicability and effectiveness of the proposed analysis and design methodology. The results indicate that to minimize the deflection of an orthotropic laminated beam the principal material orientation must coincide with the longitudinal axis of the beam. Moreover, for the strength optimization problem, the Tsai-Wu failure criterion proved to be numerically unstable, returning very large negative values for seemingly indifferent configurations. Conversely, Hashin's criterion manifests robustness during the optimization process ensuring efficacious design.