Multi-parameter optimization of lightweight composite triangular truss structure based on response surface methodology

Abstract

A multi-parameter optimization approach for a lightweight FRP composite triangular truss under nonlinear structural response constraints is presented in this paper. The composite truss exhibited bilinear behavior under three-point bending which was observed by both experimental and numerical investigation. Sensitivity analysis was conducted to evaluate the effects of geometric parameters on the flexural performance of the composite truss. A response surface, developed from a finite element analysis, was employed to replicate the outputs of nonlinear structural responses with respect to four key geometric parameters. Gradient-based and Genetic Algorithm optimization processes were selected and implemented from the MATLAB Optimization Toolbox. Final adjustments to the optimal design, obtained using MATLAB, were made according to the results of sensitivity analysis. The results show that significant improvement in terms of weight saving were achieved by adopting the proposed optimization design procedure.