| Increased emphasis on sustainability and eco-efficiency of material resources for all applications, including structural applications, has motivated exploration of natural fiber composites, or biocomposites. Yet, due to their lower stiffness and strength properties, biocomposites are unable to compete with existing construction materials for load-bearing applications. However, as seen in nature, engineered or optimized designs can lead to improved performance through efficient material and structural configurations. This thesis presents two discrete optimization approaches to obtain optimum material distribution in the cross-sectional layouts of continuous biocomposite cellular panels. The first approach uses a gradient-based sizing optimization method and the second one uses a genetic algorithm to select coupons with finite size features from a pre-defined library. Unlike conventional topology optimization the presented methods enabled optimum hybrid designs. The designs were evaluated through laboratory scale component testing. The optimization results led to layouts that are easier to manufacture than those that can be obtained by traditional topology optimization methods. As expected, the manufactured optimum designs demonstrated improved performance. The material layout optimization methods incorporating finite-size features presented in this study are thus thought to be viable for optimizing material distribution in cross-sections of biocomposite cellular panels and have led to designs feasible for manufacturing. |
