Optimisation of Hierarchical and Branched Compressionstructures: Determining the Optimal Order for a Paramateriseddesign Scenario

The optimal shape is found for structures that can becharacterised by an order of hierarchy orbranching (examples of such structures include towercranes and the Eiffel tower). The objective is todetermine the circumstances in which higher orderstructures become optimal. It is of specific interestwhether these solutions change when imperfections areincluded. For hierarchical structures, imperfections can existat the local and global scales, and this interactionof imperfections across different ordersof magnitude causes a strength reduction that isgreatest at the optimal shape found byanalysing a perfect structure. It is thereforeessential to include the imperfections within theoptimisation algorithm, because they change theoptimal shape. Branched structures aremore resilient to imperfections at the global scale,so the interaction of imperfections is notas severe.