Robust form finding of tree-like structure by improved slime mould algorithm

To achieve a robust and efficient form finding design for tree-like structures, this study proposes an innovative form finding approach based on an improved slime mould algorithm. This method leverages the loads and coordinates of each support joint within the tree-like structure as initial conditions and defines the solution space according to the structural configuration, aiming to minimize the bending moments at the joints. To circumvent freezing problems during iterations, the improved slime mould algorithm is deployed to iteratively determine joint positions at each hierarchical level, starting from top and moving downward, thereby accomplishing the overall form finding for the tree-like structure. After the form is established, the cross-sectional dimensions of the structure are optimized for weight reduction while ensuring that the design meets a variety of performance criteria. As a case study, the tree-like structural columns in Dalian Jinzhou Bay Airport are used to demonstrate the specific implementation procedures of form finding and section optimization. A comparative analysis is performed between the optimized design and the original structure. The research findings reveal that, in comparison to the initial structure, the optimized structure experienced a 27.7 % reduction in maximum combined stress, a 1.8 % decrease in total deformation, a 22.1 % reduction in mass, and an enhancement in stability. These results confirm the effectiveness of the improved slime mould algorithm in tree-like structure form finding and section optimization and adding a section optimization stage makes the optimization process of the tree-like structure more complete, thereby avoiding the phenomenon of excessive self-weight after form finding and making the optimization results more reasonable.