A Novel optimization strategy for form-finding and structural stability enhancement of dome-type grid-shell structures

Abstract

Grid-shell structures are prominent in modern architecture and structural engineering, offering efficient solutions for spanning large distances and supporting gravity loads. Among domes, grid shells redistribute materials into lattice members, creating structural depth. Despite their popularity, using structural optimization to find efficient shapes for grid shells remains under-explored. This paper introduces a novel framework to optimize the form-finding process of deep dome-type grid-shell structures using topology and size optimization. Initially, a deep grid-shell structure and load type are defined. An equivalent continuous shell structure undergoes optimization to minimize strain energy and find the optimal grid arrangement. This arrangement is used for size optimization to determine optimal member sizes. Finally, a linear elastic analysis compares the structural performance of the initial gridshell, the topology-optimized continuous shell, and the structural optimization-inspired grid-shell. A case study of a shell subjected to a ring load is presented. Results show significant improvements in material efficiency and structural performance, with optimized designs achieving higher buckling capacities and reduced stresses and displacements. Future work will explore the complexity of topology optimization for shallow versus deep shells and include plastic analyses for large deformations and material yielding, aiming to enhance realistic assessments.