Geometric and structural optimization of concrete shells

Abstract The thickness distribution in continua concrete shells is a key factor in minimizing the volume of material required for the construction of these distinctive structures, with a significant impact on both sustainability and economic costs. In this study, second‐degree functions are used to approximate and optimize the thickness distribution of continua concrete shells. Three distribution parameters are considered: (i) the thickness at the center; (ii) the thickness at the support; and (iii) the thickness at the middle of the free border. The ideal solution is defined as achieving a uniform stress distribution across the shell, referred to as the “target stress.” The residual error (calculated as the difference between the actual stress and the target stress) and final material volume are used to compare results obtained for different shape configurations. The shape of the shell's middle surface is also optimized, with the distribution parameters being updated iteratively at each step of the membrane form‐finding process. The adopted optimization methods produced good results, namely more efficient structural behavior and reduced material consumption. While the developed methodology was applied to a concrete shell in this study, its broader application is evident; it can be applied to any type of shell that is partially supported along its boundary and has a rotational symmetry axis.