Designing bending-active gridshells as falsework for concrete shells through numerical optimization

• A framework is proposed to design a gridshell serving as the falsework for concrete shell. Numerical optimization used fit predetermined target surface under wet loading, taking practical constraints into account. All sensitivities perform gradient-based are derived analytically and validated using finite-differences. The resulting tool small-scale has been constructed tested demonstrate feasibility of suggested system effectiveness approach. Shell structures material efficient capable covering large spans with minimum weight. If building shell, it must be initially supported by formwork. These generally rigid formworks, their supporting structure, time consuming construct. Recently, researchers have recommended use elastic gridshells system. Unfortunately, such complicated deformations bending elements. Moreover, since inherently flexible, significant displacements occur when applying concrete. To overcome these difficulties, this paper presents effectively assumed from an flat grid straight slender rods, cables adjustable lengths brace erected gridshell. An algorithm that fits shape loading given manipulating bracing cables. Meanwhile, reduces construction effort minimizing number cables, diameter rods. ensured constraining axial force in limiting increased loading. scheme adopted, implicit dynamic relaxation approach previously developed specifically simulation bending-active solve nonlinear equilibrium equations. Nonlinear effects buckling rods taken account co-rotational beam applied scale model, demonstrating optimized better, uses less more resistant additional compared designs existing approaches. Comparisons between numerical physical models show deviations up around 2% larger span load smaller loads, differences attributed small model scaling effects.