| dc.description.abstract | This thesis tackles the design of freeform surface-like and load-bearing structures
realized with cladding panels and supported by a framework substructure,
often called gridshells. The actual fabrication of freeform gridshells is
a challenging task, and easily leads to unsustainable costs. A well known
strategy to realize a gridshell is to use as layout a so-called principal mesh.
This is a quadrilateral mesh whose edges follow the principal curvature directions
of a continuous surface. We achieve in this way flat cladding panels
and a substructure with simplified connections.
This thesis shows that quadrilateral meshes, besides allowing manufacturing
simplification, are also optimal solutions both for static performance
and smooth visual appearance. In particular, we show that the best static
performance is achieved for quad meshes discretizing membranes along principal
stress lines, and we get an absolute minimum on such membranes where
the integral of absolute principal stresses is minimal. We also show that the
best smooth visual appearance is achieved for principal meshes; the absolute
minimum is now reached for principal meshes discretizing surfaces where the
integral of absolute principal curvatures is minimal. Therefore, from membranes
where stress and curvature directions are aligned, and where the total
absolute stress is minimal, we can extract principal meshes with the best
static performance and with optimal visual appearance. We present then
computational tools for the design of such highly efficient gridshells. | en_US |
