Reinforced and post-tensioned structural glass shells: Concept, morphogenesis and analysis

Laccone F.

Structural glass  Shell  Fail Safe Design  Damage Avoidance Design  Post-breakage behaviour  Post-tensioning  Hybridism  Hybrid structure  Triangular glass panel  Architectural Geometry  Computational Design  Membrane forces  Funicular  Reverse Engineering  Finite Element Model. 

The relationship between architecture and structure is a key point in the conceptual phase of a building or one of its components. Glass structures can be considered optimal from the material usage viewpoint because they simultaneously offer transparency, an idea always pursued by architects, and good structural performances. Transparent and free-form glass shells are fascinating objects from both the aesthetic and structural engineering point of view, but are practically difficult to realize, apart from limited favourable cases, and have a low safety level. This work explores a new structural concept for triangulated glass shells, in which the glass panels are both reinforced and post-tensioned. Hence, the net formed by the reinforcements constitutes a redundancy barrier to avoid global collapse in case of glass cracking. In order to ensure an adequate safety level, glass should be prevented from carrying tensile stresses. To this aim, a novel algorithm is developed for the automatic design of the piecewise geometry of the shell and the derivation of the optimal cables distribution with respective preloads. Global nonlinear analyses have been performed to prove the feasibility of the concept and to highlight the advantages that these structures offer with respect to the grid shells competitors. At the local level, the main components of these systems are investigated: the node is tested experimentally and its behaviour is successively described numerically, and the triangular laminated panels are explored with parametric nonlinear models. The thesis is written as a monograph. Some papers prepared during the study are included as part of the work.