Prefabricated, pre-stressed composite timber floor modules for high performance applications

The research presented herein is focused on the development of prefabricated timber-to-timber composite floor modules to be assembled by using laminated veneer lumber (LVL) made of beech wood. The assembly procedure for pre-stressing and cambering timber composite floors, that was developed at the University of Trento and validated over the last few years, was adopted in order to maximize material efficiency and exploiting the remarkable strength properties of hardwood. Several experimental tests (including push-out and pull-out test configurations) were performed to characterize the mechanical behaviour of the connection system. Finite element models and analytical formulations were calibrated on the experimental results and used for designing the floor modules. Two scenarios were considered: 10 m long diaphragms for office areas and schools and 6 m long diaphragms for residential buildings. Finally, the floor modules defined in the design phase were tested up to failure by performing full-scale six-point bending tests. The test outcomes appeared as promising especially when the floor modules are compared to more "traditional solutions" (e.g. concrete floors, timber-to-concrete and timber-to-timber composite structures), in terms of structural thickness, material saving and mechanical performance.