Innovative Timber-Concrete Composite Structures with Prefabricated FRC Slabs

This paper concerns the development of innovative composite floor systems, comprising timber beams and prefabricated concrete slabs. For the development of this new system, two properties were regarded as vital, as follows: (1) good stiffness, and (2) a high degree of prefabrication. Shear connection systems installed using completely dry processes were used. Innovative and very efficient materials, such as fiber-reinforced concrete (FRC) and modified wood, were used for the manufacture of the specimens. The research reported in this paper was conducted in two phases, as follows: (1) the mechanical properties of different shear connectors were investigated (Phase A), and (2) on the basis of these experiment's results a second investigation was carried out in order to study the behavior of full-scale timber-concrete composite slabs (Phase B). During Phase A four different configurations, with a total of eight specimens, were laboratory tested in shear. During Phase B two full-scale floor elements, each with a different shear connection system, were laboratory tested in bending. The two shear connector systems used in the investigation were (1) shear anchor-keys of furfurylated wood, and (2) inclined steel tubes. Both of the proposed connection systems performed more than satisfactorily, showing a very high degree of composite action even at load levels close to the failure load. Moreover, it appeared that the assembling of the prefabricated fiber-reinforced concrete slab with the underlying beams occurred in an extremely easy manner. (C) 2014 American Society of Civil Engineers.