The system is also applicable in renovating historical timber floors and for this particular purpose has become important on the European market. The vast majority of research has been performed on systems where wet concrete is cast on top of timber beams with mounted connectors. To make timber-concrete composite systems further competitive in the market it is worthwhile to develop a system speeding up production and reducing on-site costs.
The shrinkage of concrete is also a pronounced problem in a wet-dry solution. Prefabricating concrete slabs with already inserted shear connectors and finally assembling timber beams moves work from the construction site to the work-shop. For a rational and dry construction process it is interesting to investigate connections, which do not implicate the curing of concrete at the building site.
The aim of the pilot project carrying at Lulea University of Technology is to evaluate a range of fasteners with both strong and rigid mechanical performance or with a reduction of strength and stiffness but high ductility already embedded into the prefabricated concrete slab. The new joining concepts consisting of shear connectors to connect glulam beam and concrete slab were investigated through shear test in autumn 2005. After shear-test evaluation, two connection types were chosen for testing in large-scale specimens. Both static and dynamic behavior was investigated in June-October 2006. Ongoing research project involves long term tests of the entire system as well.
The studies carried out on the “dry-dry” shear connectors let to provide new aspects of joining timber and concrete composite structures offering at the same time new perspective of using timber-concrete composites widely on market as industrialized product.