Experimental behaviour and design of composite wood floors

Fast-track construction is gradually becoming a reality in composite timber-concrete construction thanks to a new generation of quick-fix shear connectors. To achieve the enhanced shear strength, ductility and stiffness, two similar and yet highly engineers geometric configurations were produced, for hard and softwoods respectively. These were then subjected to standard push-out tests to determine the load-slip laws as a function of the wood type. Both laws were essentially elasto-plastic, however, the hard to softwood stiffness ratio was 6, the maximum load ratio was 1.5 and the ductility ratio was unity. On the basis of these observations, a series of composite floors using both wood types were designed and tested according to EUROCODE 5 with measurements of the end-slip, deflection and strain distribution. While the rigidity enhancement capability of the new sheer connectors. was clearly visible in terms of the. load-carrying of the composite assembly. However, we realise that the softwood deflected twice as much as hard woods for the same connector distribution. The results of a comparative study of the different tests were presented and finally a methodology is proposed for the optimum design of composite wood-concrete floors.