| Composite bridge decks have been shown to display compressive membrane action to a varying degree depending on their level of lateral restraint. The compressive membrane action tends to increase the strength and reduce the deflections of bridge deck slabs. Since the adaption of an empirical design method that accounts for the development of compressive membrane action, considerable reduction in the cost of bridges has resulted. It has also been shown by research that further reduction in the deck slab thickness with enhancement in serviceability is possible by transversely prestressing the deck slab. It is believed that, by replacing steel prestressing tendons with fibre reinforced plastic tendons, the durability of the bridge deck slab could be prolonged, because these materials have better corrosion resistance than steel to the saline environments bridge decks are subjected to. This thesis reports an experimental investigation undertaken to study the punching behaviour of composite bridge decks transversely prestressed with Carbon Fibre Reinforced Plastics (CFRP) tendons.;A 1/4.04-scale model of a short-to-medium span, two-span, three-bay, simply supported composite bridge deck was constructed and tested under a static concentrated wheel loading. The main variable in the study was the material of the prestressing tendons. A total of six (three pairs) panels were tested and the results compared to those of a similar steel-prestressed bridge deck tested by Weishi He (1992).;It was found in the study that it is feasible to use CFRP tendons to transversely prestress composite bridge decks and, hence, enhance compressive membrane action. Further, the CFRP-prestressed bridge deck showed a better overall structural performance than the steel-prestressed deck, and there was no cause for concern with the lack of plasticity of the CFRP tendons. |
