FRP Dowels for Concrete Pavements

A Paper for the World Wise Conference 1999 Winnipeg, Manitoba © November 15, 1999 Introduction Joints are used in concrete pavements in order to control cracking due to thermal and environmental conditions. Dowels span joints to transfer load from one slab to an adjacent slab and to provide vertical and horizontal alignment. Currently, smooth epoxy coated steel dowels are placed across transverse joints to transfer load and to allow for longitudinal thermal expansion and contraction. Corrosion of steel dowels due to the application of de-icing salts causes severe deterioration of concrete highway pavements due to the expansion of steel during the corrosion process. This expansion can create large stresses, sufficient to cause cracking and spalling of the concrete. This also causes a reduction of the load that the joint can transfer. In an attempt to reduce the effect of de-icing salts on dowels, epoxy coated steel dowels are used. Small defects during handling inevitably occur in the epoxy coat. Thus, corrosion remains a problem with the epoxy coated steel dowels and therefore, a better solution must be found. Fiber reinforced polymer (FRP) dowels could provide an alternative solution to steel dowels due to their corrosion-free characteristics. FRP material is known for its high ultimate tensile strength in the direction of the fibers, however, it has a relatively low strength perpendicular to the fibers. An experimental study was conducted at the University of Manitoba to provide data on the behaviour and performance of FRP dowels for concrete highway pavement joints.