In-Situ Performance Evaluation of Glass Fiber Reinforced Polymer (GFRP) Dowel Bars

Abstract

Dowel bars have an important role in the performance and longevity of a Jointed Plain Concrete Pavement (JPCP) by providing a load transfer system at concrete joints. However, the commonly used epoxy-coated bars are susceptible to corrosion due to manufacturing and handling imperfections. To address this problem stainless steel dowels are used in corrosive environments. A more economical corrosive-resistance material for dowel bars is Glass Fiber Reinforced Polymer (GFRP), but the lack of extensive field performance data coupled with the absence of a nationally recognized test method has limited the wide application of this cost-effective alternative. To monitor and evaluate the mechanical strength of GFRP dowels under heavy truck traffic a field experimental plan was prepared and a pilot project was built on the departure lane of a Weigh-In-Motion (WIM) station on Route 37 in Sonoma County, Bay Area. To allow side-by-side comparison, the experiment included control epoxy-coated steel and GFRP dowels with different spacing. The mechanical and bonding performance of the GFRP dowels were evaluated by visual inspection, cores, and load transfer efficiency measurement using a Falling Weight Deflectometer (FWD). The four-year evaluation results suggest that GFRP dowels could be effectively used to provide a robust joint load transfer system for long-life concrete pavements. It is the goal of the Department to use the result of this experiment to add this material as an alternative to stainless steel in the concrete pavement specification.