Laboratory Characterization and Evaluation of Durability Performance of New Polyester and Vinylester E-glass GFRP Dowels for Jointed Concrete Pavement

This paper presents an experimental study that investigated the physical, mechanical, and durability characteristics of newly developed vinylester- and polyester-based glass-fiber-reinforced polymer (GFRP) dowels through a collaboration research project with the Ministry of Transportation of Québec (MTQ). Durability performance was first evaluated with a preliminary set of conditionings in different solutions. The long-term performance was then assessed under harsh alkaline exposure simulating the concrete environment. The alkaline exposure was achieved by immersing the dowels in an alkaline solution at elevated temperatures to accelerate the effects. Thereafter, the properties were assessed and compared with the unconditioned reference values. The test parameters were (1) type of resin (vinylester and polyester), (2) diameter of GFRP dowels (25.4–44.8 mm), (3) temperature (23, 50, and 60°C), and (4) conditioning time (30, 60, and 180 days). The test results revealed that the vinylester-based GFRP dowels were stable and did not show significant changes in their properties after being subjected to an alkaline solution for 180 days at 60°C. The long-term predictions revealed that the transverse shear-strength retention of vinylester- and polyester-based GFRP dowels would decrease by 10 and 26%, respectively, after 100 years at 10°C. Based on the findings of this research, a new material specification for GFRP dowels was formulated by the MTQ in order to ensure product performance and longevity.