Experimental research on mechanical behaviors of GFRP bridge decks under alkaline solution

Glass fiber-reinforced plastic composites are particularly attractive as bridge deck systems due to their high strength, low density, and excellent corrosion resistance, which are of importance to the bridge industry. According to ACI 440.3R–04, the tests consisting of 100 glass fiber-reinforced plastic bridge deck samples were conducted to evaluate the mechanical behaviors of glass fiber-reinforced plastic bridge decks (including tensile property and flexural property) in terms of temperature of the alkaline solution and time period. The parameters of temperature included 40℃ and 60℃, and the investigated corrosion time included 3.65 days, 18 days, 36.5 days and 92 days, respectively. The micro-formation of the glass fiber-reinforced plastic bridge deck samples surface were surveyed under scanning electron microscopy, which indicated that corrosion pits on the surface of glass fiber-reinforced plastic bridge decks became obvious and the interface between fibers and resins was severely damaged with the aging time and temperature increased. After being exposed to alkaline solution for 92 days at 40℃ and 60℃, the tensile strength of glass fiber-reinforced plastic bridge decks decreased by 35.43% and 40.58%, respectively, while the flexural strength decreased by 21.36% and 42.10%, respectively. In addition, the degradation model of tensile strength and flexural strength of glass fiber-reinforced plastic bridge deck under alkaline solution were proposed based on Arrhenius equation.