DURABILITY CHARACTERISTICS OF POLYMER-MODIFIED GLASS-FIBER REINFORCED-CONCRETE

The main thrust of this research was to assess the effectiveness of polymer emulsions in enhancing the durability characteristics of glass fiber reinforced concrete (GFRC) materials. Alkali-resistant (AR) glass fibers at a 6 percent weight fraction and an acrylic polymer emulsion at different dosage rates were used in this investigation. Accelerated aging of the material was achieved through immersion in hot water Interior storage in air was also used to provide control test data. Polymer addition led to significant improvements in the flexural strength and toughness characteristics of GFRC materials. Aging in air in interior conditions had no significant effects on the flexural performance of GFRC materials with or without polymer emulsion. Accelerated aging in hot water led to major losses in flexural strength and toughness of GFRC. Although polymer-modified GFRC materials had higher flexural strength and toughness at all periods of hot water immersion, polymer addition could not prevent the loss in flexural performance of GFRC with accelerated aging. Scanning electron microscope observations suggested that the loss in flexural performance with accelerated aging was caused by the penetration of cement hydration products in between the glass filaments. This process was not altered by the presence of polymer emulsion.