Properties of Glass Fiber Reinforced Concrete Using Rubber Latex as an Ingredient

This research is a study of the physical and mechanical properties of glass fiber-reinforced concrete (GRC) mixed with natural rubber latex or synthetic rubber latex. The properties studied include compressive strength, water absorption, and flexural strength of the concrete samples. The test samples for compressive strength had dimensions of 50x50x50 mm according to ASTM C190 standards. The test samples for flexural strength and water absorption were GRC thin plates prepared by spraying to a thickness of approximately 10 mm. Samples were cut into the dimension of 50x250 mm. All samples were tested under bending according to BS EN 1170-5:1998 standards. The appropriate amount of surfactant for use with natural rubber latex was determined through mixing trials to determine the compatibility of the ingredients. The main variables studied include: the amount of natural or synthetic rubber latex in the ratio of 2, 4, and 6 percent by weight of cement replacement. The samples were tested at different ages of 7, 14, 28 and 56 days after water curing. The test results found that using surfactant at 1.0 percent helped the natural rubber to mix well with the mortar without clumping. Replacing Portland cement with natural rubber latex or synthetic rubber latex tended to reduce the compressive strength of the mortar. However, the use of natural rubber latex or synthetic rubber latex would help to reduce water absorption. The lowest water absorption occurred when natural and synthetic rubber latex were used at 2 percent. In addition, the use of natural rubber latex or synthetic rubber latex in samples slightly decreased the stresses at limit of proportionality and modulus of rupture compared to the control sample. However, the toughness of the thin plate samples tended to be higher than those of the control samples when they were cured in water for a longer time.