Mitigation of waste rubber tire and waste wood ash by the production of rubberized low calcium waste wood ash based geopolymer concrete and influence of waste rubber fibre in setting properties and mechanical behavior

摘要

World-class trend set was focusing on finding an alternative for cement which is a major pollutant to the environment by releasing greenhouse gas emission. Meanwhile, disposal of waste by generating a suitable method for its effective utilization is a major role of researchers in global. Geopolymer is one of the most suitable alternatives for the utilization of all industrial wastes with aluminosilicate source material in which has a disadvantage of requirement of high alkaline solution and exposed temperature curing. In this study, alternative for cement in the view of low calcium based geopolymer was introduced to reduce the aforementioned problem in GPC. Meanwhile, GPC has a problem on less brittle, less energy absorption and impact resistance. Rubber tire is a huge available waste material which is most harmful to the environment if it burnt. Waste rubber tire has a property of high elasticity and it has an abundant way to use in the concrete. In order to counteract the aforementioned problems, waste rubber as a fiber was added at a variation of 0.5, 1, 1.5 and 2% of volume fractions. The addition of fibre up to 1 percent improved the setting properties and mechanical behaviors in all ages of curing. At the age of 90 days, the compressive strength, split tensile strength, flexural strength and modulus of elasticity of low calcium geopolymer mix was increased by 4.36%, 6.25%, 3.64% and 10.62% respectively. Further, addition of waste rubber fibre beyond 1 percent results in decreasing of all strength parameters.