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.

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.

Reduction of hazardous incinerated bio-medical waste ash and its environmental strain by utilizing in green concrete.

Incinerated Bio-Medical Waste Ash (IBWA) is toxic waste material with broad potential (cancer, genetic risk, premature death, permanent disease) to inflict severe health damage for the atmosphere and humans. This waste is disposed of as landfill, which contaminates the underground water and environment. The effective way of disposal of IBWA is by utilizing it as a building material, which can reduce the hazardous toxic materials. The use of Geopolymer Concrete (GPC) combined with IBWA as a substitute for Ground Granulated Blast Furnace Slag (GGBS) has been researched for its ability to create a new type of Green Concrete. The physical and chemical properties were observed for the raw materials. IBWA was used at 0, 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50% replacement by weight for GGBS. Mixing proportions were 1:2.21:3.48 respectively for GGBS, Manufacturing Sand (M-sand), and coarse aggregate. Fresh properties and mechanical properties were examined for all specimens. The findings show an increase in the setting time and flow of concrete and a decrease in density with improved utilization of IBWA. On the other hand, IBWA replacement for GGBS enhanced the mechanical properties. These results revealed that IBWA could be partially replaced as source material for Geopolymer Concrete. This research may contribute to the reduction of dangerous IBWA as a building material.