Development of Fly Ash based Geopolymer Concrete

Cement and concrete are widely used in building and construction practices throughout the world. The use of Ordinary Portland Cement (OPC) requires use of additional energy and poses environmental damage. The objective of this project is to provide a green alternative construction material to OPC by geopolymerization of industrial wastes. This study made an effort to develop a low-cost working recipe that utilizes a combination of fly ash (FA) and red mud (RM) with different additives to create a geopolymer with comparable or better performance to OPC. The effectiveness of the methodology was tested by evaluating the synthesis factors and testing the unconfined compressive strength. To reduce greenhouse gas emissions, efforts are needed to develop environmentally friendly construction materials. In geopolymer concrete, a by-product material rich in silicon and aluminum, such as (ASTM C 618 Class F) fly ash, is chemically activated by a high- alkaline solution to form a paste that binds the loose coarse and fine aggregates, and other unreacted materials in the mixture. The test results presented in this paper show the effects of various parameters on the properties of geopolymer concrete. The applications of geopolymer concrete and future research needs are also identified. Fly ash, considered to be a waste material is rich in silica and alumina and hence can be used as a source material for manufacture of Geopolymers. These binders have been reported to achieve high early strength and better durability as compared to Ordinary Portland cement based counterparts.