BADMA TAYE, DR. A. GLADWIN ALEX
This paper is a state of the art review of the use of geo-polymer cement for road applications. Geo-polymer cement is an alternative to Portland cement and is either naturally occurring rock-based or industrial byproduct based. Geo-polymer cement has been used around at least for the last 30 years. In recent year it has become an attractive potential alternative to Portland cement. The main reason for this renewed interest is the issue relating to the release of carbon dioxide in to the atmosphere during the manufacture of Portland cement. It is estimated that 1 ton of Portland cement produces approximately 1 ton of CO2 during its manufacture. The use of geo-polymer cement can reduce this amount by as much as 90%. It is claimed that this will have a huge potential in reducing national targets in CO2 emissions of many countries around the world. This state of the art review critically evaluates existing literature relating to these claims and focuses on the potential use of geo-polymer concrete for road applications. In addition to environmental benefits, the existing literature suggests that geo-polymer cement concrete has the potential to provide better mechanical properties than Portland cement concrete. Attractive properties include quicker compressive strength development, higher compressive and flexural strength, minimal shrinkage and residence to chemical-attack and freeze-thaw cycles. The review will consider the different types of geo-polymer cement, its properties and whether it can be used in road applications.