Self-Compacting geopolymer Concrete: A review

Abstract

Concrete is the material which is most utilised after water and requires surplus quantity of Portland cement. Portland cement is produced with the consumption of huge amount of energy, and also leads to enormous emission of carbon dioxide (CO2) and other harmful greenhouse gases. Hence, it becomes important to find a substitute to the existing one. Geopolymer concrete is a unique kind of concrete that do not use Portland cement in its preparation and greatly reduces CO2 emissions and is also resilient to most of the durability issues. Geopolymer concrete is an environmental friendly concrete as it relies on minor treated natural materials or industrial wastes like (Fly ash, GGBFS and silica fumes etc) which are having high alumina and silica content, to significantly reduce the carbon footprints. The issue of disposal of such industrial wastes can also be resolved to great extent as their disposal causes land pollution. Alkaline solution, made by mixing sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) or potassium silicate (K2SiO3) and potassium hydroxide (KOH), is used to activate these cementitious binders. Self-compacting geopolymer concrete (SCGC) was developed to overcome failure due to lack of adequate compaction. SCGC is an improved form of concrete that compacts under its own weight without the need for extra compaction. This paper critically reviews the effect of various parameters like binding materials, molarity, superplasticizer, fibres and curing temperature on the workability and mechanical properties of SCGC along with the identified gaps and future scope. The existing literature supports the use of SCGC in place of conventional concrete not only due to lesser environmental impacts associated but also due to better waste utilisation and resource conservation in the SCGC.