STUDY ON THE CONSISTENCY AND SETTING CHARACTERISTICS OF FLYASH BASED GEOPOLYMER

Production of Portland cement is consuming significant amount of natural resources and emitting considerable fraction of the totally generated carbon dioxide to the atmosphere. Research made on making concrete without cement has come to a viable level of developing geopolymer concrete. Considerable research has been carried out to study the compressive strength of geopolymer concrete with different mixing proportion and test variables but, there is not much data available on the short term engineering properties like consistency and setting characteristics even though it establishes the time available for placing, compaction and transport of Geopolymer. For a wide range of applications and acceptance of GPC in concrete industry, much more studies on the binding property of geopolymers are needed apart from other properties of geopolymer mortar and geopolymer concrete. The dosages of activating solution, the curing temperature and curing period are yet to be optimized for the requirements. A fundamental study on the setting characteristics of low calcium flyash based geopolymer with molar concentration of Sodium hydroxide 8-14M and liquid ratios of sodium silicate to sodium hydroxide as 1.5-3.0 and curing temperature of 65oC is made and the informative results are presented.