Durability Behaviour of Geopolymer Concrete with Metakaolin and GGBS

Abstract

This study consists of preparation of Geopolymer concrete mix with Ground Granulated Blast furnace Slag (GGBS) which is followed by the usage of Metakaolin in replacement of GGBS with 5% variation from 0 to 25%. From previous researches on geopolymer concrete with GGBS, an optimized mix is selected and tested for durability behaviour. A 12 Molarity sodium hydroxide solution along with sodium silicate in the ratio of 1:2.5 is used as activator in this study. La Hypercrete S25 which belongs to the category of carboxylic is used as admixture for escalating the workability. Water absorption, Acid resistance, and Rapid Chloride Penetration (RCPT) are the durability tests performed on the specimens. The prepared specimens are water cured at room temperature for the required days in accordance with the codal guidelines and tested for durability. For water absorption test, concrete cylinders of 50mm dia and 100mm height are prepared. 100 mm size cube specimens prepared for acid resistance test. The specimens for RCPT include preparation of discs of 100 mm dia and 50 mm height. In all the test specimens, GGBS is replaced by Metakaolin. It is believed from the test results that geopolymer concrete with Metakaolin and GGBS performs well in durability aspects.