An assessment on the durability performance of fly ash-clay based geopolymer mortar containing clay enhanced with lime and GGBS

Abstract

The increased demand for cement as a construction material led to its humongous production and hence the emission of carbon dioxide. The geopolymer binder is an alternate binder which make use of aluminosilicate surplus industrial and agricultural waste and hence completely devoid of cement. The current study primarily aims at investigating the durability performance of low calcium fly ash based geopolymer mortar containing clay blends. Two types of clay treated with lime, ground granulated blast furnace slag (GGBS) and lime-GGBS combination was used in the study. The optimization tool used was the central composite design in response surface methodology by which a set of trial mixes were obtained. The design trial that exhibited maximum compressive strength and lower water absorption was taken as the optimum mix. The durability characteristics of the optimum mix in terms of water absorption, sorptivity, abrasion resistance, acid attack resistance and sulfate attack resistance were analyzed. Combination of lime-GGBS incorporated clay-based specimens exhibited better durability characteristics. The test results were discussed with microstructural characterization techniques such as X-ray Diffraction analysis (XRD) and Fourier Transform Infrared Spectroscopy (FTIR).