Carbonation and permeation behaviour of geopolymer concrete containing copper slag and coal ashes

Abstract

The current study primarily evaluates the carbonation and permeation resistance of coal bottom ash (CBA) and copper slag (CS) based geopolymer concrete (GPC). The strength parameters along with non-destructive tests were also performed for reference. CS and CBA were used as a 10%, 30% and 50% replacement of natural fine aggregates (NFA). Fly Ash (FA) was used as a binder and all seven mixes were subjected to oven curing at 65 °C for 24 h. The molarity of NaOH was kept constant (12 M) along with Sodium Silicate/Sodium Hydroxide ratio of 2. With inclusion of CS the carbonation depth, initial and capillary absorption has been decreased by 30%, 23% and 19% respectively with respect to control mix. The above-mentioned values have been increased by 28%, 27% and 58% in CBA based GPC. GPC mix containing 30% replacement of CS as sand has been considered to be appropriate for carbonation and permeation aspects.