Impact of Ethylene Glycol Addition on the Physico-Chemical and Mechanical Properties of Alkali Activated GGBFS Pastes

This paper aims at study the effect of ethylene glycol (EG) addition on the physico-chemical and mechanical properties of alkali activated slag (AAS) pastes. Ground granulated blast-furnace slag (GGBFS) was activated by 6 wt. , % sodium hydroxide (SH).0, 2.5, 5, 7.5, and 10 wt. , % of EG were added to AAS paste. The results show that, the setting times of AAS pastes elongate with the addition of EG. The drying shrinkage of AAS was reduced by ~ 7, 28, 53 and 68 % in case of AAS containing 2.5, 5, 7.5 and 10 wt. , % compared to control sample at 90 days. The chemically combined water contents increased with EG mass as, % at early ages of curing up to 7 days. The wet compressive strength decreased with the addition of EG. In contrast, the compressive strength of AAS pastes dried at 80C for 24 h increased with EG percentage up to 7.5 wt. , %. A significant reduction in compressive strength was observed in AAS containing 10 wt. , % EG at all ages of curing. Dry AAS pastes containing 0, 2.5 and 5 wt. , % showed a compressive strength regression at 90 days. The TG, DTG, FTIR and SEM proved that, the rate of polymerization of EG increases with time.