Enhancement of triisopropanolamine on the compressive strength development of cement paste incorporated with high content of wasted clay brick powder and its working mechanism

Using ground clay brick powder (CBP) replacing cement to prepare blended binding system is an effective solution to reduce the accumulation of wasted clay bricks. However, the increased incorporation ratio of CBP causes a drawback of decreased mechanical property. The present research is aiming at using triisopropanolamine (TIPA) to alleviate the excessive loss of compressive strength of cement paste incorporated with highcontent of CBP. Furthermore, the hydration behavior of cement-CBP-TIPA system is investigated in detail. The study indicated that the addition of TIPA improved cement hydration and pozzolanic reaction of CBP, thereby the compressive strength was improved at different ages. More specifically, the presence of TIPA accelerated the conversion of AFt to AFm as well as the dissolution of aluminum and iron ions from CBP, thus more calcium aluminosilicate hydrate was formed. In addition, the economic and environmental effect was also assessed. It was proved that 47% of energy consumption and 47% of carbon footprint can be saved by developing the cementCBP-TIPA binding system.