Effect of additives on carbon dioxide uptake and compressive strength of dry-cast concrete. Issue 6 (18th March 2021)

• Record Type: Journal Article
• Authors: Matalkah, Faris; Jaradat, Yaser; Soroushian, Parviz; Weerasiri, Rankothge
• Is Part Of: Magazine of concrete research. Volume 73:Issue 6(2021)
• Page Start: 288
• Page End: 301
• Publication Date: 2021-03-18
• Subjects: admixtures -- carbonation -- compressive strength; Concrete -- Periodicals; Concrete construction -- Periodicals; Concrete -- Testing -- Periodicals; 624.1834
• DOI: 10.1680/jmacr.19.00183
• Languages: English
• ISSNs: 0024-9831

Abstract

Abstract : The main thrust of the work reported herein is to study the effect of chemical additives to make beneficial use of carbon dioxide in enhancing the compressive strength of dry-cast concrete. The additives used in this investigation were calcium and magnesium oxides and silicates, nickel oxide, sodium hydroxide, sodium bicarbonate and strontium chloride. The experimental results showed that both the carbonation reactions and the compressive strength of dry-cast concrete mixtures were improved when using chemical additives. Experimental investigations for optimisation were also undertaken with selected additives to further increase the carbon dioxide uptake and improve the compressive strength. The best results were obtained when using calcium silicate in combination with calcium oxide. The early-age compressive strength of specimens made from the optimised mixture increased from 9·82 MPa to 13·32 MPa, and the specimens' carbon dioxide uptake increased from 8·76% to 10·62% of cement weight.