Influence of cement type on resistance to attack from two carboxylic acids

TY - JOUR

T1 - Influence of cement type on resistance to attack from two carboxylic acids

AU - Dyer, Thomas

N1 - The author would like to thank Mr Andrew Forsyth for assistance with the experimental work reported in this paper. The author also wishes to acknowledge the use of the EPSRC-funded National Chemical Database Service hosted by the Royal Society of Chemistry.

PY - 2017/10

Y1 - 2017/10

N2 - In a number of circumstances, concrete may be required to possess resistance to organic acids. These are frequently carboxylic acids. This paper examines the effect of two such acids – acetic and butyric – on hardened cement paste specimens made from three cement types – Portland cement (PC), a combination of PC and fly ash (PC/FA), and a calcium sulfoaluminate cement (CSA). Specimens were exposed to solutions of the acids and deterioration characterized in terms of mass loss and pH measurements, micro-CT scanning, and chemical and mineralogical analysis. Additionally geochemical modelling was used to further examine the mechanisms involved during acid attack. The CSA cement was most resistant to attack, with the PC paste displaying the least resistance. This resistance has been partly attributed to the higher acid neutralization capacity of CSA cement. However, this paper demonstrates that the enhanced performance is most probably the result of a denser microstructure.

AB - In a number of circumstances, concrete may be required to possess resistance to organic acids. These are frequently carboxylic acids. This paper examines the effect of two such acids – acetic and butyric – on hardened cement paste specimens made from three cement types – Portland cement (PC), a combination of PC and fly ash (PC/FA), and a calcium sulfoaluminate cement (CSA). Specimens were exposed to solutions of the acids and deterioration characterized in terms of mass loss and pH measurements, micro-CT scanning, and chemical and mineralogical analysis. Additionally geochemical modelling was used to further examine the mechanisms involved during acid attack. The CSA cement was most resistant to attack, with the PC paste displaying the least resistance. This resistance has been partly attributed to the higher acid neutralization capacity of CSA cement. However, this paper demonstrates that the enhanced performance is most probably the result of a denser microstructure.

KW - Acid attack

KW - Portland cement

KW - Fly ash

KW - Calcium sulfoaluminate cement

KW - Acetic

KW - Butyric

U2 - 10.1016/j.cemconcomp.2017.07.004

DO - 10.1016/j.cemconcomp.2017.07.004

M3 - Article

SN - 0958-9465

VL - 83

SP - 20

EP - 35

JO - Cement and Concrete Composites

JF - Cement and Concrete Composites

ER -