Review of Thaumasite Sulfate Attack on Cement Mortar and Concrete

Abstract

Durability is one of the most important considerations regarding the design of new concrete structures in aggressive environments. Thaumasite sulfate attack (TSA) is one durability consideration. This paper reviews the features of TSA, factors affecting TSA, thaumasite formation mechanisms, and prevention measures. Finally, some needs for future studies are also suggested. TSA can completely destroy the cementitious binding ability of concrete by transforming it into a mush. Many factors affect thaumasite formation and TSA. The four primary factors affecting TSA on portland cement-based materials are low temperatures (below 15°C) and the presence of sulfates, carbonates, and moisture. Apparently, the dissolution–precipitation mechanism can be used to explain most phenomena during TSA. A procedure for field studies is also proposed. Both material compositions and surrounding environments should be considered for the prevention of TSA in concrete structures.