6 / 2021-04-29 21:30:12

The impact of extended heat exposure on rapid sulphoaluminate cement concrete up to 120˚C

R-SAC concrete; thermal damage; R-SAC cement paste; thermal resistance; stress-strain

This study examined the stability of rapid sulphoaluminate cement concrete (R-SACC) when exposed to heat for extended periods of time. The physicochemical processes present in R-SACC as a function of temperature were determined through various tests. The general behavior of rapid sulphoaluminate cement (R-SAC) at a range of temperatures is summarized. Between 50˚ and 120°C, the rapid sulphoaluminate cement (R-SAC) paste first expanded and then shrank, and the shrinkage rate of R-SAC was much greater than that of R-SACC. The results show that observing color change could be a simple way to identify deterioration of R-SACC. The matrix formation of ettringite was broken and the mass of the hydrated product decreased with heat exposure; the major mineral composition of the paste consisted of CaSO4, CaCO₃ and β-C₂S; and the interface between aggregate and paste in the R-SACC become loosely structured with cracks.