Effects of Coarse Aggregate Content and Salt Solution Concentration on Freeze-Thaw Damage in Concrete

Freeze-thaw (FT) damage is one of the main factors affecting the durability of concrete structures. This paper focused on the effects of the coarse aggregate volume fraction (CAVF) on FT damage to concrete in different salt solution concentrations (SSCs). The dynamic elastic modulus (DEM) and cumulative scaling quantity (CSQ) were obtained by rapid FT tests to investigate the CAVF's influence at different SSCs. Both the dynamic elastic modulus and cumulative scaling quantity became worse with the increasing FT cycles. The dynamic elastic modulus increased with an increasing coarse aggregate volume fraction, but the cumulative scaling quantity decreased significantly. Meanwhile, the salt solution concentration had little effects on the DEM and CSQ. Furthermore, an empirical prediction model for evaluating the relative dynamic elastic modulus (RDEM) considering the CAVF was established via regression analysis and validated by experiments. A prediction model for assessing the relative cumulative scaling quantity taking into account the effects of the loss rates of the RDEM and CAVF was developed, and it correlated well with the experimental results.

Automated summary

Freeze-thaw damage is a significant factor affecting the durability of concrete structures. This study found that the coarse aggregate volume fraction has a notable influence on freeze-thaw damage, while the salt solution concentration has minimal effects. The dynamic elastic modulus increases with an increasing coarse aggregate volume fraction, while the cumulative scaling quantity decreases significantly.