Estimating compressive strength of early age frost damaged recycled aggregate concrete using nondestructive evaluation techniques

This paper aims to investigate the characteristics of concrete exposed to early frost damage and to examine the relationships between compressive strength and static and dynamic elastic moduli concerning its exposure to various frost environments. Frost initiation occurred at 1, 2, 3, 4, and 7 d, with duration of 12, 24, 36 h at - 10 celcius. Furthermore, electric arc furnace slag coarse aggregate (EFG) was used as coarse aggregate to compare its influence on the properties of natural crushed coarse aggregate (NCA). Compressive strength and static elastic modulus were measured, and a nondestructive evaluation method approach was employed to evaluate the dynamic elastic modulus. The experimental results confirmed that a significant decrease in compressive strength when the concrete is exposed to frost damage in the early stages, particularly for 24 h in low w/b. However, the early age frost damage did not significantly alter the static and dynamic elastic moduli compared to the change observed in the compressive strength. Moreover, considering the impact of early frost damage on both compressive strength and elastic modulus, a new stochastic equation was proposed. This equation can utilize the results of nondestructive evaluation to estimate the compressive strength of early frost damaged concrete.

Automated summary

This paper investigates the characteristics of concrete exposed to early frost damage and examines the relationships between compressive strength and static and dynamic elastic moduli in different frost environments. Frost initiation occurred at different durations and temperatures. The study also compares the influence of different coarse aggregates on the properties of the concrete. The experimental results show a significant decrease in compressive strength when exposed to frost damage, but no significant change in elastic moduli.