Influence of freeze–thaw damage gradient on stress–strain relationship of stressed concrete.

Freeze–thaw damage gradients lead to non-uniform degradation of concrete mechanical properties at different depths. A study was conducted on the stress–strain relationship of stressed concrete with focus on the freeze–thaw damage gradient. The effects of relative freeze–thaw depths, number of freeze–thaw cycles (FTCs) and stress ratios on the stress–strain curves of concrete were analyzed. The test results demonstrated that freeze–thaw damage was more severe in the surface layers of concrete than in the deeper layers. The relative peak stress and strain of concrete degraded bilinearly with increasing depth. The stress–strain relationship of stressed concrete under FTC was established, and it was found to agree with the experimental results. [ABSTRACT FROM AUTHOR]