Strength degradation mechanism and modeling of freeze‐thaw foam concrete

Abstract In order to investigate the strength degradation mechanism of foam concrete in freeze‐thaw environment, some samples were used for freezing‐thawing cycles test and mechanical test. Based on the experimental results, the mechanism of strength degradation was analyzed, and a strength degradation model was established. The results show that the mass loss rate and peak strength degradation rate of foam concrete follow a power function with the number of freezing‐thawing cycles increase, while the longitudinal wave velocity degradation rate follows a quadratic function. Under the action of freeze‐thaw cycles, microcracks in the foam concrete skeleton propagate deeper, increasing pore connectivity and reducing its bearing capacity. Using the least squares method, a strength degradation model for freeze‐thaw foam concrete was developed, with the error between theoretical and experimental data controlled within 3.5%. This model effectively describes the peak strength deterioration process of freeze‐thaw foam concrete.