Effects and mechanisms of the coupling action of freeze–thaw and abrasion on desert sand concrete

Abstract In cold regions, concrete channels are subjected to the combined effects of freeze–thaw cycles (FTC) and abrasion, leading to severe deterioration of the channel structures. However, the performance of desert sand concrete (DSC) under common environmental conditions such as freeze–thaw and abrasion remains unclear. In this study, desert sand (DS) was used to partially replace river sand (RS) to prepare. The performance variations of river sand concrete (RSC) and DSC under FTC, abrasion, and freeze–thaw–abrasion coupling action were investigated. Microstructural analysis of the concrete was conducted using scanning electron microscopy (SEM) to explore the damage mechanisms of DSC under the freeze–thaw–abrasion coupling action. The results indicate that incorporation of DS enhances the FTC resistance and abrasion resistance of the concrete. Under the sole action of abrasion, the abrasion resistance of DSC was 59.7% higher than that of RSC. Under the same number of FTC, the compressive strength of DSC consistently remained higher than that of RSC. Under the freeze–thaw–abrasion coupling action, the abrasion resistance of RSC and DSC decreased by 64.5% and 63.39%, respectively. Microstructural analysis revealed that the coupled damage from freeze–thaw and abrasion is far from a simple superposition of individual effects, exhibiting a significant synergistic interaction: FTC causes structural loosening of the concrete, exacerbating abrasion damage, while surface damage from abrasion accelerates water ingress, thereby intensifying freeze–thaw damage. This study provides theoretical insights for the practical application of DSC in engineering projects in desert and cold regions.