Airport pavement concrete often suffers from freeze–thawing damage in high latitude and cold areas. In addition, the use of aircraft deicer makes the airport pavement concrete suffer from salt-freezing damage. To improve the durability of airport pavement concrete, modified polyester synthetic fiber (FC), cellulose fiber (CF), and basalt fiber (BF) reinforced concrete were prepared in this paper. The mechanical strength, pore structure, and frost resistance (freeze–thawing and salt freezing) of fiber-reinforced concrete were investigated. The effects of the combined action of fiber (fiber type and content) and surface treatment methods (spraying silane and impregnating silane) on the frost resistance of concrete were investigated. The results show that the flexural strength of concrete is positively correlated with the elastic modulus of fiber, but has little effect on the compressive strength. Fiber can reduce mass loss and dynamic modulus loss of concrete subjected to frost damage. FC more effectively improved the frost resistance of concrete than CF. After 30 cycles of salt freezing, the spalling amount of concrete sprayed or soaked with silane was decreased by 65.5% and 55.5%, respectively. Adding fiber and impregnating silane reduced the spalled concrete by up to 70.5%. Spraying silane treatment is better than impregnating silane treatment in enhancing the frost resistance of concrete because a better silane condensation reaction is achieved with spraying silane.

Effective improvement of the frost resistance of concrete in cold regions is critical for the durability of airport pavement concrete in plateau. This paper intends to contribute to a better knowledge of the effects of combined air-entraining superplasticizer and surface treatments on the resistance against freezing-thawing and salt freezing. First, an optimum mixing by considering w/c, cement content, sand ratio, and air-entraining superplasticizer was obtained by comparing compressive and flexural strength, microstructure, pore distribution, and resistance to freezing-thawing of different mixes. From the results, a concrete mix with air-entraining superplasticizer, w/c = 0.4, cement amount at 330 kg/m3, and sand ratio = 0.3 was selected for airport pavement. Then, this mix was subjected to salt freezing with different surface treatments (smoothing, brushing, spraying with silane, and impregnating with silane), and the spalled mass loss in salt freeze cycles was reported. The results show that combined use air-entraining superplasticizer and surface treatments can provide an obvious improvement on the resistance to salt freezing. Compared to silane impregnation, surface treatment by silane spraying performed much better in early time.