Assessment of Freeze-Thaw Cycles Impact on Flexural Tensile Characteristics of Asphalt Mixture in Cold Regions
Cidan Duojie, Wei Si, Biao Ma, Yongping Hu, Xue Liu, Xintong Wang
Abstract
Low average temperature, large temperature difference, and continual freeze-thaw cycles have significant impacts on mechanical property of asphalt pavement. Bending test was applied to illustrate the mixtures’ flexural tensile properties under freeze-thaw (F-T) conditions. Experiment results showed that the flexural tensile strength and strain declined as F-T cycles increased; the deterioration of flexural tensile properties decreased sharply during initial F-T cycles but turned smooth after 15–21 F-T cycles. ANOVA showed that F-T cycles, asphalt-aggregate ratio, and gradation had obvious influence on flexural tensile characteristics. Flexural characteristics of AC-13 behaved better than the other gradations. It turned out that the mixtures’ low-temperature bending characteristics were improved when 5.5% optimum asphalt-aggregation ratio or slightly larger AC-13 gradation was applied.