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Applying foamed warm-mix asphalt in pavement has attracted great attention, but its effects on asphalt mastic are not clear. This research investigated and compared the performance characterization of asphalt mastic prepared by foamed and unfoamed binders. The functional group information, thermal behavior, and rheological characteristics were explored using a series of experiments. Results show that both foamed and unfoamed asphalt mastics have similar function groups, which indicates that foaming process does not change the infrared absorption structure of asphalt mastic. Besides, asphalt foaming seems not affect the thermal stability of mastic, although some foaming water is still present. The high- and low-temperature performances of asphalt mastic were slight weaken by foaming water, but the effect is not significant based on the analysis of variance. The asphalt–aggregate interaction of asphalt mastic is significantly improved by the foaming behavior. This study concluded that foamed asphalt mastic could achieve the similar performances with unfoamed asphalt mastic. [ABSTRACT FROM AUTHOR]

• The performances of foamed warm mix binders and mixtures containing reclaimed asphalt pavements were evaluated. • Foamed asphalt and mixture have a better low- temperature performances and fatigue life than those of unfoamed ones at the same RAP content, but have a worse high-temperature performances and water stability. • Asphalt foaming relieves the effects of RAP on asphalt and mixture performance. • Foamed asphalt mixture contains RAP could meet the standard requirements when RAP does not exceed 30%. Concerns exist regarding whether residual foaming water will be unfavourable for the performance of asphalt and mixtures when foamed warm mix asphalt (FWMA) binders are combined with reclaimed asphalt pavement (RAP). A series of experimental methods was utilised to evaluate the performance of FWMA–RAP binders and mixtures. It was found that the FWMA–RAP binder performance was consistent with that of the mixtures. Foamed asphalts and mixtures exhibited better low-temperature performance and had longer fatigue lives than their unfoamed counterparts did at the same RAP content, but exhibited worse high-temperature performance and lower water stability. The RAP content had a significant influence on the asphalt and mixture performances and appeared to aggravate the effect of asphalt foaming. Foamed asphalt mixtures containing RAP were able to satisfy the standard requirements when the RAP content did not exceed 30%. [ABSTRACT FROM AUTHOR]