Investigating the relationship between chemical composition and mechanical properties of asphalt binders using atomic force microscopy (AFM)

•New asphalts with different SARA content are designed, and the composition-structure-mechanics relationship is analyzed.•Bee structures are composed of asphaltene and resin.•Micro-mechanical properties of asphalt binders are affected by two fractions together rather than one single fraction.•The effect of SARA on rheological properties at both macro- and micro-scales of asphalt binder show the same trend.