In order to analyze the water damage to different warm mix asphalt binders from the micro scale, five kinds of asphalt binders, 70#A base asphalt, sasobit warm mix asphalt, energy champion 120°C (EC120) warm mix asphalt, aspha-min warm mix asphalt, sulfur-extended asphalt modifier (SEAM) warm mix asphalt, under different conditions (dry/wet, original/aging) are prepared for laboratory tests. The atomic force microscope (AFM) is used to observe the surface properties and measure the adhesion force between the asphalt and the mineral aggregate. ...