Description
The use of crumb rubber as a binder modifier could contribute to solving waste tire disposal problem and to improving the qualities of road pavements, such as the reduction of viscosity-temperature susceptibility, rutting and cracking etc. However, the key point to industrialization of asphalt rubber in plant scale is the hot storage stability, which includes two main aspects, the differences between upper and lower layers after being stored for a period of time, and the attenuation of properties along with time. The effects of processing and recipe factors on the hot storage stability were investigated in this study. Reclaimed crumb rubber was chosen as the modifier for base asphalt Baoli70#. It was found that the stability of the asphalt rubber was highly dependent on properties of crumb rubber, and the chemical compositions of the binder. In this paper, 30 wt % reclaimed rubber modified asphalt with proper hot storage stability was obtained under common polymer modified asphalt conditions. The small amount of SBS (styrene-butadiene-styrene tri-block copolymer) vulcanized by sulfur obviously improved the hot storage stability of reclaimed rubber modified asphalt (RRMA), especially under common processing conditions (185℃, shearing for 45 min).