A Study on the Performance and Storage Stability of Crumb Rubber-Modified Asphalts

Crumb rubber-modified asphalt (CRMA) with good storage stability was prepared using activated crumb rubber. The activation of crumb rubber was carried out by blending crumb rubber with polymeric compatibilizer in extruder to improve interaction between crumb rubber and asphalt. The softening point difference (SPD) and photomicrographs were used to reveal the storage stability of CRMA. The long-term storage stability test results indicate that the softening point difference of CRMA was below 2.5 degrees C. The rheological characteristics of the binders were studied with a dynamic shear rheometer (DSR) and a bending beam rheometer (BBR). The results showed that the CRMA binders are possessed of the better resistance to permanent deformation at high temperature and cracking at low temperature than those SBS-modified and straight-run asphalts.