Rejuvenation Mechanism of Asphalt Mixtures Modified with Crumb Rubber

Asphalt aging is one of the main factors causing asphalt pavements deterioration. Previous studies reported on some benefits rubber mixtures through laboratory evaluation. A field observation various pavement sections crumb modified friction courses (ARFC) in Phoenix, Arizona area indicated an interesting pattern transverse/reflective cracking. These ARFC were placed several years ago existing jointed plain concrete for highway noise mitigation. Over years, shoulders had very noticeable and extensive cracking over joints; however, driving lanes showed less formation severity extent. The issue with this phenomenon that widely adopted theories stem from continuum mechanics materials layered systems cannot directly explain phenomenon. One hypothesis could be traffic loads continually manipulate time, which causes maltenes (oils resins) compounds absorbed particles to migrate out leading rejuvenation mastic mixture. To investigate validity such a hypothesis, experimental testing was undertaken condition samples without dynamic at high temperatures. This followed by creep compliance indirect tensile strength testing. results higher aged loading compared those loading. Higher attributed flexibility due maltenes. also supported fracture energy obtained conditioned