Two new grades of multigrade bitumen have been introduced by Mobil for use in spray sealing and asphalt applications. Binder and mix testing was undertaken to compare the performance of these new grades compared to conventional grades. Results of binder testing indicated that the multigrade bitumens improved both low and high temperature properties. Limited mix testing showed the multigrade bitumen to be very beneficial for improving pavement performance by significantly increasing the resistance to rutting and also displaying some benefits to fatigue resistance. Limited evaluations also showed that the multigrade bitumen has improved adhesive properties and this is particularly beneficial for spray sealing applications. Early field performance data supports the laboratory predictions of improved surfacing performance with the multigrade bitumens. (A)
Abstract