Predicting Mixing and Compaction Temperatures of Polymer Modified Bitumen

Despite many advantages of using polymer additives in bitumen, there are several challenges bordering on standards and specifications with regards to their utilization. One of these challenges is related with specifying the required heating or mixing and compaction temperatures of the polymer modified bitumen. The standard method (ASTM D 2493) aims to determine mixing and compaction temperatures of the base or unmodified bitumen. Nevertheless, the application of this method in the case of polymer modified bitumen led to very high temperatures which may not be appropriate for PMB. In this paper, some alternative methods named as the high shear rate and steady shear flow method suggested in the literature have been examined and tested for 50/70 and 160/220 penetration grade bitumen samples involving an elastomeric type of additive. A suggested method has also been proposed to overcome the complexities in the implementation of the alternative methods.