Rheological and electrical properties of modified bitumen Available to Purchase

A pavement heating system was investigated as an alternative to chemical application on highway pavements. As a result, surface course asphalt mixes needed to be modified to develop improved electrical properties. The bituminous binder was outlined as that part of asphalt mixes that could be modified with filler-characterised additives. These additives included carbon black, pulverised fuel ash and iron powder. Samples were prepared and subjected to electrical tests in order to obtain the optimal additive content. The materials were subjected to rheological and electrical performance tests. Pulverised fuel ash had limited influence on the inherent electrical properties, although higher levels of substitution performed better than unmodified bitumen. The carbon black and iron powder were found to improve the capacitive and resistive properties of bitumen. Carbon black was found, however, to give the best predictability for in-service use for asphalt mixes with varying filler-to-bitumen ratios