Lower costs and simpler specifications for building roads could be the result of groundbreaking new Austroads-funded ARRB research.
The research, featured in a newly-released Austroads technical report, proposes merging four grades of polymer modified binders (PMBs) into two in the Australian PMB specification.
The proposal comes after extensive testing showed similar performance for comparable polymer modified binder grades (S20E/A20E and S25E/A15E) in asphalt and sprayed seals.
“If the number of PMB grades can be reduced it will simplify jurisdiction specifications,” says ARRB’s Principal Technology Leader Dr Robert Urquhart, who wrote the report. “It could also reduce production costs as binder suppliers will need less tanks to store different PMB products.”
The PMBs studied consisted of bitumen blended with styrene butadiene styrene (SBS) polymer. This is the most commonly used polymer to modify bitumen in Australia. PMBs are used in high stress road environments as they produce roads which are more resistant to cracking and rutting than conventional bitumen.
ARRB’s Dr Robert Urquhart will present an Austroads webinar overviewing the work conducted in Austroads project TT2037 on 8 August. This will give an overview of the PMB research and describe the development of a new laboratory test which can rank the low temperature cracking performance of PMBs in sprayed seals.