Asphalt Mixes for Roundabouts
Roundabouts have become the most utilised form of traffic management in the urban environment. They are also subject to high levels of stress due to turning and braking movements.
There are a number of options for the paving of roundabouts however, the Australian Asphalt Paving Association (AAPA) recommends the following:
- Asphalt should be dense grade, preferred 14AC (75 Blow Marshall).
- Class 320 bitumen should be used as the binder, possibly modified for heavy traffic.
- Corrector layer depth should be appropriate to the stone size (5x).
- Traffic should not be allowed on the asphalt until sufficiently cool (not exceeding 40°C)
- The limits in brackets are not AAPA comments but are recognised as industry standards.
- Roads 2000 supports the recommendations from AAPA.
- Less stiff asphalts may be considered in low traffic local roundabouts.
Roads 2000 can provide advice to clients on the mix designs where required.
- IPWEA/AAPA Technical Specification, Tender Form and Schedule for Supply and Laying of Hot Asphalt Road Surfacing (Rev 3, April 2002)
- AAPA Fundamentals of Bituminous Surfacing (2010)
- AAPA Advisory Note 3 A Guide to Asphalt Mixes for Roundabouts (undated)