ULTILAYER
Durable resurfacing for residential roads
Addison Avenue, Enfield, London
Client
London Borough of Enfield
Contractor
Marlborough Highways
Location type
Addison Avenue, Enfield, London
Completion
August 2019
The challenge
Regular trafficking and on street parking had caused surface cracking and deformation on this residential avenue in North London. Core sample reports showed that the existing hot rolled asphalt surface had been laid on top of an unbound sub base. The potential for instability in the base would increase the risk of future cracking and presented a challenge for highways engineers when resurfacing the road. A deeper plane out and full depth reconstruction would mean extended road closures, a rise in material and disposal costs and additional vehicle movements. This would be disruptive for residents and also carried the risk of unearthing tar contaminated material incurring significant disposal or processing costs.
Our solution
After discussions with Tarmac’s Technical Product Support Manager, ULTILAYER 6mm SMA, Tarmac’s high performance polymer modified asphalt was identified as a solution. ULTILAYER combines outstanding flexibility and strength to deliver longterm durability, even on the most difficult sites where conventional materials have failed. The advanced polymer modified binder would provide enhanced flexibility and durability needed to cope with vehicle manoeuvring, static loading from parked cars and any underlying movement in the sub base. ULTILAYER can be laid in a single layer, to replace the surface and binder course. This enables faster resurfacing but also accommodates the restrictions in pavement depth that are a frequent challenge when resurfacing residential streets.
Results and benefits
As planned the existing surface was planed out to 30mm and around 250 tonnes of ULTILAYER 6mm SMA was supplied and laid. The innovative approach chosen by Enfield for this resurfacing scheme, allowed work to be completed quickly in just three days with minimal loss of access or disruption to local residents. Significant cost savings were achieved by avoiding full depth reconstruction. Fewer outbound and inbound vehicle journeys were also a welcome advantage given the sites proximity to the busy North Circular Road. No complaints were received by the council for the duration of the resurfacing work and the new 6mm surface also provided a smooth even finish and a quieter surface for householders living on the Avenue.