Alternative to full depth replacement of concrete road
A449, Malvern, Worcestershire
Worcestershire County Council
Eurovia Surfacing (for Ringway Infrastructure Services)
This main Worcester Road into Malvern was suffering from severe reflective cracking caused by movement in the underlying concrete base layers. Traditionally, HRA 55/14 surfacing would be laid directly on to the concrete, but would result in the reflective cracking appearing again over time, meaning additional cost for the local authority and more disruption for local people. Other alternatives had been ruled out. Full reconstruction would have involved high costs and lengthy road closures. Using a thicker binder course and surface course would have caused problems when joining adjacent streets.
Following discussions with Worcestershire CC and their term maintenance contractor, Ringway Infrastructure Services, ULTILAYER SAMI was recommended. ULTILAYER SAMI uses the latest Polymer Modified Binder (PMB) technology and is a highly flexible stress absorbing membrane interlayer that offers proven long term crack resistance. This was then overlaid with ULTILAYER surface course which was specifically developed to combat reflective cracking and road surface deformation. Tarmac ULTILAYER combines a high performance PMB and selected aggregates, for a highly flexible, very strong and extremely durable surfacing solution.
Results and benefits
The scheme was completed over two days by Eurovia Surfacing on behalf of Ringway Infrastructure Services. Each carriageway was treated on a separate day. The existing HRA 55/14 was planed away to expose the concrete base layer. The concrete was then overlaid with 25mm ULTILAYER SAMI followed by 40mm of ULTILAYER 10mm surface course. Using ULTILAYER SAMI in conjunction with an ULTILAYER surface course, provided a lasting solution to the persistent problem of cracking. As a result, the long term condition and performance of this road, as an asset, was improved and future maintenance requirements were minimised, reducing expenditure and disruption for local people.
Solved problem of repeated cracking
Ended the costly and disruptive cycle of frequent resurfacing and failure due to cracking.
Avoided full depth reconstruction
Avoided the high cost and disruption of removing and replacing the jointed concrete road base.
Intelligent asset management
Intervening with an innovative solution improved the long term condition of the road to help reduce future maintenance costs.