THOUSANDS OF tons of fresh asphalt planings are piling up in a field beside the A10 Wadesmill Bypass in Hertfordshire. They come from a virtually brand new, untrafficked dual carriageway that was undermined by sulphate attack on the lime stabilised capping layer.
Nearby contractor Fitzpatrick is in the middle of a trial use of the planings as a replacement capping material. Tests are being carried out on a range of gradings and compaction options. Although recycling of newly laid asphalt is 'not that unusual', according to the Highways Agency, it is usually confined to small works.
According to site personnel the best compaction to date has been achieved by a standard vibrating roller, which outperformed the sheepsfoot roller also trialled.
More than 6,000t of asphalt is already scheduled to be removed from the bypass, and the total could go much higher. If the trials are not successful the project's green image will be tarnished, and local residents will have to tolerate thousands more lorry movements than anticipated.