Uploaded November 2022 | Updated September 2026, 3 weeks ago
The A55 at Dobshill is one of North Wales' busiest interchanges, at the gateway to the holiday resorts and mountains of North Wales. Tarmac were employed by the Welsh government to undertake surfacing works on the busy section, which required repair of the existing concrete carriageway, and placement of a 'sami' layer, to reduce the risk of reflective cracking and improve the pavements projected life span prior to surface course. The site and road users had previously suffered from poor ride quality, and the client additionally required to explore what technologies and working methods could be utilised to improve the ride for the travelling public.
As the scheme required a full closure for surfacing operations, the full width 4metre drum was deployed, to reduce time taken for the initial milling operations. All further milling was undertaken with multi-plex averaging beam to reduce bumps and provide a smoother foundation for the surfacing.
The surfacing operations were carried out with two pavers in echelon, to remove the centre joint, and create a homogenous surface that would resist future failure at this known weak point in any pavement. To improve the ride quality material transfer vehicles 'feeders' were used to eliminate the need to stop whilst paving and allow for a constant paving speed. The pavers were additionally fitted with a combination of averaging beams and joint matchers to remove any deviations left following the multi-plex milling.
This technology resulted in an exceptionally smooth pavement, that when tested, only recorded 8 defects under 4mm, well within the allowable 362 over its 2.7 kilometre length.
#walesroad
#tarmacworks
#roadtech
The A55 at Dobshill is one of North Wales' busiest interchanges, at the gateway to the holiday resorts and mountains of North Wales. Tarmac were employed by the Welsh government to undertake surfacing works on the busy section, which required repair of the existing concrete carriageway, and placement of a 'sami' layer, to reduce the risk of reflective cracking and improve the pavements projected life span prior to surface course. The site and road users had previously suffered from poor ride quality, and the client additionally required to explore what technologies and working methods could be utilised to improve the ride for the travelling public.
As the scheme required a full closure for surfacing operations, the full width 4metre drum was deployed, to reduce time taken for the initial milling operations. All further milling was undertaken with multi-plex averaging beam to reduce bumps and provide a smoother foundation for the surfacing.
The surfacing operations were carried out with two pavers in echelon, to remove the centre joint, and create a homogenous surface that would resist future failure at this known weak point in any pavement. To improve the ride quality material transfer vehicles 'feeders' were used to eliminate the need to stop whilst paving and allow for a constant paving speed. The pavers were additionally fitted with a combination of averaging beams and joint matchers to remove any deviations left following the multi-plex milling.
This technology resulted in an exceptionally smooth pavement, that when tested, only recorded 8 defects under 4mm, well within the allowable 362 over its 2.7 kilometre length.
#walesroad
#tarmacworks
#roadtech
