High Loop Slip Road - Ballieston

As nominated specialist sub-contractor of Amey for the Scottish SW trunk Road contract USL Structural Protection successfully tendered for the replacement of a bridge joint on the M8 8-8 130 M8EB to M73SB 'High Loop Slip' Road.

The M8 8-8 130 Baillieston High Loop is a multi-span overbridge crossing the M8 motorway and is principally used by M8 eastbound traffic wishing to join the M73 SB and ultimately M74 East or West. The bridge carries a 2-lane single carriageway and hard shoulder slip road. The total deck with is 13.65m. The work on the bridge comprises the replacement of the exiting expansion joint together with associated localised deck waterproofing, surfacing and concrete repairs as necessary to the bridge deck.

• Baillieston Interchange is comprised of a myriad of bridges, cuttings and embankments, set within the central lowlands of Scotland.
• There are no residential properties located within 200 metres of this site.
• The view from the carriageway is of motorway embankments
  and over bridge structures.

The contract to replace the existing joint consisted of the following:

• Site survey to ascertain and confirm existing site data
• Traffic Management; Lane and slip road closures aswell as local diversions routes.
• Installation of temporary bridging units or road plates as necessary to undertake the works.
• Removal and replacement of the existing waterproofing system within the vicinity of the bridge joint. Waterproofing of concrete decks, top abutment walls and fixed bridge joints was done by USL Structural Protection's Britdex MDP waterproofing system.
• Replacement of the existing failed expansion joint with a Euroflex M330 by RW International.
• Removal and reinstatement of verge kerbs necessary for the installation of the new joint
• Removal and reinstatement of verge kerbs above bridge joint
• Delamination survey to the exposed top surface of the bridge deck and accessible areas of deck soffit and expansion gap at the joint location
• Concrete repairs arising from the delamination survey to either side of the deck and, where appropriate, the vertical faces of the expansion gap.

Hydro demolition - The removal of the concrete inlay was completed in approximately 12 hours. A section of joint approximately 6.5 metres long was exposed via hydro demolition techniques.

Removing joint using crane lift procedures

Drilling operation

Lifting units into place

Completed joint replacement

Project Programming

The works to the bridge took place under a number of carriageway closures. They consisted of; off peak weekday/overnight closures and weekend total closures of the slip road. Temporary diversion was implemented during all full closures of the slip road.

An indicative programme was devised by Amey/Transport for Scotland and USL Structural Protection which allowed for the contract to be completed between the months of July and August to avoid peak traffic flows that usually occur when school holidays are finished. It was critical the works did not extend into September.

The installation of the new Euroflex expansion joint system and associated works was completed on time and budget to the completed satisfaction of the client.

 For more information please contact  +44 (0) 191 416 1530 or email info@uslsp.com