Mechanical Engineering, bridge bearings, structural engineering Specialists In Structural Movement Control
Mechanical Engineers Specialising In Structural Movement Control
Supplied: 48 K series
Special Pot Bearings
A370 Long Ashton Bypass, Yanley Lane Bearing Replacement
Ekspan Ltd. was employed in 2001 to conduct a inspection of the existing Glacier bearings installed in the early 1970s. The recommendation following this survey was that the bearings could be refurbished provided that the load and articulation criteria had remained constant with the original design. Following an analysis of the bridge deck, the client opted for the full replacement of the bearings due to the variation in articulation. The bearing schedule resulting from the current analysis dictated that pot bearings must be used due to the rotational requirements. This was potentially problematical due to the limited available space and the access for installing upper fixings.
Job Brief
Background Information
Project Team
Client: North Somerset Council
Client Consulting Engineer:Arup
Main Contractor Consulting Engineers:Cass Hayward & Partners
Main Contractor: Makers Civil Engineering
Start Date: December 2003
Completion Date: April 2004 (supply)
Bearings
Ekspan Ltd. supplied 48 no. special pot bearings to the project. All bearings had the requirement of only being able to utilise 2 top fixing bolts into the outer side of the beams. This was due to the restricted height available and the internal sides of the beams being inaccessible due to concrete infill. The bearings were designed such that the horizontal loads of the fixed and guided bearings were shared between the 2 top fixing bolts and an epoxy. The epoxy shear strength being approved based on previous testing results on the epoxy supplied by Ekspan Ltd. The 8 no. guided and free sliding bearings also had to be inverted due to the upper surface plan area restrictions. These bearings were supplied with rubber skirts to protect the stainless steel sliding surface.
All of the bearings supplied were manufactured in the UK by Ekspan Ltd. and incorporated the following quality features:
1. TIG Welded mirror polished stainless steel mating sliding surfaces.
2. Dimpled and greased PTFE sliding surfaces.
3. 2 brass ring sets and recessed elastomer pads.
These features enhance bearing life and reduce the risk of premature replacement being required. These quality features are included as standard on all Ekspan Ltd. pot bearings.
Ekspan's Solution