Engineering Design Consultants

Humber Bridge A Frames

In 2009 Eadon Consulting were invited by Arup to assist them with the design of replacement bearings for A-Frame regeneration work on the Humber Suspension Bridge. Components of the bridge, the longest in the world when opened back in 1981, were in need of replacement after becoming worn.

Eadon produced the design of replacement arrangements to allow for longitudinal movement of the bridge and also accommodate vertical and transverse loads. A new solution was developed which saw the functions of the A-Frame split into 2 separate mechanisms.  The original functions of the A frames were split into two separate solutions. Vertical load is now transferred into the support towers by a pair of pendles located at the ends of the main span. The transverse loads generated by wind are resisted by a wind shoe. Longitudinal movement is not resisted but is accommodated by both systems. Bearings in the wind shoe are pre-loaded onto a running surface hydraulic system to ensure the bearings never come out of contact.

Due to the restricted space beneath the carriageway at the support towers much of the work done as part of this project had to be carried out on scaffolding platforms which created an expanded, uncluttered working area underneath the bridge deck. This was one of several obstacles engineers had to bear in mind when working on the design of the 5 tonne A-Frames. The replacement solution has been designed to ensure the equipment can be inspected and maintained for many decades into the future. 

Eadon Consulting also supported Arup with the analysis of the temporary works interfaces for the existing bridge. The maintenance is now fully competed. 

For more information regarding our structure design services or to discuss your bridging requirements, please telephone 0114 399 0400 or email us

Key Facts
  • Location:
    Yorkshire, England
  • Client:
    Arup