M48 Severn Bridge Main Cable Inspection

In October 2015, ABUK staff, under the banner of American Bridge International (ABI) started work on the M48 Severn Bridge in the United Kingdom. This  GBP 2.5M contract involved providing access and project management to facilitate the client’s inspection of nine main cable panels on the 1960’s suspension bridge crossing the Severn Estuary between England and Wales. The work at each panel involved the removal of Cableguard and wire wrap, cleaning of lead paste residue, wedging open of the wires, wire sampling and repairs, re-compaction and replacing wire wrapping, Cableguard and re-enabling of the dehumidification system.​

Low Level Access Platforms​

The contract involved the design and execution of low (LLP) and high level access platforms (HLP) to facilitate the main cable inspection. The LLP was a tube and fitting scaffold had to satisfy various constraints. It also had to withstand the specified wind loading. ABI worked with our sub-contract scaffolder to ensure the scaffold roof was designed to withstand the highest levels of wind speed permissible in the existing design codes. The design was further revised at the request of Highways England and Severn River Crossings PLC to try and avoid having to remove the scaffold roof during moderate winds and risk delaying the works.​

High Level Access Platforms​

The HLP was a bespoke design and fabricated gantry system. The HLP allowed for the inspection of 2 high level main cable panels at different locations on the bridge. The design had to allow for wind loading at maximum levels, permanently sheeted roof and retractable side curtains for the containment of lead dust and for the handling of materials and equipment to and from the man riding access cradle.​

Traffic Management​

ABI worked to innovate and expedite the works where it was safe to manage traffic. Manual activities such as loading and unloading materials from the low and high level platforms was replaced with much quicker truck mounted crane handling. Training was provided for all operatives so that the learning curve duration was dramatically reduced.​

These measures expedited the overall project by 2 months, creating a significant reduction in traffic management and benefitting the local community who use the bridge daily.

Project Details

  • Location: UK
  • Structure Type: Complex Structures
  • Client: Severn River Crossings PLC
  • Delivery Model: Design-Build
  • Project Value: GBP 2.5M
  • Status: Active