M4 Viaduct Repairs

Main Steel Sub-Contractor on highly time-critical and high profile repairs on the M4 Boston Manor Viaduct (May to July 2012).

…a unique repair solution involving the manufacturing of bespoke specialist steel plates and their installation over the crack.”
Highways Agency press release July 13th 2012

Shortlisted as a finalist for the Integration and Collaborative Working category in the 2013 Construction Excellence Awards.

“In addition to the pure resilience demonstrated by the entire team, key to the success was the tremendous respect the project team had for each other and their support for the goal of the project. The stabilisation of Boston Manor Viaduct shows what can be achieved when teams work together coherently, safeguarding the structure and minimising the risk of costly and disruptive closures occurring in the future.”
Osborne Project Report

Ongoing investigations had revealed unexpectedly severe cracks in the steel structure. These had resulted from fatigue due to the age of the viaduct (opened 1965), stress, and some fabrication flaws.

The urgency of the repairs could not have been greater, the viaduct being part of the Olympic Route Network, carrying coaches to and from Heathrow airport and the Olympic Park. Closure of the M4 threatened to remove one of the key arteries for Olympic traffic.

BS Steels was asked to carry out repairs including a mixture of grinding and manufacture of special steel plates to be bolted above and below cracks to the web. Technical and logistical challenges from the highly complex process for the plates were numerous:

  • In addition to the bolt plates, filler plates were required on both sides, between the structure and the new bolt plates; these had to be milled to match as exactly as possible the unique profile and undulations of the existing structure. This had to be done for around 30 separate locations.
  • The existing structure had to be drilled to highly exacting tolerances. To keep up with demand, drill bits had to be sourced constantly from all over Europe!
  • Each plate had multiple tension control bolts, needing systematic tightening; this could only be done during overnight closures, to eliminate traffic loads.
  • Continuous re-programming of schedule on a daily basis: need for exceptional communication and collaboration between all parties.

The emergency repairs were completed just in time for the Olympics. The Highways Agency received the following message from the Permanent Secretary on behalf of the Prime Minister:

“I want to pass on my personal thanks to all those who worked so hard to repair the M4 bridge and get it open again in time for the Olympics. You showed real determination to get the job done in time, working through the night to do so. I was delighted to get the news very early this morning.”

You can also download a full project report (PDF) by main contractor Osborne.

The lessons learned through the innovative repair solutions have since been put to use on other locations, notably the M25 Gade Valley Viaduct

M25 Viaduct Strengthening and Repairs

Students from West Herts College visiting BS Steels site at Gade Valley ViaductMulti-year project strengthening the welds on the underside of the viaduct spans on the M25 Gade Valley Viaduct. BS Steels’s longest continuous project, with a dedicated team likely to be on site for several years. Read more...

Steel for the Hospitality Sector

Ham yard Hotel, Soho, London; steelwork by BS SteelsBS Steels has an impressive record in the hospitality sector. Working with many leading hotel, restaurant and pub companies, as well as individual operators, we are proud to have been part of some amazing transformations. Read more...

Highway Works and Repairs

BS Steels team working on expansion joint replacement, M25 Gade Valley Viaduct May 2018ISO 9001:2015; National Highway Sector Scheme No 20 qualifies BS Steels to supply, manufacture and install any highways or railway asset involving steel. Repairs are a particular focus. Read more...

Old Thorns Manor Hotel

aerial view of old thorns apartment block under constructionThe largest and most complex example of BS Steels’s work in the hospitality and leisure sector. It is also a prime example of BS Steels’s principal contractor services, delivering seamless project management on behalf of the client. Read more...

Distribution Centre Jersey

installing new steel canopy, Ferryspeed warehouse JerseyWarehouse Conversion and extension to enable delivery, loading and storage in optimum temperature-controlled conditions. Read more...

Railway Parapet Marcon Place London

Detail of railway parapet by BS Steels, Hackney, London E8Design, manufacture and installation of new railway bridge parapet at Marcon Place, London, within a very challenging timescale. Overall project ‘Highly Commended’ in 2013 Network Rail Partnership Awards. Read more...

Railings, Ramps, and Grilles

Steel is a very suitable and versatile material for railings, ramps, staircases, decorative and security grilles. Browse a selection of BS Steels projects across many sectors. Read more...

Mixed Retail/Residential Refurbishment

Stainless steel staircase reflected in mirror131 Shoreditch High St, London E1. Structural steel manufactured and installed for new floor layouts. Architectural staircases and features in mild and stainless steel. Read more...

London Office Block Refurbishment

Steelwork at St Paul's House, London, by BS SteelsComplex office block refurbishment, with basement completely revamped, ground floor lowered to existing pavement level. Included new steel staircases, creation of service voids, new steel sixth floor and roof. Read more...

London Gateway Reception Building

assembling London Gateway admin building, Thames estuary in backgroundDesign, fabrication and installation of steelwork for reception building of the UK’s newest deep-sea container port and Europe’s largest logistics park. Read more...

Community Church, Springhead Park, Kent

steel framework, front view, north kent community church, springhead parkNorth Kent Community Church. Manufacture and erection of steel superstructure for North Kent Community Church, Ebbsfleet. Erected to schedule through some of the worst winter weather for many years. Read more...

Sports Complex within Listed Building

steel framework for mezzanine floor, hms temeraire, portsmouthGrade II Listed Building Refurbishment. Steel mezzanine, stairs, balustrades, and glazed steel entrance canopy designed, manufactured and installed by BS Steels. Read more...

Central Mosque, Portsmouth

Steels installed by BS Steels, ready for new floor aboveInstallation of new mezzanine floor, significantly adding capacity and enhancing utility of building. Read more...