Case Study: Structural Steel Fabrication

Blackfriars Bridge and Station Redevelopment

Recommendations for future projects to improve the structural steel fabrication and installation processes

Structural steel fabrication and installation on the Programme

Bourne Group had a long relationship with the as they were appointed the structural steel contractor at both Farringdon station, and Bridge station.

Structural steelwork at Blackfriars included:

- The temporary passenger staircases and access routes. - The main station façade.

The Blackfriars Challenge

Bourne Group was involved in the Blackfriars Bridge and Station Redevelopment project providing structural steelwork for both the main station in the north and the new south bank station either side of the River Thames.

During the early construction phase, Bourne Group supplied the temporary steel walkways and staircases to assist with the diverted passenger flows. It was challenging right from the beginning because the work site was not only near the railway but also on a bridge, over a road and a river!

The main station comprised of several functional spaces. These included a retail area, an escalator building, a common entrance area with a curved, fully-glazed feature façade which was supported by steel bow-string trusses.

The south bank station was more architectural. For example, the ‘flying staircases’ do not have support columns and were purely attached to the old, existing structure. It isn’t easy to attach a major new item to a pre- Victorian structure as there are often unexpected problems. The south bank station also has a pavilion building, a west and east entrance and a glazed, steel, lift shaft structure.

The temporary work structures installed by Bourne Group were on the project’s critical path and were essential as a part of the Blackfriars reconstruction programme.

One lesson from Blackfriars – Better alignment of steelwork and cladding contracts

The project involved large areas of fully glazed façade and so the cladding contractor had a higher work package value than Bourne Group. For this reason, the façade contract led the steelwork contract. This caused problems for the structural steel team as their work would always be installed first. The steel supplier did not have information at the beginning that they needed, and this managerial structure went against the natural flow of the project. This caused many problems and delays and so an important lesson learnt for Bourne Group was that they should never subcontract to cladding contractor in future.

Author

Case Study produced by Howard Cox, Bourne Group, February 2019.

Further information

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