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HOCHTIEF rebuilt four bridges and raised parapets on twelve bridges spanning the Great Western Mainline to create clearance for overhead line electrification between Heathrow Airport and Maidenhead as part of the wider Crossrail scheme. The demolition and replacement works were all successfully completed within two possessions at Christmas 2012 and Easter 2013.

Key features:

  • Reconstruction of 4 bridges: 1 road bridge and 3 footbridges
  • Parapet modifications to 12 rail overbridges
  • Working in possessions
  • Temporary footbridges
  • Utilities diversions
  • Lighting
  • Drainage

To ensure that we could complete the bridge reconstructions within the planned possessions, we standardised the design across all three footbridges. Each bridge was rebuilt using 32m single span weathering steel braced girders with precast composite concrete decks, allowing fast installation, maximising efficiency across multiple sites, and providing long term cost savings by minimising future maintenance requirements.

We retained existing elements of the bridges where possible, installing precast concrete portals and parapets on the existing piers of the road bridge to save time, maximise safety and reduce waste. We also delivered the piling for the footbridge foundations next to the live railway on time, despite difficult ground conditions. 

By carefully studying the works and implementing measures to minimise the risk of overrun we were able to reduce possession times, while collaborative planning with the wider Crossrail team enabled us to complete all possession works on or ahead of programme.

We delivered the scheme on time and to budget and achieved both a Considerate Constructors Performance Beyond Compliance award and 3 Network Rail Star awards.