SAG2_3

HOCHTIEF demolished and replaced four road-over-rail bridges in central London as part of TfL’s Structures and Tunnels Investment Portfolio (STIP). Ardleigh Green Bridge carries the four lanes of the A127 Southend arterial road over the East Anglia Railway.

Key features:

  • Road-over-rail bridge deck demolition and construction
  • Service bridge
  • Complex utilities diversions
  • Traffic Management
  • Phased reconstruction

As the bridge crosses rail lines, we optimised our construction method to reduce our reliance on possessions and minimise disruption to the operational railway.

We demolished the eastern side of the bridge during a 74-hour rail possession, protecting railway assets by lowering the OLE and installing a track protection crash mat before demolishing half of the bridge and trimming the abutments. We successfully completed the works in line with the QSRA programme within the possession and we handed the track back one and a half hours ahead of schedule.

We adapted our bridge design to maximise offsite prefabrication, reducing time on site and enabling us to lift in structural elements during short rail possessions. We built the eastern deck offline then launched it across the railway using a Self-Propelled Modular Transporter (SPMT). This increased quality and safety and ensured that we could complete the eastern bridge installation within the allocated possession, preventing delays. Once the eastern section was complete, we demolished and replaced the western side. The final works to demolish the remaining support piers to the old structure were completed over Christmas 2020.

We won a Considerate Constructors Performance Beyond Compliance award and were shortlisted for a British Construction Industry Award in the Temporary Works Initiative of the Year: Civil Engineering category. All four lanes of traffic reopened in 2019.