We delivered a range of work on the CTRL project. Including the C230 station box at Stratford, which is a 1.1km, 62m wide, 25m deep station box linking twin tunnels into Stratford and the C430 Ashford project, 17km of track, cut and cover tunnels through the centre of Ashford, as well as twin tunnelling on the C220 and C240 contracts.
The works included:
- Installation and operation of 100m deep well dewatering scheme
- Driving twin 8.15m diameter running tunnels lined with fibre reinforced precast concrete bolted tapered lining rings
- Woodgrange Road ventilation and intervention shaft to a depth of 36m deep with Barrington Road shaft to a depth of 45m
- Excavation of eight cross passages between the running tunnels using traditional timbering methods and cast-iron lining
- Design, construction and operation of the on-site precast concrete manufacturing facility to provide the tunnel linings for C240 and C230 contracts
- Over 1,000 properties and 2km of surface railways were all inspected in advance of the works and precautionary measures taken to mitigate any effects of ground movement
- Enabling works were undertaken to allow the tunnels to pass within 4m of the Central line tunnels, which remained live throughout the works
- All spoil was moved using a conveyor to its stockpile and reused
- TBMs achieved excellent progress peaking at 930m in 28 days
We delivered the contracts ahead of schedule and on budget. We maintained full transparency of our works with all stakeholders and minimised the impact on the environment and local communities by reducing the delivery traffic on and off site.
On the Ashford project, we kept the trains running on the existing network whilst installing the new line through the centre of Ashford, with links to the existing International Station.