HS2 LONDON TUNNELS

CCS Scaffolding Ltd are delighted to be assisting the Skanska Costain Strabag Joint Venture (SCS Railways JV) in delivering the London Tunnels section of HS2 which will see London connected to the West Midlands and beyond. Our works have so far consisted of providing access solutions for the construction of the portal at West Ruislip, the assembly of two huge Tunnel Boring Machines (TBM) as well as providing maintenance to the TBM’s following their launch, the construction of two vent shafts at South Ruislip and Northolt, multiple concrete structures at Copthall North and South including the Northolt cut & cover tunnel and the Harvil Road Rail Bridge as well as a huge conveyor system that transported the excavated aggregate across the project, reducing the number of construction vehicles on local roads. Now that the TBM’s have completed boring operations, we have now been engaged in the disassembly of these two huge machines as well as the construction of multiple cross passages that connect the twin tunnels with more portal works being undertaken at West Ruislip including the installation of structural walls, a full length porous portal, two attenuation tanks and several head houses.

Having worked closely with both Costain and Skanska previously on major infrastructure projects such as the London Power Tunnels, Crossrail, A14 Huntingdon Bypass and M1 Junction 19 Improvements and following early involvement on this project, CCS Scaffolding are proud to be providing full project management, design, TW assistance and much more whilst continuing to maintain our high standards of delivery and safety.

· General Site Access: Consistently providing site access scaffolds and edge protection in an ever changing and evolving working environment.

· Site Staircases: Designing and installing HAKI staircases to assist with safe and efficient movement of personnel on-site including several public access staircases in addition to standard HAKI stairs.

· Portal & Launch Chamber Assembly: Providing all required scaffolding and RC shutter accesses to facilitate the excavation and construction of the West Ruislip portal and TBM launch chamber including a 4m deep base slab.

· TBM Assembly: Utilising a variety of scaffolding solutions including both HAKI and traditional tube and fitting methods to support the assembly of two huge tunnel boring machines, both with eight rear gantries.

· Rail Environments: Undertaking the scaffold requirements for the Harvil Road Rail Bridge built adjacent to and over the operational Chiltern line which involved Network Rail liaison and work during engineering hours.

· WPPs & Task Briefings: Developing and maintaining detailed WPPs alongside bespoke, task specific briefings to provide SSOW for our operatives to complete high risk activities safely.

· TfL & NR Design: Providing the client with detailed design packages in collaboration with our design supplier including undertaking CAT III checks and completion Form C and acting as CRE for design.

Works on this project have been running 24/7 since the start of January 2022 and we have been present at all times, 365 days a year, assisting the client in delivery of the works as well as providing solutions for environmental protection such as designing and erecting large, complex free-standing scaffolds that were sheeted with acoustic barriers to help reduce light and noise pollution during unsocial hours. The ongoing delivery of the HS2 London Tunnels on behalf of SCS Railways has proved to be a challenging and complex undertaking that CCS Scaffolding continue to be pleased to be a part of and we look forward to the next stages of this project.

Challenges:

· Working in a densely populated urban environment with strict Section 61 restrictions.

· Managing operative fatigue during extended periods of 24/7 working.

Successes:

· TBM assembly including all scaffold design works.

· Harvil Road Overbridge, a single-span composite bridge over the Chiltern Line Railway.