Shani Wallis, Editor

Arup/Atkins and Mott MacDonald are significant winners in the first tranche of design contracts to be awarded by Crossrail in London.

Under a reported £16 million contract, the Arup/Atkins JV will design the TBM-excavation specifications, precast-concrete segmental lining, track systems and construction planning for the 21km of 6m diameter twin tube running tunnels under the city centre that will link Paddington in the west to Stratford in the northeast and under the Thames to Woolwich in the southeast. This extensive contract also covers coordination of all the instrumentation and ground movement monitoring needed for the central underground section of the 118km long rail integration project from Maidenhead in the west to Shenfield and Abbey Wood in the east. This includes the settlement monitoring needs at the six stations and all other intermediate access shafts and excavations on the vital underground section. The contract will coordinate assessment of the potential construction and excavation impacts on 4,410 buildings, 250 of which are historic listed buildings, and on 243 other major infrastructure assets including other rail, utility and service tunnels, and thousands of other smaller scale utilities.

The central underground section of the £16 billion Crossrail project

For its part, Mott MacDonald will design all the SCL (sprayed concrete lining) requirements on the project. Extensive SCL excavations are needed for underground station caverns at Paddington, Bond Street, Tottenham Court Road, Farringdon, Liverpool Street, and Whitechapel with SCL escalator shafts to ticket halls at either end of each station layout and concourse links to parallel SCL station platform tunnels. There are also several SCL shaft excavations needed for ventilation and intermediate access shafts on the underground alignment. These too are included in the project wide SCL design contract.

Design of the civil works at each of the underground stations, as well as design of the different portal zones on the alignment at Royal Oak; Pudding Mill Lane (with its relocation of the DLR station and rails); Victoria Dock portal in the Docklands; and the North Woolwich and Plumstead portals, are separate categories of the ‘framework’ approach adopted for design of the project. In this first tranche of design contracts awarded, Capita Symonds Ltd is awarded design of the Royal Oak Portal and Arup is awarded also the civil works of the Tottenham Court Road Station. Design of these elements excludes design of any SCL work associated with the structures. This is part of the Mott MacDonald SCL contract.

Contracts awarded to date:
• Package C150 - Royal Oak Portal - Capita Symonds Ltd
• Package C121 - Sprayed Concrete Lining - Mott MacDonald
• Package C122 - Bored Tunnels - Ove Arup & Partners International Ltd
• Package C134 - Tottenham Court Road Station - Ove Arup & Partners International Ltd

The next set of design contracts to be awarded in the coming weeks cover the civil works for Farringdon Station, the tunnel aerodynamics and ventilation package, project-wide architectural design of the stations, and award of the other portal structures and of intermediate shafts, excluding SCL elements for these structure.

Design under these contracts will advance to about 70% when construction bids will be invited and the successful contractors given the opportunity to value engineer any changes to improve constructability of the works. Under what is called ‘optimised contractor involvement’, these suggestions will be incorporated into the final design before construction starts.

In announcing the contract awards on May 29th, Graham Plant, Programme Director at Crossrail said: "The awards mark the start of the project's detailed design stage and we look forward to working closely with all the successful companies in driving forward the design as we move towards the start of main construction works in 2010."

Arup Project Director Duncan Wilkinson said the appointments build on a number of major rail projects across the world where Arup has collaborated successfully with Atkins. Arup is also lead designer on the project’s open cut Canary Wharf Station, which is being procured by project sub-partner, the Canary Wharf Group. The station contract is awarded to contractor Laing O’Rourke and groundbreaking on site last month marked the start of construction. “These events demonstrate that the project is now truly gathering momentum," said Wilkinson, “and we look forward to contributing our knowledge and skills in making the Crossrail vision a reality."