Heathrow Terminal 5 was designed to handle 35MPA. The passenger areas are on one level, with plant rooms and baggage handling located below. The full development includes a motorway link to M25, the creation of 2 new open rivers and the construction of more than a km square of taxi-ways and aircraft stands.
The central terminal building incorporates an extension to the Piccadilly and Heathrow express train services, in total there is 13.5km of new underground rail and roads. There is also an airside track transit system and an airside road tunnel connecting directly to Heathrow’s central terminal area.

Project Challenges

Robert Bird Group undertook a Design Review and Value Engineering Study of the Terminal structure, resulting in:

• Deletion of in-situ hydrostatic basement slabs across majority of the site in favour of innovative precast voided slab solution, eliminating hydrostatic water pressure and soil heave.
• Deletion of in-situ concrete basement walls requiring formwork and open-cut excavation, in favour of an embedded wall system requiring less excavation and minimal formwork.
• Alternate flooring system, recognised as cost advantageous, but not adopted due to lack of time for services re-coordination.

Overall RBG’s engineering ideas substantially reduced the construction programme of the basement and it’s overall carbon intensity.

Added Value

Innovative use of precast concrete slabs with in-situ joints and heave board in the basement negated the need for substantial amounts of piling and thick reinforced concrete slabs.