SubscribePier 3 Segregation Information from WSP Group.
Scope Of Services Provided
The aim of this project was to replace the existing track transit system between Pier 3 satellite and the South Terminal, and provide a segregated route for departing and arriving passengers. It consisted of a total of 440m of elevated walkway on two levels with a vertical circulation core at either end.
Main Challenges
The main challenge was to build a new Pier in a live airport environment, interfacing with all the operations that go on almost 24 hours a day. The bridges crossed airside roads, were immediately adjacent aircraft stands, the track transit system, and connected into the South Terminal, the South Terminal coaching station and the Pier 3 Satellite. 
All these operations remained live during construction and disruption had to be minimised.
The new pier also had to be co-ordinated with existing facilities such as the Terminal and the adjacent Pier 2. Due to these constraints, and in order to meet BAA's requirements to minimise time on-site, it was decided to maximise prefabrication. The corridor product came to site with its cladding, wall finishes, ceiling-mounted plant equipment and distribution systems, and lighting.
The walkways, made up of these corridor modules, were supported on three 'bow string' structures spanning 56m between vertical circulation towers. The towers contained the building services plant and associated vertical distribution space.
Work was also carried out on protection of the building from damage resulting from traffic collision. The project required that passengers would not be inconvenienced during construction, but there was a period when the transit system had to be switched off in order to complete the passenger connections to the bridge.
As a result, advice was given on coaching routing and arrangements for access for this short period.
Another challenge was to understand influence of jet engine blast on the walkways and corridor modules when the aircraft were being pushed back from their stands. To understand this aspect, our environmental engineers undertook computer modelling using a CFD programme to ascertain the expected forces from the engines, so that they could be taken into account in the structural and envelope design.
In order to provide space to construct the bridge and buildings, advice was given on the modification of the layout of aircraft stands at pier 3, so that the largest stand could be retained, and regular airline users of the pier would not be inconvenienced.
The displacement of the blast screen in order to permit construction of the bridge section temporarily shortened the cul-de-sac/taxiway, which therefore required the narrowing of one stand, and departing aircraft to be pushed back to the west side of the pier. The blast screen was finally relocated at the end of the project to a new position clear of the new bridge.
Lessons Learnt
Lessons learnt from previous projects on the maintenance of lighting over stairs and escalators were incorporated into this project, to the satisfaction of the Client's maintenance engineers.
Value: £51m
Project Timespan: 2003 - 2005
Services provided: Mechanical & Electrical Services, IT Network and Comms, Structural Engineering, Traffic Engineering, Environmental Studies.
