Oxford Circus Tunnel Cooling

London

Project scope

Following experience gained during Step Free Access options study at Oxford Circus Station, London Underground commissioned Faber Maunsell to carry out a RIBA C Stage study to examine how cooling can be provided to the platforms for the Central, Bakerloo and Victoria Lines.

An options study was undertaken to consider differing methods of providing cooling. These included underplatform void air extraction using fans, use of water from boreholes to supply platform fancoils and fresh air supply using fans. An option comparison was undertaken for combinations of the potential cooling elements.

Ventilation design was key to determining the optimum cooling solution at the station. The ventilation design was integrated with tunnelling considerations for available space in the station.

Following preferred option selection, multi-disciplinary design was undertaken to RIBA C stage. The main element of the design for the Central Line was usage of an existing fan to exhaust hot platform air from the modified underplatform void.

For the Victoria and Bakerloo Line northbound direction, a new fresh air supply fan was proposed to deliver air from louvers on Argyll Street to both running tunnel which would be moved towards the platforms by the trains. Additional cooling was provided by platform overhead fancoils which were supplied by cool borehole water extracted from 150m below Argyll Street. The output warm water is return to the ground by pipes in the Victoria Line Northbound tunnel to a fanshaft leading to surface where reinjection boreholes are located.

For the Victoria and Bakerloo Southbound platforms a ventilation headhouse structure was proposed at Cavendish with louvers taking in air supplied through an existing access tunnel towards the running tunnels. Platform overhead fancoils were used in the same way as for the Northbound platforms

Tunnelling works to make all necessary connections was designed. The electrical and water layouts were designed. Pumping equipment layouts and borehole supply water parameters were assessed for water routings. Architectural impacts of the works at street level and in station public areas were studied.

Contract value

£270000

Key features

• Appraisal of cooling options at station
• Co-ordination with LU Tunnel Cooling Project Team
• Ventilation design
• Tunnel design
• Electrical design
• Water supply design
• Architectural design
• Multi-disciplinary design to RIBA C stage

Appointment

• Transportation
• Rail Engineering

Client

London Underground