Joseph Chamberlain College, Birmingham

Three- and four-storey in-situ concrete post-tensioned flat slab frame

Project description

A new education facility to support expansion and relocation to a prominent site overlooking the city. The multi-functional building comprises the latest design in academic accommodation, as well as facilities for the community, including: a sports centre, performing arts facilities, a cafe and a learning resource centre. The project value was £29 million and has been awarded the RIBA 2009 Prime Minister Award.

Construction

The college is next to two busy roads so the architects have designed the college as a crescent around a quiet garden.

The new college has three to four in-situ flat slabs 325mm thick and is built on a radial grid with three rows of columns, generally spaced at 6.9m for the inner grid and 8.3m for the outer grid. The outer edge columns are blade columns of 1030 x 200mm and the other columns are circular. The concrete frame has exposed soffits and shear walls to provide thermal mass.

The C32/40 concrete used for the frame contained ground granulated blast furnace slag (ggbs) to lighten the colour of the concrete and to reduce the embodied CO2 of the frame.

The concrete benefits

The main college buildings have a largely exposed fair-faced in-situ concrete frame, providing strong thermal mass capabilities, reducing mechanical heating and air-conditioning requirements. The use of concrete and the crescent shaped design of the classrooms provides excellent acoustic performance and a robust barrier against the noise of the college’s urban setting.

Project team

Architect: Nicholas Hare Architects
Engineer: BDP
Contractor: BAM Construction