Blenheim Centre Post-tensioned System
Blenheim Centre in Hounslow was built in 2006. Phase one of the construction was a 55,550sqm structure that would provide a residential area with 487 flats, a retail development which includes a supermarket, management centre and medical centre in the mezzanine level and a 415 space car park in a single level below ground beneath the retail development on the main building.
Freyssinet was responsible for the design, supply and installation of the post-tensioned system used in the slabs of the two buildings forming phase one of the project.
The main building is a structure comprising a mixture of steel and RC columns with post-tensioned slabs at all levels. Special design consideration was given to the ground floor slab to isolate it temporarily from the columns and perimeter retaining/support walls, thus solving restraint problems until the slab had finished all movements at which point the slab was “locked” to the columns by grout infill.
Next to the main building is an eight level block of residential apartments in an L-shape with 200thk concrete slabs employing a bonded post-tensioning system, the slab spanning between blade columns.
The slabstress 4S15 bonded system was the main choice for the general construction as this is well suited to the regular square shaped pattern of the majority of the floors. The exception is the residential levels on the main crescent shaped building whose curved shape lends itself more effectively and economically to the 1F15 unbonded system.