Gwent County Council Office, South Wales, UK

QuadConsult Limited was commissioned by Walters Civil Engineering Contractors to provide advice on each stage of the demolition of this eight storey 1960’s concrete framed office block. The site neighbours were the A4042 trunk road and Gwent Police Headquarters.

To meet safety and public health objectives the asbestos soffit shutter under cast in situ concrete elements had to be carefully removed or stabilised before being appropriately demolished and disposed of. The building was then demolished top down whilst taking care to retain shear walls for as long as necessary to maintain stability, and to ensure that progressive collapse was not induced by overloading the lower floors.

A large transfer slab at ground over the basement car park had deep haunched concrete beams. Carefully consideration was given to proving that they were not either pre-stressed or post tensioned which could have caused debris to be jettisoned at high speed across the site or over the site boundaries.

Photographs show that one of the challenges for the contractor proved to be the demolition of large, very heavily reinforced concrete beams and columns.