The paper describes the demolition of Bernard House, an office building in the centre of Manchester, which was a necessary enabling operation for the redevelopment of the Piccadilly Plaza.
The Piccadilly Plaza is a 1960s development of two multi-storey office buildings alongside a multi-storey hotel, all sitting on a plinth of car parking, shops and basement storage. At 10 storeys high, Bernard House was the smaller of the two office buildings, its floors were supported by a central core and above the third floor by perimeter reinforced concrete window mullions. The third floor was a post-tensioned prestressed concrete slab which supported, at its perimeter, the structural concrete mullions and therefore the upper floors. Demolition of the slab is this paper’s main subject. The main technical difficulty was linked to the slab’s post tensioning. However, the demolition process was generally made harder by the city centre location and the adjacent busy bus/metro station.
G. Sellors, CEng, FIStructE
Principal Engineer, Babtie Group Ltd Sale, Cheshire