Pre-stressed post-tensioned building demolition

Connell Brothers were appoionted to carry out the demolition of bomb-damaged structures in Manchester City Centre after the IRA attack in 1996. The demolition included a nine-storey building comprising of a two-storey retail Marks & Spencer store, with Michael House, a six storey office block, located on the podium above the Plant Room.

Michael House was supported by five pre-stressed post-tensioned beams, which in turn were supported on columns passing through the two storeys of the store to sub-basement level. Particular attention to detail was required with the specialist techniques involved in the destressing/dismantling of the post-tensioned beams. The Project also called for the demolition of retail units along St. Mary's Way and an office block (Macintosh House) to the northern elevation of the busy Shambles Square Piazza.

Due to the location of the site and building construction, Connell Brothers appointed Dr. John Roberts of Allott & Lomax Consulting Engineers, to deal with aspects of the structural tower, and the University of Manchester Institute of Science and Technology to carry out monitoring for the de-stressing of post tensioned beams.

The Project has been acclaimed by leading engineers in the industry as a 'world first'