In 2017, Hughes & Salvidge were awarded the role of Principal Contractor for the demolition works on Building 2/012 – Light Fabrication Hall, at HM Naval Docks, Portsmouth.
The building consisted of a 2/3 storey office at the southern elevation and a steel-framed workshop. The office part of the structure was concrete-framed with brick and masonry. The main scope of works consisted of fencing to secure the working area and the protection of live services, before the soft-strip and demolition of the building to ground floor slab level. The building was located centrally within the Naval Base. It was therefore imperative for the site to be kept secure and fenced off at all times, and for dust, noise and vibration from our works to be minimised with our methods as much as possible.
Hughes and Salvidge conducted the project with security cleared operatives to allow effective processing through the security for the Dockyard. We also used our experience from other Dockyard projects to competently manage deliveries and transport movements through Dockyard security for all logistics associated with our elements of work on the project.
There was a live steam main running alongside the building which, as instructed by the client, was to remain in place and not be damaged in any way. This steam main was both above and below ground. Below ground the steam main was protected by steel plates and above ground it was protected by scaffolding erected by our approved scaffolding sub-contractor.
The scaffold incorporated working lifts and the brickwork adjacent to the steam main was removed by hand methods with brickwork being deposited into the confines of the building. Operatives used sledge hammers and hand-held breakers to demolish the brickwork and downloaded brickwork into the confines of the building.
Prior to this commencing an exclusion zone was formed internally within the building in order to ensure no personnel approached the material drop zone. Mechanical demolition of the building commenced on the workshops, with access for the
excavator through a roller shutter door into the workshop. The excavator commenced by removing the third bay of the workshops, this allowed demolition to progress south to north.
Once inside, two excavators demolished the previously stripped-out two-storey offices by means of grapple and pulveriser attachments. Travelling-cranes were cut down by two machines, one holding the crane/steel, whilst the other sheared to isolate the section. The isolated section was then lowered to the ground floor slab. Once the mechanical demolition was completed, small column stumps remained where the machine had been unable to shear the columns flush with the ground floor slab. Qualified operatives therefore used Oxy/Propane burning gear to hot cut the column stumps flush with the ground floor slab, leaving the slab free from trip hazards.
All arisings from our activities were loaded away progressively throughout the project and the project was completed on time.