The Spire London/Hertsmere House project is located in Canary Wharf, Docklands, comprising the demolition and clearance of a 5-story former office building down to ground floor level, installation of temporary works, demolition and clearance of the basement box, removal of foundations, pile probing, construction of piling platform and piling plant foundations, construction of capping beams, reduced dig to formation and bearing pile break down.
The project is bordered by restaurants, bars, apartments and the Museum of London Docklands to the north, residential moorings on North Dock to the east, Credit Suisse to the south and The Tune Hotel to the west. Additional consideration had to be given to the Cross-Rail excavations being carried out underneath the site.
The site boundary was secured with a timber hoarding and the front elevation of the building adapted to form a drive in/drive out, off road, processing and loading area, minimizing disruption to local pedestrian, cycle and vehicle traffic.
The building was wrapped in an encapsulated scaffold and fitted with acoustic quilts on live working floors prior to demolition. These measures in tandem with water sprays greatly reduced noise and dust pollution.
Newsletters were distributed to neighboring properties and several pre-demolition presentation meetings were held, avoiding significant complaints and conflicts and ensuring that the works were completed on time.
All live services were made safe, the internal areas of the building were stripped, the roofs were dismantled by hand and the building was reduced, from top down, using small demolition machines.
An LV switch room and UKPN substation located in the basement, remained live throughout, and weather protection was installed to the ground floor slab.
An automatic pumping system was also installed at basement level as a further measure against potential flooding, prior to handover back to the client.
This phase was carried out in partnership with Bachy/Soletanche who adopted the role of principal contractor.
The site hoarding was extended outwards to accommodate the 2nd phase of the works and trees were removed from the perimeter to enable working space.
A listed wall to the SW corner and a commemorative arch to the SE corner were stabilized and protection measures installed.
Sheet piling was installed to the north and south elevations and the ground floor slab to Hertsmere House removed.
The basement retaining walls were demolished, foundations broken out and holes were broken through the basement slab and the bearing pile locations probed.
All site arisings were processed and the material used to construct a piling platform. A temporary R.C. base for Bachy’s bentonite plant was then constructed.
In the Autumn of 2017 we will return to site, following completion of the piling works, install an R.C. capping to the secant piling, remove the bentonite base, excavate the piling platform, remove the remaining basement slab, excavate a further 12,000m3 of material down to formation, install a blinding layer, then break down the bearing piles.
This will complete our works on the project.