Kingston Heights

Case Study

Kingston Heights is a £70 million mixed-use development in the Royal Borough of Kingston upon Thames in southwest London, United House are main contractors on the project which will comprise 136 residential units, including 80 private apartments, 56 affordable homes, and an up market 150 bedroom hotel with meeting, banqueting and conference facilities.

Banagher Precast in conjunction with Charcon supplied and installed precast for the first phase of the project which involved the technically-challenging encapsulation of a UK Power Networks substation within a steel-lined precast concrete ‘box’ approximately 200 metres long, 38 metres wide and four storeys high. The enclosure was constructed using pre-cast concrete for the columns, bridge beams and infill panels, and required a 1,200 tonne mobile crane to lift the 50 ‘u’ shape beams that will form the podium deck, with an average length of 34 metres, a depth of 1.7 metres and each weighing 70 tonnes, into position. The works were meticulously planned in key stages around pre-arranged transformer outage times starting in Spring 2012 to ensure there is an uninterrupted supply to 100,000 UK Power Networks customers and completion before Olympic deadlines.

The original design had the main spanning elements as 1.5m deep structural steel girders. Our proposal to use our unique W beam design as an alternative was welcomed by the design and construction team as it solved many of the inherent design obstacles. These included fire resistance, blast resistance, durability and maintenance requirements. These coupled with a more cost effective solution which could be installed during outages in one clear span section gave the client and UK power networks the confidence to use our system.

The first stage of this project is essentially a large civil engineering project. The beams used to span the 35m over the transformers are the same beams we have
used on road and rail structures throughout UK and Ireland. The final loading on the deck will be 3 storeys of apartments which is broadly equivalent to full traffic/train loading

The project is an excellent example of how long span Concrete bridge beams can be delivered and installed to a city centre location and meet all the challenging design criteria for a complex structure. The W beams sit on designed elastomeric bearing pads, the deck slab is formed with Fibre and GFRP rod reinforced concrete slabs which form a permanent shutter to the insitu slab as per bridge deck design. Other unique design features are Super Y Edge Beams stitched together using insitu concrete diaphragms to give clear spans of 35m in one direction and heavy duty prestressed wideslab giving 8m clear span in the other direction.

The structure is made up entirely of precast comprising over 1000 elements from columns, wall panels and beams including two 25m high large Box section Vent shafts.

There are certain immovable objects which can cause problems for Civil and Construction projects for highway and rail routes, a rail line itself can be a difficult obstacle to transverse and similar to a transformer substation can only be worked on during outages. The project was completed in 5 stages during agreed outage periods with UK Power networks. It was finished on time and budget to satisfaction of all parties.