Construction has been known to borrow ideas from the motor manufacturing industry, usually in terms of processes or how a company is run.
But the North Liverpool Academy has taken this further and based some of its design on part of a car – a Jaguar door handle.
The academy is being built by Wates and while the rest of the building is a simple beam and column build, it is a steel structure shaped like the car door handle, running through the length of the building, which stands out.
The ‘handle’ is not symmetrical – it has a curved steel roof and a ‘head’ at the west end and ‘tail’ on the east side which both curve at different angles. At three storeys high, it will stand a floor above the rest of the building. It is 140 m long by 15.6 m wide and is made of 350 tonnes of steel.
The contractor got started on the main blocks of the building and then moved on to the handle.
“We started with the north and south parts of the building while the design was being finalised. The structure was modelled by Atkins and adapted by specialist contractor Billington,” says Wates construction manager Wesley Allmark.
Fabrication drawings were then made for each piece of steel. The sections of steel were welded then delivered to site in the order they would be needed. The connections were quite a challenge and it took time to analyse the loads which passed through the structure to make sure they were the right strength.
The most technically difficult part was getting the curves of the head and tail sections as smooth as possible.
“Because they are so curved, most materials won’t bend to the shape. It also curves in three dimensions and it is difficult to get the materials to follow that,” says Mr Allmark.
To prevent the sections faceting, three layers of single-ply wood membrane were applied to the two sections and finished with a plastic silver-coloured membrane coating. The main body of the handle only needs two layers of ply to get the curve correct. Ply was chosen over kalzip as it’s easier to shape to the right radius.
Bowstring trusses support the main floors and above these are curved multi-radii roof members which make up the main part of the handle. Curved tubular purlins and sheeting rails will help give the external shape on the head and tail.
The hoops of the steelwork are in a sequence of perpendicular tangential arcs which give a smooth shape and help make the handle buildable.
Most of the roof is constructed using 200 mm metal decking sheets fixed to the hoops.
To provide a smooth continuous surface to fix these, workers welded steel plates to the top of the circular hollow section steel supports. But on the head of the handle, contractors are installing 48 mm decking sheets to get the tighter curves.
Why build this shape? Mr Allmark says: “Academies are meant to be inspirational and the Jaguar door handle provides the concept that will hopefully inspire pupils.”
• The total amount of steel used for the school is 900 tonnes – 350 of which are used for the handle
• 30,000 m3 of material was cut and fill
• The foundations are pad through sandstone
• The site is 5 ha with about 14,000 cu m floor area
• 97 per cent of waste has been recycled, with about 5,000 m3 of hardcore reused