Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more

On course for the Champ

Construction of Britain's first banked raceway in almost 100 years is presenting major engineering challenges. Mark Hansford reports.

Northamptonshire is braced for a new form of motor racing, with the inaugural British leg of the CART FedEx Championship at the new Rockingham Motor Speedway. But by the time the green flag flies at 12:30pm on 22 September, the track's biggest race will already be finished.

Since site work on the £50M project began in May 1999, design and build contractor Morrison Construction has been battling against atrocious ground conditions, last minute design changes and shocking weather.

Back on track, but with the wearing course yet to be laid, the grandstands mere skeletons, and the grand opening on 26 May approaching fast, Morrison knows this is no time to ease off the throttle.

The site - an abandoned quarry in Corby - caused headaches right from the start.

Used first by British Steel as a source of iron ore and then as a spoil depository, it left Morrison with remnants of excavated sandstone and ironstone and tonnes of backfilled boulder clay.

After four years of planning and design, Morrison's first move on site was to surcharge the entire area with 3m of clay and spoil. Some 300mm to 400mm of compaction was achieved in just three months.

It was at this stage that the first of two major problems hit.

Racing organiser CART announced that all circuits need to be at least 1.5 miles in length.

At 1 mile, Rockingham was not going to be long enough.

Tight site boundaries - with a river, two roads and a landfill site to the west effectively barring expansion - meant a redesigned layout was the only option. The result was an unusually 'fat' circuit and the grandstand shifting 90degrees to the west.

With the new configuration decided, work began on shaping the circuit, removing 1.6M. m 3ofearth in the process, before moving on to lime stabilisation.

However the operation coincided with exceptionally wet weather, and with dry conditions essential for lime stabilisation, the whole scheme was again put at risk.

'We went through three hellish months, ' says project manager Ahmed Mubarak. 'But we're now back on programme.'

The track base was trimmed to a tolerance of +/-10mm and heavily compacted to allow the asphalt thickness to be minimised. The final combined thickness of road base, base and wearing course will be just 160mm, laid to a tolerance of +/-1.5mm per 30m.

Colas was selected as surfacing contractor because of its expertise in similar projects.

Colas UK laid Toyota's test track, with its 35degrees banking, and sister company Barrett Paving has worked on eight ovals in the US.

To meet the demands for skid resistance, spray suppression and tyre wear, Colas chose bitumen from Shell Bitumen with added polymer modified binders to ensure low stiffening points.

The wearing course has been designed for a 10 year life, with the whole surface designed to last a further 10.

With banking of up to 7.9degrees, a traditional paver was out of the question. Instead, Colas opted for a smaller 60t paver with a buggy to shuttle asphalt from a mobile mixer located on site.

The paver was modified to include high compaction screens to reduce the need for rolling. At 225t/h, the mixer is the largest in the UK, and has produced 50,000t of asphalt in laying 126,000m 2of track.

The buggy has also allowed Colas virtually to eliminate joints, with the entire oval circuit laid as four parallel strips.

With 11 hours of daylight needed for each seamless strip, winter work switched to the 'in-field' international circuit.

But this week Colas aims to move back to laying the wearing course.

By the end of the month both oval and in-field sections should be complete. Oval racing in the UK has arrived.

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Please note comments made online may also be published in the print edition of New Civil Engineer. Links may be included in your comments but HTML is not permitted.