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

Neither fish nor fowl

Taylor Woodrow used modified rotary equipment to form short CFA piles on a Staffordshire river strengthening project.

DURING PILING for the Environment Agency's Burton-upon-Trent flood alleviation scheme in Staffordshire, Taylor Woodrow Construction's spec- ialist geotechnical operation, Foundation Engineering, had to overcome a number of logistical and conceptual problems.

Work was divided into three sections, the biggest challenge being the middle section, which involved building a new river wall. Two pile types were initially proposed, 900mm diameter rotary bored king piles extending down into weak to moderately strong mudstone and 600mm diameter CFA piles, only 2.5m long, protect- ing the river bank in-between.

However, work was complicated by an existing low-level river wall. For stability reasons, the mast foot on a CFA rig needs to be placed immediately beside the pile position, which meant the rig would have had to straddle the low wall.

And while rotary piling rigs, which are more stable on their base carriers, could work over the barrier, they were not economic for the shorter, 2.5m long protection piles which made up the majority of the job.

Instead Taylor Woodrow pumped concrete down the centre of the kelly bar so that it could form 'hybrid CFA' piles using modified rotary equipment mounted on a Casagrande C50 base carrier.

Taylor Woodrow estimating manager Mike Tate said: 'Working in close liaison with main contractor May Gurney (Construction) and consultant Sir William Halcrow & Partners, positional tolerances were resolved on a revised config- uration that satisfied both build- ability and design requirements.'

The most southerly and final section is due to finish next month. Here piling is being carried out from a berm pushed out into the river to avoid the river wall.

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.