Distribution Centre

Castle Donnington, Leicestershire

One of our repeat clients presented an enquiry for a Ground Improvement solution to the foundations, external dock walling, and floor slab for a 320,000 sq. ft. single storey warehouse unit, with design loading specifications of 150kN/m2 and 60kN/m2 respectively.

The site is the former Castle Donnington Power Station built upon previous greenfield land. This posed significant challenges to foundation design, with remnants of concrete cooling towers still present and significant industrial contaminants identified. The natural ground conditions comprise of a varying layer of mixed made ground, overlaying clay and gravel deposits which in turn were underlain by bedrock of sandstone.

Prior to our arrival, intensive remedial works were carried out to prepare for the new development. This left areas of the site with highly compacted fill which were too hard to penetrate solely with our Vibro equipment.

To overcome this, alongside our fleet of Vibro rigs we also operate specialist pre-auger machines. These rigs allow us to ‘pre-bore’ areas of difficult ground, allowing the Vibro probe to penetrate the ground and form a full column.

Due to the large scale of the project, we utilised two of our largest class-leading ABI rigs and one of our pre auger rigs, to install over 6700 columns in only 53 days, to an average depth of 3.8m with a maximum of 8m.

As with all our projects, our teams undertook regular and diligent in-situ testing comprising of plate tests and dummy foundation tests to ensuring the proper performance of the columns, and to confirm that they meet the settlement criteria of the design specifications.

On a scheme of this size, the use of Vibro Stone Columns instead of traditional piling methods saved our clients costs in excess of a million pounds, with no reduction in performance or durability.