In 2017, Aarsleff Ground Engineering were awarded the contract to provide piling for a new scheme set up by one of the largest electricity and gas transmitters in the UK, the National Grid. The Richborough Connection scheme is part of a new 20km high-voltage overhead transmission line from Richborough to Canterbury. The line will connect up to new power sources, including a new subsea power supply from Belgium to the coast of England.
Aarsleff was originally awarded the contract by the Carillion Eltel Joint Venture, until the collapse of Carillion in early 2018. As a result of this, the contract was taken over by J Murphy & Sons to form the Murphy Eltel Joint Venture (MEJV).
For the project, Aarsleff drove 950No. 400mm square precast concrete piles utilising four of its Junttan and Banut rigs, driving piles from 6m to 30m in length. The challenge of the project was due to the 60 pylon sites across 20km of Richborough countryside.
Aarsleff’s Senior Contracts Engineer, Simon Cottington, who oversaw the project commented,
“Making sure our driven piling rigs and pile deliveries were able to get to every pylon site proved to be a challenge. To access some of the sites we needed to dismantle one of our Banut piling rigs, removing the hammer, leader mast and counterweight.”
Along with the precast piles, Aarsleff installed 563no. micro piles, which ranged from 10 metres to 25 metres, and 96no. bottom driven piles. These piles were utilised at some of the pylon sites due to restricted access and low overhead cables.
“The programme for this project was also challenging. Keeping track of the deliveries, pile testing and rig movements whilst keeping to the schedule led for some testing moments, but I am pleased to say we were able to deliver a smooth and flexible solution for the Murphy Eltel Joint Venture.”
Over the 11 months on site, Aarsleff installed piles for 60 pylon bases and two temporary access bridges.