Eakring T-Pylon Test Line

Richard Pennock

Richard Pennock


Tel: 01423 276000 Email


National Grid


  • Desk Study
  • Topographical Survey
  • Ground Penetrating Radar Survey
  • Project Management of Site Investigation Works
  • Interpretative Report
  • Assistance in Design Process

New T-Pylon transmission tower ground investigations

In 2011 a competition was organised by the Department of Energy and Climate Change, the National Grid and the Royal Institute of British Architects to design the next generation of electricity pylons. The competition was won in October 2011 by a Danish company, Bystrup, who designed the ‘T-Pylon’.

CGL was approached by National Grid to undertake a site investigation on an area of land adjacent to the National Grid Eakring Training Centre to allow the subsequent construction of six T-Pylon test towers. It was planned for the new towers to be erected on large mono pile foundations to some 8m to 10m depth and that geotechnical investigation works were required to assess the ground conditions at each tower location to allow detailed design to be undertaken.

In addition, during the land acquisition process, National Grid also required a topographical survey and utility information for the route corridor to be undertaken. CGL supervised the intrusive works and identified Mercia Mudstone to be present directly below topsoil at the site which could potentially be problematic for installing monopile foundations.

CGL provided an interpretative report stipulating recommendations and comments on foundation design, together with a characterisation of any contamination at the site and recommendations in respect of waste disposal.

Given the innovative design of the T-Pylon and the associated ground conditions, CGL was also involved in subsequent design meetings with Bystrup acting on behalf of National Grid to provide geotechnical expertise along with recommendations for suitable techniques to drive the monopile foundations through the competent bedrock.