Electricity Pylon - Mechanical Access

Exceptional height of the pylon, coupled with its light-weight construction and exposed riverside location

Scope

The 193 m tall Electricity Pylon at West Thurrock, East of London is the tallest structure of its type in the UK. Constructed in the 1960’s and owned by the National Grid, the pylon carries the power-lines for the Thames Crossing near Dartford.

Challenge

The Electricity Alliance East (an Alliance between National Grid and Balfour Beatty) approached Brand to devise a safe method of delivering operatives, tools and materials to a work platform located two-thirds of the way up the structure for essential electrical and structural maintenance work. The exceptional height of the pylon, coupled with its light-weight construction and exposed riverside location placed significant restrictions on the access supplier. Our solution was to use a specially adapted, 120 m high mast climbing work platform (MASTCLIMBERS™) erected through the centre of the pylon.

Performance

Space within the tower was restricted, especially near the top where it narrows to just 5 m x 5 m. Brand therefore used a single masted unit with a platform small enough to travel up through the central frame to the platform. A key advantage of the mast climbing system is that it can be progressively erected from its own platform - without any additional access.

To support the slender lattice mast, Brand designed a special tie to take the weight and transfer the load safely to the pylon’s light-weight structure. Design engineers calculated that there is a need to use an unusually large number of ties to ensure the rigidity of the mast. Therefore a bespoke tie with 38 connection holes was designed.

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