Complete Access installs major power line protection over M25

Scaffolding contractors, Complete, have installed over 200 tons of scaffolding to successfully complete a huge challenging power line protection scaffold over the M25 motorway.

The Barnsley based firm, Complete Access Specialist Contracts Ltd have finished a substantial large-scale system scaffold with a protective netting spanning the busy M25 motorway below.

Working for Interserve Industrial on behalf of SSE, Complete erected the scaffold to provide protection to the M25 motorway between junctions 16 (M40) and 17 (Rickmansworth) while refurbishment of the power line are carried out overhead.

The scaffolds are 154m long, due to the angle at which the power line crossed the motorway, stand 9m-13.5m tall with protective netting spanning 82.0m over the carriageway. The scaffold design, approved by M25 agents Connect Plus M25 and Highways Agency, was produced to cope with winter loads; considering the potential for ice on components and snow on platforms and net producing massive tensile loads in the catenary support wires. As a result, bay sizes were reduced, more than doubling the number of frames throughout. Specially made heavy duty 12mm diameter wire rope catenaries were required, a total of 550 stay wires and ground anchors were installed for stability and a total of 880 half-railway sleepers (60 tonne) were used for foundations in order to distribute the scaffold leg loads .

The scaffold was formed from approximately 200 tons of Layher all round system scaffold and took 12 men 4 weeks to erect from start to finish. A complex traffic management scheme involving the simultaneous total closure of both M25 carriageways, junction 17 on-slip road and both Eastbound and Westbound M40 link-roads was necessary to install the netting, which was coordinated between three separate TM contractors, Connect Plus M25 and Buckinghamshire County Council, and took place over 3 consecutive evenings.

A spokesperson for Complete Access Specialist Contracts Ltd said:

“This item in particular presented great challenges, not only in design but also in coordination and interface with highways’ and other third parties. The sheer scale and amount of material in the job is testament to the resolve of the operatives involved in the erection and netting. We believe that it’s the first time M25 has had this kind of protection scaffold installed. Complete have worked on some major crossings in the uk which include the A1, M1, A9 in Scotland & M40 to name a few. The M25 has been the most difficult to date for installing netting taking 15 men 3 consecutive night shifts to install.”