Bonestone Bridge is a vital link for traffic destined for South Kyle, Scotland’s newest onshore windfarm. Based in Dalemellington, East Ayrshire, the site will contain 50 wind turbines and associated infrastructure, bringing power to 170,000 homes and a further boost to the country’s net-zero ambitions.
Before preparatory work started on the £67m project, a refurbishment of Bonestone Bridge was necessary to make it suitable for the safe crossing of turbine-carrying vehicles to access the windfarm site. It led to it becoming the first project in Europe to combine the benefits of Sika’s Galvashield Fusion anode system and its CarboDur structural strengthening solution.
Bonestone Bridge’s refurbishment was carried out by contractor Concrete Repairs over a 600m2 area of the structure. The Sika Galvashield Fusion anodes system was used to protect and prolong the structural repairs. For its application, the anodes were inserted into holes drilled into Bonestone Bridge’s concrete surface. In situ, they provide cathodic protection to the corroding reinforced steel, thus preventing further damage to the surrounding concrete.
The anodes protect actively corroding steel for up to 30 years. This cost-effective benefit negates the need for future maintenance.
Sika’s CarboDur system comprises carbon fibre reinforced polymer (CFRP) plates strengthened the bridge to increase its load capacity. Installed at spaced intervals to the underside of the structure, the plates support its ability to withstand the long-term stresses caused by passing traffic.
The Bonestone Bridge refurbishment was completed in December 2020 in line with the client’s agreed two-month timeframe.