Careys Building and Civil Engineering was the Civil Balance of Plant (CBOP) design and build contractor for the Mount Lucas Wind Farm project on a Bord Na Mona site of approximately 630 hectares . Our team undertook the design and build of 21km of on-site access roads, and 29 hardstands for the windfarm, which now provides renewable electricity to 45,000 homes.
Our team identified multiple challenges and risks through surveys undertaken during pre-construction. Careys worked with the client and WTG supplier foundation design teams value engineer and the 28 WTG foundation designs for the site, resulting in the construction of 12 spread foundations and 16 compression piled bases, designed for a safe working load of 1006kn. This piling was particularly complex, so a team devised two design proposals which were tested proven through additional site investigations. The result was the construction of 16 piled foundations consisting of between 52 and 84 precast piles each.
Each turbine foundation consisted of a monolithic 640m3 concrete pour carried out over 10 hours. Each pour consisted of 6 different concrete mixes and slump classes, and 70% GGBS was used in the approved design mixes to control the heat of hydration in the mass pours. The concrete element of the works was the subject of a four page feature in a Concrete Magazine special on sustainable construction.
Design development continued throughout the project. This enabled our consulting engineer partners to develop a site drainage plan.
In addition to these works, our team carried out all site clearance, setting out, and construction of roads, in addition to construction of all hardstandings and excavating peat and underlying material to achieve the minimum California Bearing Ratio (CBR) suitable for the road construction.
The project included the upgrade of 6km of local regional roads and the construction of Philipstown Bridge over the Philipstown river to accommodate the wind turbine component deliveries to the project.