The new dock will service the next generation of RORO vessels for Stenaline. Quinn Piling’s expertise in Marine engineering was called upon by Farrans to deal with this very challenging project.
Temporary Works Piles
The first phase of the works involved installing five 610mm diametertemporary works piles to 26m depth to support the temporary works frame. This frame was required to support the piling rig to allow it to install two 1,219mm diameter fixed bridge piles. This temporary platform was needed because of access restrictions for a jack up barge.
The second phase of our works involved removing the temporary works piles and frame and installing two 1,200mm diameter piles on land using conventional rotary techniques to 30m depth.
Working from Jack Up Barge
A further twelve vertical 1,219mm diameter piles were installed for the fixed bridge from a jack up barge to depths of 30m. These included a five-metre rock socket.
Raked Piles
Four 1,219mm diameter piles were installed at 1:3 rake to a depth of 49m. These included a 22m rock socket. In order for these four raking piles to be installed a specially developed guide frame was constructed. This required two vertical piles to be installed onto which a pile gate frame was fixed. This allowed the new piles to achieve the 1:3 rake whilst also supporting a temporary works frame for the piling rig.
2.25M Diameter Mono Piles
Once the fixed bridge works were completed the rig was mobilised to install two mono piles.
A 2.5m diameter, 30m long temporary casing was installed with combination of vibrating hammer and advance boring. Then the pile was advanced using 2.4m auger to 16m below seabed (achieving a 10m long rock socket). The 2.25m diameter mono pile, 41m long, was then craned into position and the annulus in the bedrock was grouted using a bespoke system designed and constructed by Quinn Piling.