Rock-socket piling supports ferry terminal upgrade in challenging Scottish ground conditions

We were commissioned to provide specialist drilling and piling works as part of the enabling works at Kennacraig Ferry Terminal. The scope included installation of 28 grouted rock-socket piles, designed to support new ferry berthing and mooring arrangements for future vessel operations.

Drawing on previous local project experience, we identified that ground conditions were likely to be more variable and harder than indicated in the original site investigation. To mitigate this risk, the team selected tungsten carbide button cutters to improve drilling performance and wear resistance in hard metamorphic rock.

Operations were carried out using the MDR-012 drilling rig, supported by a complete hydraulic power unit and umbilical system, with under-reamers configured between Ø1,100 mm and Ø1,400 mm. Full factory acceptance testing (FAT) and site acceptance testing (SAT) were completed before offshore operations commenced, helping ensure readiness and safe delivery.

Throughout the campaign, close collaboration with our client George Leslie enabled design revisions to align with actual geotechnical conditions encountered on site, while localised drilling and grouting techniques helped minimise seabed disturbance in the shallow coastal environment.

• MDR-012 drilling rig with HPU and umbilical system
• Tungsten carbide button cutters for hard rock drilling performance
• Weighted Bottom Hole Assembly (BHA) fitted with a Ø1,100–1,400 mm drill bit with under-reamers for rock-socket pile installation
• Ø1,320 mm gripper can for operational stability
• Full FAT and SAT testing programme before mobilisation
• Localised drilling and grouting methods to minimise seabed impact