Client: Ullapool Harbour Trustees
Engineer: Wallace Stone LLP
The project was for the extension of the existing pier to accommodate a new passenger ferry. The works included preparation of the underwater foundations and installation of a reinforced concrete caisson (constructed off-site), extensive shot blasting, remedial works, painting of the existing pier structural steelwork and provision of new parallel motion fenders and quay services. RJ McLeod developed a temporary works design to strengthen and fit out the caisson for towing – this allowed the controlled installation of the caisson to 25mm tolerance in a single overnight shift between ferries – and to resist berthing loads from the new ferry in the temporary case to allow early use of the berth whilst the deck structure and services were completed in situ. The works were carried out under NEC 3 Option A conditions of contract.
• Working within an operational harbour accommodating passenger ferries, freight ferries, fishing boats and fuel deliveries – works carried out around ferry timetable with no disruption permissible
• Reinforced concrete caisson constructed off-site at Inchgreen Dry Dock in Greenock on the River Clyde to be subsequently towed to Ullapool Harbour
Principal Elements included:
Dredging works 700m3
Infill of rock bund for caisson foundation 1,600m3
Shotblasting and Painting 1,319m2
Concrete deck works to caisson 500m3
Reinforced concrete caisson 4,100t
Rock infill (on delivery of caisson) 13,000t
Underwater concrete foundations 350m3
Sheet piling 200m2
Bearing pile fenders 2 no.
Passenger Access System piles 4 no.