OPEC Systems was delighted to assist deconstruction experts Liberty Industrial in the demolition of wharf structures located at Northshore Hamilton after engineering assessments indicated that the structure was unsuitable for ongoing industrial wharf use.
The wharf demolition involved the removal of approximately 15,000m2 of concrete deck structure and sub-structure including timber bearers, joist and concrete head stocks plus edge beams.
Given the dilapidated nature of the wharf, an approach utilising large capacity crawler cranes was devised to satisfy the tight scheduling requirements dictated by Economic Development Queensland.
In addition to the deck and sub-structure removal the project included the removal of over 1900 piles. The piles varied from timber with concrete sleeves to hollow and concrete filled steel piles some of which exceeded a metre in diameter.
Given the requirement to ensure the ongoing stability of the existing seawall and river bed, the piles had to be cut a metre below the existing seabed height to ensure the ongoing stability of the existing seawall and river bed and ensure safe navigation through the area. OPEC was engaged to do this and we deployed three full time dive crews that utilised a range of innovative underwater cutting tools and techniques.
In order to remove the 1900 piles efficiently OPEC deployed teams dedicated to specific techniques. The techniques included underwater dredging to expose the pile a metre below the sea bed, specialist riggers to safely sling the concrete protective sleeves which existed on the majority of the piles, underwater hydraulic chain saw to cut the 1700 timber piles and underwater diamond wire cutting equipment to cut the steel and concrete piles.
Stringent procedures and controls were put in place to ensure no discharges into Brisbane River, including dedicated booms and silt curtains for the project.
All suitable timber was recovered and recycled, with select pieces being used in future landscaping and structural architectural features across the Northshore Hamilton development site.
Article about OPEC and the Diamond Wire Saw in Subsea UK News