Project Overview
To accommodate a new 170m long vessel, Citic Pacific required the port’s berthing pocket to be deepened from 10m to 11m. The existing rock revetment had been sized for smaller vessels and needed stabilisation.
MMA's Solution
MMA designed a bespoke stabilisation and scour solution. The design was completed in house and scale testing of the solution was completed at the University of New South Wales’ Water Research Laboratory. A total of 3000m2 of mattresses were fabricated, transported by road to the remote site and installed.
Technical Details
The proposed solution, which consisted of a combination of MMA’s CoastMattTM and plastic shell articulated concrete mattress (ACM) products, all interlinked and laid over the existing rock armour revetment like a blanket to stabilise it and protect it from scour, underwent scale testing at the University of New South Wales’s Water Research Laboratory to confirm that the design would perform as required as well as to fine tune the final mattress arrangement.
The mattresses were then fabricated by MMA in Karratha, WA, after which they were transported by road to Cape Preston and stockpiled before being installed by the marine contractor.
MMA also designed and fabricated a 12 metre long lift frame to allow TAMS to deploy two mattresses at a time thereby significantly reducing the installation time. The works were completed in record time and with minimal disruption to normal port operations.
Key Equipment
- CoastMattTM - 6 x 2.5 x 0.4m - 84 units
- Articulated Concrete Mattress - 6 x 2.5 x 0.42m - 119 units
- Installation frame
MMA Innovation / Value Added
- Design of mattresses acting as a blanket for stabilisation and scour protection
- Installation frame deploying two mattresses at a time