Rehabilitation works to Port Botany’s Bulk Liquid Berths have been completed by NSW Ports.
The port operator reports that pre-stressed concrete beams inside the 1979-built Bulk Liquids Berth (1) had been exposed to the salty marine environment and investigations had show that the steel reinforcement and steel strands inside the beams were at risk of corroding. That could have caused a collapse.
The port operator installed a “hybrid anode corrosion” protection system which will protect the system against the marine environment for “the foreseeable future”.
Nearly 35,000 anodes were embedded into the concrete beams, along with remote monitoring and control capabilities. An “anode” is an electrode in which an electrical current enters a device. The anodes were energised for about 120 days, which arrests any corrosion in progress. Then, owing to underlying chemistry and physics, the anodes will corrode instead of the steel for as long as the anodes last. Installing sacrificial metals (such as zinc) on marine steel infrastructure is a common method of corrosion protection.
The $14 million project involved inspection, steel augmentation and concrete repairs to about 6,850 square metres of structures. Works also included the repair of dilapidated concrete and the spraying of a “silane coating” on the concrete surface for additional protection.
NSW reports that the project involved 76,000 total labour hours being completed over a 25 month construction period within a live 24/7 shipping environment with no unplanned disruption to shipping operations.
NSW Ports comments that Port Botany is NSW’s primary bulk liquid and gas port, handling 99% of bitumen imports, 98% of Liquid Petroleum Gas (LPG) imports, 90% of bulk chemical imports, 30% of refined petroleum fuels and 15% of the state’s aviation fuel requirements.