Rocla’s Adelaide facility recently supplied around 300 specially manufactured box culverts to the Techport Australia shipbuilding hub.
Techport Australia is being developed by the South Australian Government as a naval industry hub to support the Navy’s Air Warfare Destroyer (AWD) project. ASC (formerly the Australian Submarine Corporation) is building the destroyers at its base in Osborne, in Adelaide’s northwest, where it built and is now maintaining the Navy’s Collins class submarines.
The SA Government is investing more than $300 million at Techport Australia to support ASC and attract other shipbuilding and repair opportunities. Techport Australia will feature common user shipbuilding facilities, including Australia’s largest ship lift, a transfer system and wharf, plus a 35-hectare supplier precinct for sub-contractors, as well as a commercial and education precinct.
Rocla manufactured the 1800 x 2400 box culvert inverts in 2.4 metre lengths for MDBEJV to construct a services duct. The tunnel runs for some 700 metres under the perimeter of the massive pavement of the common shipbuilding area, where the destroyers will be assembled. To ensure the tunnel was watertight, membranes were placed between the box culverts, which were jacked together under 5 tonnes of pressure.
The service tunnel carries high voltage power, compressed air and potable water, as well as seawater for cooling and fire fighting. Rocla manufactured special “upside-down” moulds to make the culverts, which had to be poured legs-up (rather than legs-down) with starter bars protruding from the top to connect to the pavement slab. Special concrete was also required to cope with the marine environment and the acid sulphate soils at the site.