Production and Placement of Xblocs®, Gorgon, Western Australia

More than 40,000 Xblocs® form the protection of the causeway for the materials offloading facility (MOF) for the Gorgon LNG project, located at Barrow Island, just off the coast of Western Australia. The Xblocs® have been produced, stored and quarantined to meet the strict Australian quality requirements at the BAM Indonesia precast yard in the Port of Cigading, West Java. The Xblocs® were transported by barge to Barrow Island, where they were placed with land based equipment.

BAM Indonesia’s Precast Yard

The permanent precast yard on West Java caters for the production, storage and quarantining of precast concrete units, whether it be reinforced concrete units such as jetty elements or gravity blocks, or concrete armour units, including the Xbloc®. Precast concrete elements can be loaded from the nearby materials offloading facility. The permanent set-up of the yard garantees a quick response after order, which minimises delivery time for our clients.

Placement

After the production and quarantine in BAM Indonesia’s precast concrete yard, the Xblocs® were shipped by barges to Barrow Island in Western Australia. The offloading of the Xblocs® was done with front loaders equipped with hydraulic clamps.

The aforementioned total number of Xblocs® were placed with land based equipment. The total length of the MOF was 2.5km and the design included a breakwater at the edge of the structure.

The placement of the units was executed by the Contractor Companies Thiess and Boskalis. Placement was executed by means of crawler cranes or excavators provided with rotational hydraulic clamps in order to facilitate the orientation, when placing the units.