St John of God Subiaco

Project Information

BACKGROUND

St John of God Subiaco Hospital is embarking on a major redevelopment to ensure the campus remains a world-class private hospital of clinical excellence into the future. The redevelopment will be in three stages, currently in stage two and includes a refurbishment of the main hospital entrance and lobby, featuring a new reception, updated flooring, and digital signage. It also involves replacing patient lifts, upgrading the multi-storey carpark, and enhancing engineering services with a new energy and water plant, along with relocated power infrastructure. The project will also improve community connectivity and expand clinical capacity to meet future healthcare demand.

CHALLENGE

Reduce pile deflection when excavating to the desired basement level of this new build. Keller Australia completed the CFA piling around the perimeter of the excavation area. The use of shoring wasn’t feasible as the cost and timeframe of the build wouldn’t allow this solution, grouted anchors were a potential solution however these would be going into neighbouring properties and under public roads therefore the local government didn’t approve this method. Hulk Earth Anchors were approved as the tendon can be removed once the build is finished leaving only a small anchor head.

SOLUTION

Keller Australia’s solution was to use the largest of the Hulk Earth Anchors range. Earth Anchor Systems started to install HG 320 anchors however the soil was too dense in certain areas, the team decided to go case by. case and use the HG180 when the stress on the machine was too great. The design was completed by Keller Australia and the installation team followed these plans to achieve the desired solution of 109 anchors. A variety of installation angles were required to miss existing services. Each anchor was installed to a depth of 8 metres and then proof tested to the required load, shotcrete was applied to the pile face and the team used 1.2m 1.8 and a 5m steel PFC pair to lock off the anchors under load of 7 ton. The excavation was then be completed with minimal deflection and without delay. Once the concrete slabs are poured the Earth Anchor systems team will remobilise and remove the 8m CTB tendon leaving only the sacrificial anchor head in the ground with minimal soil disturbance. Multiplex required Earth Anchor Systems to promptly remobilise and remove certain pairs of PFC to avoid clashes with walls once the engineered had approved the load calculations.

PRODUCT

HULK HG320 8m CTB Tendon