NOOSA - THE PROJECT

The Rise Apartments in Noosa comprise of 45 up market apartments with 2 separate areas for underground car parking. The larger of these (180m long), is two storeys in height and required a 10m deep excavation into the side of a sand hill.

The Challenge
Was to retain the sand hill. Due to the absence of rock, rock anchors were not feasible and permanent soil anchors in sand was inappropriate due to long term creep and subsequent movement. The geometry of the building and the siting of the larger carpark eliminated all the traditional approaches of load transfer of the retained hillside via shear walls throughout the structure into areas of excavation where active pressure could be mobilised to provide resisting forces.

The Solution
The lateral loads applied to the retaining structure were transferred to the foundations using portal frame action, thus taking advantage of the stiffness of the blade columns between car-parking bays.

Having transferred these loads into the foundations the magnitude of the applied forces were of such an order that of all the conventional means available, raking piles was the only possibility - this proved to be excessively expensive and impractical.

A unique solution to the problem was developed by creating a series of underground shear walls interconnecting the column bases (19 off each 20m long and 4m deep). These shear walls were designed to develop sufficient skin friction to resist the applied loads. This unique approach contributed significantly to making the project viable.

Click here to download a copy of our Brochure