Palmwoods Village – MagnumStone™ Wall

Located along Sunshine Coast’s North Coast railway line, the town of Palmwoods provides a wide range of convenience goods and services to the surrounding rural communities. A new commercial property including a shopping centre and supermarket was to be developed, which included an original retaining wall design of a grouted rock wall with a piled footing, but the highly unstable ground within this low-lying swamp area meant their current design suffered from global stability issues.

Seeking an alternative solution, engineers Covey and Associates turned to Cirtex and the MagnumStone system.

DESIGN

Cirtex worked closely with Covey and Associates to design a curved MSE retaining structure using both StrataGrid reinforcement geogrid and MagnumStone extenders where a gravity retaining wall was better suited.

Approximately 150 metres long and retained up to 4.5m, the lower section of the retaining wall addressed the issue of global stability by using a modified StrataGrid section compared to a standard design. This also allowed for a more vertical wall, gaining more ground with less cost by removing the need for piling.

INSTALLATION

Before construction could begin, issues with the founding soils meant some ground improvement was required directly beneath where the MagnumStone blocks would be placed. A 1.5m deep section was replaced with high quality road base to give the wall a solid foundation.

Built using compacted layers of engineered fill, the near vertical MagnumStone wall will have a garden placed on top as a boundary edge, giving the community of Palmwoods an attractive, stable car park area to their new regional supermarket.

The MagnumStone system provided the following benefits to the project:

• Can be built using both MSE and Gravity designs without changing the face of the wall
• Removes the need for costly piles and large machinery on site
• Safe and efficient to install