Karekare Beach Residence, Sand Dune Stabilisation
Location: Karekare Beach, Auckland
Project Value: Undisclosed
Sector: Residential, 3 Waters
A steep site (30-35°) on sand does not typically constitute a viable building site. The challenge was to determine a suitable foundation system for the site which included depths of loose sand in the order of 10 m in places.
GWE carried out a series of hand auger and machine drilled boreholes in conjunction with detailed slope stability analysis to inform foundation and slope stabilization design. A deep foundation system with tie backs to provide adequate resistance against lateral loads was selected. The resulting design was confirmed by the structural engineer implementing micropiles, up to 12 m long, that extended
into rock. The design was externally peer reviewed and approved by Council prior to Building Consent being issued.
In addition to the micropile foundation/tie back system, continuously advanced and cemented retaining walls were constructed along the upslope of the development to protect the neighbouring property.
- Geotechnical site investigation, on-site wastewater/ stormwater design and management.
- Geotechnical design analysis to confirm stabilisation options.
- Earthworks and micropile foundation and tieback installation supervision.
- Geotechnical design checks during construction monitoring.
- Coordination with designers site builder and micropile/tieback contractor.