Troy Wheeler Civil Ltd
Thames Coromandel District Council
A significant landslip had occurred on the downhill side of the road from Colville to Kennedy Bay closing it to one lane. The integrity of the road was compromised, and the slope dropped steeply down to the sea. The challenge was to prevent further surface erosion, stabilise the surface, and blend in with the surrounding environment.
The geotechnical engineers from Opus International chose the Platipus® (ARGS) System for this repair. The key deciding factors included the proven and documented performance of the Pyramat HPTRM when used to preventing surface erosion while providing a higher tensile strength than that of steel mesh. The high tensile strength and extremely high resistance to UV along with the unique X3® fibres of the Pyramat HPTRM were required in this harsh marine environment where the matting will be exposed to salt spray and extended UV exposure.
The Platipus (ARGS) System is straightforward to install, however the nature of this site required Troy Wheeler Civil to use a secure rope access system. The Pyramat HPTRM was laid down the slope and pinned with Steel U Pins for intimate ground contact for vegetation growth. Steel cable Earth Percussion Anchors were then driven in at 1.5m centres and lock loaded to provide a frustum cone of reinforced soil.
Platipus® Anchors has over 30 years experience and has proven that they combination of Percussive Driven Earth Anchors (PDEAS®) and a high strength facing material to support the load generated by the PEDA will stabilize and prevent erosion in these applications.
Pyramat grass reinforcement systems allow the use of eco-friendly and aesthetically enhanced vegetated surfaces on steep slopes and swales where previously unsightly hard armour systems were required.