myGeobrugg
The Kaikoura M7.8 earthquake caused widespread damage to the road and rail corridor for approximately 20 km North and South of the Kaikoura township. Over forty major slips inundated the road and rail with more than 750'000 m³ of material from source zones up to 500 meters above sea level. The highly fractured Grey Wacke means frequent future rockfalls and debris loads. The high rockfall frequency with some debris loading created the requirement for a Geohazard Solution that could arrest the rockfall but be strong enough to withstand the pressure loading from debris accumulation. The barrier was located on the old road, and access behind the barrier had to be maintained.
A 116 meters long, 4 meters high GBE-1000A-R was the selected system. The fixed post system has no upslope anchor ropes enabling easy access behind for clearance and maintenance. The net was upgraded to a SPIDER® S4-130 to withstand the pressure loading and increase the durability for frequent rockfall impacts. TECCO® G65/3 was selected as the secondary mesh to avoid puncturing failures from smaller high-velocity impacts.
Due to the highly fractured rock mass from the cut and cover tunnel construction, self-drilling anchors were required. Geobrugg Type III flexheads transfer the load to the bar anchors. The alignment had two downslope anchors due to the curved alignment and two support rope separations to allow maintenance on individual sections. SUPERCOATING and ULTRACOATING were used due to the proximity to the sea.
NCTIR and NZTA
Rock Control
Route/Rue
GEOBRUGG SUPERCOATING, GEOBRUGG ULTRACOATING