- Mainly fractured dolomite
- Unstable layer from 1,1 to 1,5 meters
The open pit mine is located in Aykhal, Siberia as part of the Aykhal production site - one of the world-leading diamond producing companies ALROSA. Aykhal is situated in the permafrost region – that is why operations in the open pit area are impossible during 2-3 months of the short summer time: Many rockfalls occur as a result of melting permafrost slopes. However an underground mine is operating and trucks are permanently using the portal to the quarry.
Some conventional wire mesh was widely used at this spot until now to safeguard the portal. As this mesh did not provide enough safety and has to be changed every 2-3 years. Alrosa decided to test Geobrugg state-of-the art technology.
One of the challenges was the delivery of material and drilling machinery to the site: In winter time you may use the ice road which runs along the river Lena.
In the summer material has to be delivered by ship, what takes 1.5 months from the European part of Russia to this site. In the end the installation had to be carried out during the short period when the temperatures were above freezing which is from mid of May to mid of September.
For the protection solution TITAN 40/16 nails with TECCO G65/3 mesh and P33/50 spike plates were used. In total 1400 m2 were stabilized. The pure installation time without delivery times was one month.
The berms are subject to heavy erosion due to the melting permafrost. TECCO G65/3 then will stabilize actively the berms of the open pit mine in future.