Experience of inter-chamber pillar mining after consolidation of the primary chambers' backfill

Abstract

In 1966 at the Kaula-Kotselvaara mine of the Pechanganickel Combine, experimental work was carried out on the development of an inter-chamber pillar located between the walls of the cement-reinforced backfill. Pilot works were carried out in a 6-8 m thick section of the ore body with a dip angle of 26-30°. The intervening rocks - phyllites - are partially broken by transverse fractures. In general, the ore and rock are stable. Ore strength coefficient is 8-12, rock strength coefficient is 10-12. Volume weight of the ore is 3.2 t/m³ and of the embedding material is 2.8 t/m³.