EFFECT OF DRY BACKFILL ON SUPPORTING STRENGTH OF PILLARS

Abstract

The deposit Satkinskoye (the mine Magnesite of PSJC Kombinat Magnezit) has been developed by chamber-and-pillar mining system with ascending and horizontal layers 5 m high and roof supporting with the rib (columnar) pillars by filling the worked
out space with the dry backfill from tailings or crushed waste of the open-pit mine, which provided the extraction of the overlying layer. When using the dry backfill, a question arises about its effect on the supporting strength of the pillars.
Therefore, we have estimated the strength and deformation properties of the dry backfill and studiedn the influence of the backfill on the supporting strength of the pillars. During mining the deposit, it was revealed that the presence of inclined tectonic disturbances, which often develop glide planes, has a significant impact on the stability of the inter-chamber (both columnar and rib) pillars.