Similar Material Simulation Study on Isolated Coal Pillar Gangue-paste Backfill Mining

Based on similarity principle and similar material simulation test, the abutment pressure distribution laws during isolated coal pillar gangue-paste backfill mining and relationship between stope and surrounding rock were studied. The results showed that gangue-paste backfill mining only changed the magnitude of stress instead of stress state ahead work face; with the working face advanced, a "pillar-backfill-wall" supporting structure was formed in stope to support the roof; the backfill body provided lateral constraint, which could improve the stability of coal pillar and decrease the width of pillar, and improve the recovery rate of coal resource.