Stress Distribution on Blasting Gallery Barrier Pillar due to Goaf Formation During Extraction

Abstract

Semi-mechanised blasting gallery mining is a sustainable option to achieve higher production and productivity from underground thick coal seams. Judicious design of underground blasting gallery panel requires understanding of stress distribution on barrier pillars during different stages of extraction. This paper presents a study of stress distribution in and around barrier pillar for the different stages of extraction in the blasting gallery panel. Finite difference analysis taken up for final excavation (depillaring) in the panel with different stages of extraction. Analysis revealed that the stress transferred on barrier pillar increased as progress of excavation increased. Maximum stress was observed at a distance of 10 and 12 m from the pillar edge for virgin and goaved out panel sideby respectively, which gradually decreased towards centre of the pillar. 2015, The Institution of Engineers (India).