Optimization Research on Sectional Coal Pillar Width in Tongchuan Mining Area

According to the over width of the sectional coal pillars, low coal mining rate from the coal mining face in Tongchuan Mining Area, the site measurement, the theoretical calculation, experience formula, numerical simulation and other methods were comprehensively applied to the optimization study on the coal pillar width. The theoretical analysis and site measurements showed that under the steel H-beam ladder shield support condition, the sectional coal pillar width near the one side pl astic zone of the gateway was ranging from 45 m, the coal pillar width near one side plastic zone of goaf was 5.2 m.The coal pillar width in the plastic zone should be C onsidered as 2.54.6 m.According to the mining depth of the mining area, the discrete element numerical software was applied to verify the different width effect of the C oal pillar.Under the steel H-beam shield support conditions, the rational width of the sectional coal pillar was determined as 20 m.