Sub-level caving mining with seam of thickness dirt band

The paper introduces the attempts to subject seam of thickness dirt band to fully-mechanized with sub-level caving in Kailuan Fangezhuang mine depending on site practical data and combining experimentation with theoretical study. By analogue simulating test, the paper discusses fully-mechanized sub-level with dirt band, the top-coal caving and drawing property, the caving procedure and drawing law, and the dirt band critical thickness related to complex structure thickness seam of 2429S. The paper features the rule governing the movement of top-coal with dirt band and the technical measures of sub-level caving mining.