Roof Giant Conglomerate And Technology Controlling Roof Water

With the increase of the depth of excavating, the giant thick conglomerate aquifer of Tertiary system threatens evidently mining the fourth coal seam, which is in Shanxi group in Huafeng coal mine. Characteristics of geology and hydrologic geology are analyzed on the base of fully knowing the control theory and technology of water-inrush from roof in the world. The distributive characteristic and law of the sandstone and conglomerate is summarized according to the data of drills and mining coal. The distributive law and water-bearing characteristic of the giant thick conglomerate in the deep area is found with applying the geophysical exploration of instant change electromagnetism system. Based on the underground pressure theory, similar material test and computer numerical simulation, the over strata moving characteristic under the condition of the giant thick conglomerate and coal measures strata is studied, and the development characteristic of water flowing fractured zone and streak crack line evolution is revealed. The method calculating water flowing fractured zone is deeply studied. The relationship between water inrush from roof conglomerate aquifer and water flowing fractured zone and streak crack is studied on the base of analysis affecting the water-inrush from roof. The mechanical model of water-inrush from workface lower level alley is established with the example of water-inrush on workface 1409. Technology controlling roof water-inrush from giant conglomerate is discussed.