Research of Large-Area Hard Roof Caving Prevention and Control System in Shortwall Mining Face

Abstract

In the mining process, if the roof is very hard, it will hang in a large area in the gob. The hanging roof may cave suddenly, which will crash the mining face and generate hurricanes so as to cause casualties and equipment damage. The hard roof control technology has mainly been used in the longwall mining face in coal mines for a long time, and made little use in shortwall mining face. The factors of roof caving is analyzed in shortwall mining area, which mainly consists of the coal pillar size and layout, the length of coal face, roof thickness and strength, the overburden load, the supporting conditions of roof and so on and the relationship of the factor and the limit caving area is studied. And then a new integrated control technology system is put forward, which includes: support and isolation by coal pillars, roof caving pressure relief, monitoring and early warning of roof fall, gob sealing by the stopping walls, and the principle of different technology and the parameter selection method is claimed. This technology is applied in Shangwan Mine of Shendong Group in China and the results shows that the hard roof caves naturally in small area, the hidden danger of large-area roof caving is eliminated completely, so the coal production is guaranteed to be safe.