Roof Control Technology by Coal Mining Without Pillars and Gob-side Entry Retaining Pre-splitting Blasting Under Condition of Direct Hard-and-thick Roof

Aimed at the problems of coal mining without pillars technology and god-side entry retaining under the condition of direct hard-and-thick roof, we use deep hole pre-splitting blasting technology to carry out mechanism, methods and mating support technology study of roof control, and successfully conduct on-site experiments; the roof control problems for coal mining without pillars under the condition of direct hard-and-thick roof are successfully solved. The researching results provide the guarantee for mine safety mining and gas control.