Study on Forced Roof Caving Technology with Super Depth Borehole Blasting Applied to Fully Mechanized Coal Mining Face

In order to solve the storm injured personnel accidents caused by the thick,hard and difficult caving roof of the fully mechanized coal mining face,a theor etical analysis and a site measuring method were applied to study the forced roof caving technology with the super depth borehole blasting for the fully mechanized coa | mining face.With the study on the borehole pattern parameters,borehole loading technique and the forced roof caving safety measures,the forced borehole pattern mo de was provided.The PVC tube loading technique and borehole wood wedge sealing technology were applied to realize the rapid loading and borehole sealing of the bl asting borehole.Thus a max length of the blasting borehole could be 50 m,the blasting strength of the roof was improved and the difficult roof caving problem of the har d and thick roof in the fully mechanized coal miming face could be effectively solved.