A method for preventing and controlling rockburst in near-vertical coal seams by deep and shallow hole depressurization blasting

Abstract

The invention provides a method for preventing rock burst of a nearly-upright coal seam by deep and shallow hole relaxation blasting, and belongs to the technical field of prevention of rock burst disasters. The method comprises the steps that firstly, a stress concentration zone is determined according to monitoring data; then, multiple rows of deep blasting holes and shallow blasting holes are alternately formed in top and bottom plates of the area to be subjected to pressure relief, two deep blasting holes are formed in each row, three shallow blasting holes are formed in each row, the rowspacing is 20m, the direction of the blasting holes is distributed in the shape of a fan, and the depth of the blasting holes can at least reach a peak value area of the bearing pressure; after drilling is completed, charging is carried out, a leading wire is connected, hole sealing is carried out, positive manual charging is adopted, loess is used for blocking, and the wire connection method adopts parallel connection in the holes and series connection between the holes; and finally, blasting is performed by a blasting machine, the blasting method adopts a single-time single-row mode, the advanced blasting distance of the deep blasting holes is controlled between 30m and 90m, and the shallow blasting holes follow the working face for promoting blasting. The method for preventing the rockburst of the nearly-upright coal seam by deep and shallow hole relaxation blasting can significantly reduce the stress concentration of the working face, can weaken the risk of the rock burst of the working face, and is suitable for steeply-inclined and nearly-upright coal seams.

Description

technical field [0001] The invention relates to the technical field of rock burst disaster prevention and control, in particular to a method for preventing and controlling rock burst in a near-vertical coal seam by deep and shallow hole pressure relief blasting. Background technique [0002] Rockburst is a typical coal-rock dynamic disaster, which is extremely destructive, often causing damage to wells and roadways, casualties, and serious secondary disasters such as gas and coal dust explosions. With the increase of coal mine mining depth and the increasingly complex mining layout, the stress environment of the surrounding rock is gradually deteriorating, and the situation of rock burst disasters is becoming more and more serious, and the occurrence is becoming more and more frequent. The research on the prevention and control of rock burst has become a hot topic in the coal mining industry. [0003] Roof and floor are one of the main factors affecting the occurrence of ro...

AI Technical Summary

Problems solved by technology

However, for the pressure relief blasting of near-vertical coal seams at present, due to the particularity of coal seam occurrence, the traditional blast hole arrangement is often difficult to achieve the expected pressure relief effect, and it is very likely to cause abnormal stress transfer and induce impact disasters

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