METHOD FOR OVER-PIT AND UNDER-PIT COOPERATIVE CONTROL OF ROOFS OF FAR AND NEAR FIELDS OF AN EXTRA-LARGE STOPING SPACE

摘要

The invention relates to a control method for a hard roof of a coal mine, specifically to a method for over-pit and under-pit cooperative control of roofs of far and near fields of an extra-large stoping space. The method provided by the invention overcomes the problem of lack of comprehensive and cooperative control methods for hard roofs of far and near fields of an extra-large stoping space in the prior art. According to a technical scheme in the invention, the method comprises an over-pit vertical hole hydraulic fracturing method, an over-pit L-shaped hole hydraulic fracturing method, an over-pit highly-energy-gathered repetition pulse strong shock wave method, an under-pit water injection method, an under-pit layered blasting method and an under-pit hydraulic fracturing method. The method has the advantages that 1) the problem of great mine pressure of the extra-large stoping space is effectively controlled through over-pit and under-pit cooperative control of the hard roofs of far and near fields; 2) advantages of the variety of methods are given to full play and disadvantages of the variety of methods are mutually compensated, so weakening effect on the hard roofs is substantially improved; and 3) all the over-pit and under-pit holes can be used independently or be used in a shared way, so time, manpower, material resources and money used for hole perforation can be greatly reduced.