Hard rock roof rock burst segmentation direction control fracturing treatment technology

Abstract

The invention discloses a hard rock roof rock burst segmentation direction control fracturing treatment technology. The technology comprises the following steps of S10, obtaining hard rock roof groundstress parameters; S20, designing an arranging manner of a directional long drill hole and parameters of a direction control fracturing technology; S30, constructing the directional long drill hole;S40, arranging a segmentation direction control fracturing device in the directional long drill hole; S50, carrying out segmentation direction control fracturing construction; S51, forming a manual precast direction control jet crack; S52, forming a fracturing crack net; S53, stopping a pump, draining water, shrinking a packer, and dragging to the next segment of fracturing position; and S54, repeating the steps of S51-53, and finishing whole directional long drill hole fracturing construction. According to the hard rock roof rock burst segmentation direction control fracturing treatment technology, a hard rock roof layer can be precisely controlled, fracturing is carried out segment by segment, a three-dimensional gap communication network is formed, a hard rock roof can be effectively weakened, and the hard rock roof can be promoted to properly collapse.

Description

technical field [0001] The invention belongs to the technical field of underground safety in coal mines, in particular to the technical field of rock burst disaster control technology caused by hard roofs of coal seams, and specifically relates to a segmental and direction-controlled fracturing treatment technology for rock bursts on hard roofs. Background technique [0002] According to statistics, nearly 1 / 3 of the coal seams in China have hard roofs and are widely distributed. The hard roof above the coal seam is mainly a rock formation with stable thickness, high strength, good integrity, and hard to collapse. Its stable mechanical properties and support structure of the working face lead to a large area of ​​roof overhang. With the continuous advancement of the working face, when the roof is difficult to support, the suspended roof suddenly collapses, causing a large area of ​​pressure in the stope, and under the action of the large caving step of the thick and hard roc...

AI Technical Summary

Problems solved by technology

However, in the treatment of hard roofs by existing hydraulic fracturing technology, artificial prefabrication is difficult to control the direction of injection fractures, the scale of fracture development is limited, and the weakening effect is difficult to guarantee

Moreover, during the conventional drilling construction process, the drilling precision is low, and it is easy to deviate from the treatment target layer, resulting in poor fracturing weakening effect, and it is difficult to eliminate or reduce the strong mine pressure problem caused by the hard roof; when the drilling precision is low and the fracturing Weakening the roof strata in non-target layers can easily cause roof caving or leaking, which restricts mine safety production

Conventional fracturing treatment of hard roof technology has a large overall construction volume, small effective pressure relief area, blind spots and blind sections, it is difficult to form a three-dimensional effective fracture network system, and cannot fully release hard rock formations and recovery dynamic pressure energy to achieve full pressure relief put the top

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