Gob-side entry narrow coal pillar advanced grouting reinforcement method

Abstract

The invention provides a gob-side entry narrow coal pillar advanced grouting reinforcement method. The method comprises the steps that before extraction of a gob-side entry upper section working face,a row of drill holes are formed in one side of an excavated upper section entry in the extending direction of a coal pillar; the drill holes are detected through a drill hole penetrometer; accordingto obtained information data of pressure and displacement in the drill holes, the compression degrees of the coal pillar at different depths and the development condition of cracks in a coal body areanalyzed, grouting reinforcement operation can be directly conducted on the part, with the large crack development, in the coal pillar, and fracturing operation is conducted on the part, with the small crack development, in the coal pillar; fracturing operation is conducted on the part, with the small crack development, in the coal pillar through an electric pulse device; the impact wave fracturing range is observed till fracturing of all the areas, with the small coal pillar cracks, in the whole upper section entry is finished; and on the basis of original anchor net supporting of the coal pillar, grouting anchor rods are placed in the drill holes to conduct grouting reinforcement on the interior of the coal pillar. According to the method, advanced reinforcement operation of the coal pillar can be effectively achieved.

Description

technical field

[0001] The invention belongs to the technical field of surrounding rock control of gob-side roadways in coal mines, and in particular relates to an advanced grouting reinforcement method for narrow coal pillars in gob-side roadways. Background technique

[0002] At present, my country's coal mining is mainly in the underground mining mode, and the instability of the roadway surrounding rock is one of the main problems in deep mine mining. During the underground mining process, the surrounding rock deformation and instability of the roadway due to the impact of mining and roof pressure have seriously affected the safe and efficient production of coal mines. In the gob-side roadway, the deformation and instability of the narrow coal pillar on one side of the mining face is a common problem. In order to effectively solve this problem, it is usually reinforced by grouting after the coal pillar is damaged. This method is lagging Grouting, often because the timing...

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