Industrial test method for pre-cracking and anti-reflection of high gas coal roadway

Abstract

The invention discloses an industrial test method for pre-cracking and anti-reflection of a high gas coal roadway. The industrial test method comprises the following steps that monitoring devices forrealizing surface displacement monitoring of the roadway, roof separation monitoring of a back, deep multi-point displacement monitoring of roadway surrounding rocks and stress monitoring of a bolt and / or a cable is arranged are set positions; fracturing holes are formed in a heading face, gas drilling fields are arranged on two sides of the heading face, pre-extraction holes are formed in the drilling fields, the fracturing holes are subjected to CO2 pre-cracking, and gas is extracted from the pre-extraction holes; small guide pipe advanced grouting is performed in a driving working face; andthe gas extraction effect analysis before and after the fracturing and the permanent support effect analysis of the driving working face are performed, monitoring data acquired by the monitoring devices is combined, and the rationality of the relevant design parameters is judged.

Description

technical field [0001] The present disclosure generally relates to the technical field of coal roadway mining, and in particular to an industrial test method for pre-splitting and anti-permeability of high-gas coal roadway. Background technique [0002] At present, many coal mines in my country are high-gas mines. With the continuous increase of the total demand for coal, the mining has continued to advance to the deep, and the gas content in deep coal seams has increased significantly. For deep low-permeability and high-gas coal seams, conventional gas drainage methods, such as pre-drainage and local coal seam drainage, are difficult to effectively release a large amount of gas from the coal seam, resulting in extremely high gas pressure in the coal seam. The main problems are: the effective impact range of drilling is small, the construction workload is heavy, and the drainage efficiency is low. It is necessary to take effective technical measures such as pressure relief a...

AI Technical Summary

Problems solved by technology

For deep low-permeability and high-gas coal seams, conventional gas drainage methods, such as pre-drainage and local coal seam drainage, are difficult to effectively release a large amount of gas from the coal seam, resulting in extremely high gas pressure in the coal seam

The main problems are: the effective impact range of drilling is small, the construction workload is heavy, and the drainage efficiency is low. It is necessary to take effective technical measures such as pressure relief and anti-reflection, expanding the effective impact range of drilling, and improving the sealing effect of drilling to achieve improved Purpose of Gas Drainage Efficiency

However, if the pre-cracking is excessive, it is very easy to cause a roof fall accident on the excavation face.

In the existing technology, there is no good method to ensure that the relevant design in actual construction can effectively control the range of pre-cracking

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