Networking reinforcement method for cross drilling holes of outburst coal seam

Abstract

A networking reinforcement method for cross drilling holes of an outburst coal seam is particularly suitable for the cross drilling holes of pre-drainage coal roadway band gas in the outburst coal seam. The method comprises the following steps: about 30-60 days before the excavating of a coal roadway, stopping gas extraction from the cross drilling holes, extending outwards the distance of H2, on two sides of the pre-excavating coal roadway; injecting reinforcement material into the cross drilling holes through an injection pump, wherein the spacing distance of the cross drilling holes is H1 and the cross drilling holes are no longer subject to gas extraction; and filling the slurry into the drilling holes and allowing the slurry to penetrate into the around coal, wherein when the reinforcement material in the holes are solidified, a weak-strong-weak structure system is formed on two sides of the coal roadway, so that the strength and stress distribution of the outburst coal seam is improved, and risks during extraction process can be effectively eliminated. According to the invention, the networking reinforcement method can reduce the deformation of the two sides of the outburst coal seam by 45-65 percent, the reinforcement workload by 35-50 percent, and improves the advance speed of the coal roadway by 40-60 percent, and therefore, has a very good promotional value.

Description

technical field [0001] The invention relates to a network reinforcement method of through-bed drilling holes in high-outburst coal seams, and is especially suitable for reinforcement of through-bed drilling holes with strip gas in pre-extraction coal roadways in high outburst coal seams. Background technique [0002] In my country's coal mining industry, with the increase of mining depth, in-situ stress and gas pressure increase, gas disasters in high outburst coal seams are becoming more and more serious, and regional gas control methods for pre-pumping coal seam gas have become more and more widespread. Applications. At present, domestic coal mining enterprises often use hydraulic punching, hydraulic slotting and other pressure relief and permeability enhancement measures to improve the effect of gas pre-extraction in coal seam strips of coal roadways, thereby eliminating the outstanding danger in the coal roadway excavation area. However, the high outburst coal seam has t...

AI Technical Summary

Problems solved by technology

However, the high-outburst coal seam has the characteristics of low strength and easy breakage. A large number of drilling holes for pre-pumping coal seam gas further reduces the strength of the coal body, resulting in uneven stress distribution inside the coal seam. The frequent occurrence of dynamic phenomena such as sidewalls makes it difficult to support coal seam roadways, which seriously restricts the safe and efficient mining of high outburst coal seams

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