A water-separation method for grouting reinforced water-rich gravel layer on the roof of coal mining face

Abstract

The invention discloses a grouting reinforcement waterproof method for a water-rich gravel layer of a coal face roof. The method comprises the steps that line-shaped grouting drill holes are formed inthe ground, and the distance between the drill holes is 30 m; each drill hole is divided into an upper section and a lower section, and full-hole rock-core-free drilling is achieved; a sleeve is installed in the upper section of each drill hole, the lower section is a grouting pipe, and the final hole is deepened into the coal seam roof bed rock; grouting is conducted in a jumping hole interval and descending advancing type grouting mode, intermittent hole penetrating is conducted, and pouring is conducted for multiple times; and after the pressure of the grouting final hole reaches the grouting ending standard, hole sealing is conducted, and grouting is ended. The technical scheme is safe and reliable, the technical achievement universality is high, and the gravel aquifer is transformedinto a water-resisting layer or a weak aquifer.

Description

technical field [0001] The invention relates to the technical field of grouting construction of a water-rich gravel layer on the roof of a coal mining working face, in particular to a method for grouting reinforcement of a water-rich gravel layer on the roof of a coal mining working face. Background technique [0002] The bedrock of the coal seam roof in some mining areas of the North China type coalfield is relatively thin, and the bedrock is composed of sand, gravel, sand pebble, semi-consolidated glutenite and marl, overlying Quaternary and Neogene thick unconsolidated pore water. Because the bedrock (thickness: 4-40m, average 9m) of the wellfield is weathered to varying degrees, with developed fissures and poor water-repellent performance, the existence of the roof caving fissure zone after mining in the working face will completely lose the water-repellent effect. If reasonable and effective maintenance measures are not taken, not only the recovery efficiency will be re...

AI Technical Summary

Problems solved by technology

However, due to the great difference in the composition of the rocks that make up the formation, the roof aquifer generally has a wide distribution range, and the water state changes greatly. The method of roof grouting is high in cost and poor in effect.

Scholars at home and abroad have little research on the grouting reinforcement of the aquifer on the roof of the working face. The current grouting reinforcement methods often fail to meet the expected requirements and progress goals during construction. Generally, the drilling holes are shallow and densely packed. Only 1-2m, the construction process is cumbersome

Grouting the water-rich gravel layer on the roof of the coal mining face to reinforce the water barrier and maintain the integrity of the roof. At present, there is no mature technology in China

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