A method for ground grouting to reinforce a broken roof

Abstract

The invention discloses a method for ground grouting to reinforce a broken roof, comprising the following steps: S1, selecting grout; S2, calculating the porosity of the goaf; S3, constructing a grouting model, and determining the height of grouting reinforcement; S4, grouting holes Layout; S5, drilling and grouting. The present invention can calculate the porosity and construct the grouting model according to the actual situation of the goaf, can reasonably determine the drilling position and the grouting reinforcement height, effectively improves the grouting effect, and greatly improves the overall strength of the broken roof of the coal seam. It also reduces a certain amount of work, and has a significant progressive effect on the reinforcement of the broken roof of extra-thick and relatively thick coal seams.

Description

technical field [0001] The invention relates to the field of coal mining grouting, in particular to a method for ground grouting to reinforce a broken roof. Background technique [0002] Coal is an important basic energy and raw material. The sustainable and healthy development of the coal industry has made a significant contribution to the development of the national economy. Reasonable design and scientific coal mining are the inevitable trend to achieve safe and efficient production in coal mines. However, various safety accidents in coal mines occur frequently, among which roof accidents have the highest incidence rate, which is 2.23 times that of transportation accidents and 3.49 times that of gas accidents. major part of the accident. In order to control the occurrence of coal mining roof accidents under the direct cover of the caving zone, mining engineers began to practice using underground bedding drilling pre-grouting to strengthen the roof, and the grouting mater...

AI Technical Summary

Problems solved by technology

However, under the condition of no pressure, the free diffusion of cement grout is not uniform, and the grout solidifies rapidly, which makes it impossible to cover a large area. It is also seriously affected by the disadvantages of complex on-site operating environment, small diffusion radius, large drilling engineering, and high grouting cost. Working face replacement and safe and efficient recovery

[0003] Bottom hole drilling and grouting are mostly used in the existing technology, but when the working face has a thick fragile roof, the effect of using bottom hole drilling and grouting is average. First, the thickness of the fragile roof is relatively large, and the amount of work is large; secondly , the construction angle limit of underground drilling is relatively large, and the drilling is difficult to meet the design requirements, resulting in poor grouting effect; finally, the grouting range of the underground roof drilling is small, the hole sealing is difficult, the slurry is easy to flow out, and the grouting effect is poor

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