A Two-lane Deformation Control Method of Reserved Pressure Relief Observation Borehole and Combined Grouting

Abstract

The invention discloses a two-roadway deformation control method with reserved pressure relief observation drilling holes for combined grouting. The two-roadway deformation control method with the reserved pressure relief observation drilling holes for combined grouting is applicable to compact impact inclined coal seams in coal mining engineering. The two-roadway deformation control method with the reserved pressure relief observation drilling holes for combined grouting comprises the steps that upward grouting drilling holes, downward grouting drilling holes, upward pressure relief observation drilling holes and downward pressure relief observation drilling holes are formed in the coal sides of two roadways at intervals, wherein the upward grouting drilling holes and the upward pressurerelief observation drilling holes are in one group, the downward grouting drilling holes and the adjacent downward pressure relief observation drilling holes are in one group, and grouting anchor cables are installed in the grouting drilling holes; fluorescent coatings are sprayed on the inner walls of the pressure relief observation drilling holes, and a reasonable grouting timing is determined by observing the collapse of the inner walls of the pressure relief observation drilling holes and the stripping degree of the fluorescent coatings; when the inner walls of the pressure relief observation drilling holes are relatively stable and compact, a grouting process of the adjacent grouting drilling holes is not started; when section collapsed coal dust of the inner walls of the pressure relief observation drilling holes exceeds 1 / 3 of the section area, the grouting process is started; and in addition, the pressure relief observation drilling holes can further be used as pressure reliefdrilling holes to relieve the impact tendency of the coal seams and the influence range of advance support pressure.

Description

technical field [0001] The invention relates to a two-lane deformation control method of reserved pressure relief observation boreholes combined with grouting, especially a reserved pressure relief observation borehole combined with joint grouting suitable for coal mining engineering under the condition of dense impact-inclined coal seams. Two-lane deformation control method for pulp. Background technique [0002] The sudden collapse or fall of coal and rock mass with a large amount of elastic energy under high stress state, accompanied by dynamic effects such as sound, vibration or air wave, is collectively referred to as coal mine dynamic pressure phenomenon. In recent years, the occurrence probability of coal mine dynamic pressure phenomenon generally increases with the increase of mining depth, but coal mine dynamic pressure phenomenon may also occur in shallow coal seams with complex mining conditions. Generally speaking, coal seams with impact tendency widely exist in...

AI Technical Summary

Problems solved by technology

The effect of grouting is difficult to meet expectations

[0005] 2) There are many blind areas in the grouting diffusion range, and it is difficult to evaluate the grouting effect

In tight coal seams, the amount of grouting is often different in different boreholes, causing many confusions and difficulties

[0006] 3) It is difficult to grout in tight coal seams, and the grout is concentrated in a certain section of the borehole relying on gravity

These phenomena all prove that the current grouting effect in tight coal seams is not ideal, and the actual effect cannot be achieved.

Images