Method and system for judging groutability of overlying strata separation layer

Abstract

A method for evaluating groutability of overlying strata separation comprises the following steps that S1, two drill holes are formed in a grouting target area, one drill hole serves as a grouting hole, and the other drill hole serves as an observation hole; s2, grouting is conducted in the grouting hole, the grouting pressure of the grouting hole and whether slurry returns to the observation hole or not are monitored, if the grouting pressure change curve is in an M shape, the overlying strata separation layer has groutability, and if slurry returns to the observation hole, the grouting hole communicates with the observation hole; and S3, grouting is conducted on the grouting hole and the observation hole at the same time, the grouting pressure of the grouting hole and the grouting pressure of the observation hole are monitored, and if the grouting pressure of the grouting hole and the grouting pressure of the observation hole are mutually coupled, the grouting hole and the observation hole have relevance. An overlying strata separation groutability evaluation system comprises two identical pressure monitoring devices, a first pressure gauge monitors the pressure of injected slurry, and a second pressure gauge monitors the static pressure of the liquid level in an air chamber. The practicability of the overlying strata separation layer filling mining technology is improved.

Description

technical field [0001] The invention relates to the field of grouting filling of overlying rock detached layers, in particular to a method and system for evaluating the injectability of overlying rock detached layers. Background technique [0002] Overlying strata detachment layer grouting filling technology is to use the detachment space in the process of overlying rock destruction, inject fly ash slurry and other filling materials into the detachment space through bottom drilling holes, so as to prevent the further occurrence of overlying rock at the grouting layer Destruction, slowing down the propagation speed of overlying rock movement to the upper surface, controlling the movement of rock strata and finally achieving the purpose of reducing surface subsidence. In the application process of the overlying rock separation layer grouting filling technology, determining the injectability of the overlying rock separation layer is the basis of the overlying rock separation la...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the problems of high cost in the method for evaluating the injectability of the overlying rock separation layer, the present invention provides a method for evaluating the injectability of the overlying rock separation layer. Two boreholes are arranged on both sides of the working face, one of which is a grouting hole, The other one is an observation hole, which injects grout into the grouting hole to monitor the change of the grouting pressure (that is, the injection grout pressure and the static pressure of the grouting liquid surface). At the same time, if the phenomenon of slurry return occurs in the observation hole, it indicates that the two boreholes are connected. Aiming at the method for judging the injectability of the overburden separation layer, the present invention provides a system for evaluating the injectability of the overburden separation layer. The first pressure The gauge is used to monitor the variation of the injected grout pressure, and the second pressure gauge is used to monitor the static pressure of the liquid surface in the air bag (11), that is, to monitor the static pressure of the grouting liquid surface. Practicality

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