A similar simulation method for grouting filling in the caving area of ​​broken roof

Abstract

The invention discloses a cracked roof caving region grouting filling similar simulation method. The method includes the steps that a geometric similarity ratio of a similar simulation experimental model is determined; a coal bed bottom plate and a coal bed are laid according to the geometric similarity ratio and a laying scheme; the side length a and the number n of layers of cubes of an immediate roof are determined, and then laying of the immediate roof is conducted; similar simulation materials are laid above rock stratums of the cubes, and a grouting filling roadway and grouting drilling holes are reserved in corresponding positions; steps of open-off cut and working face simulation support installing are conducted. Due to the fact that the regular cubes are utilized to simulate the immediate roof, the requirements of a cracked roof caving region grouting filling similar simulation experiment for simultaneously conducting mining and caving of a cracked roof can be met; breakage expansion coefficients of a cracked roof after caving can be controlled by adjusting the side length of the cubes and the free caving height of the cracked roof, it can be guaranteed that the cracked roof caving region grouting filling similar simulation experiment can well simulate the field, and the problems that in the prior art, similar materials are utilized to simulate the caving process of the caving region, simulation is inaccurate, and the simulation result does not conform to the actual situation are solved.

Description

technical field [0001] The invention belongs to the technical field of mining, and in particular relates to a similar simulation method for grouting and filling in the caving area of ​​a broken roof. Background technique [0002] Grouting filling in the caving area of ​​the broken roof is to inject grout into the rock void before the caving rock is compacted, so that the grout occupies the caving rock void, thereby reducing the movement space of the overlying rock layer, achieving control of the overlying rock layer movement, slowing down The purpose of ground subsidence, however, since the grouting filling area of ​​the caving area is behind the working face, it is a concealed project. For the flow law of the filling slurry in the caving gangue gap, the caving gangue and the caving gangue grouting filling body pressure The actual process cannot be observed, so a similar simulation method for grouting filling in the caving area of ​​the broken roof that can intuitively refle...

AI Technical Summary

Problems solved by technology

[0002] Grouting filling in the caving area of ​​the broken roof is to inject grout into the rock void before the caving rock is compacted, so that the grout occupies the caving rock void, thereby reducing the movement space of the overlying rock layer, achieving control of the overlying rock layer movement, slowing down The purpose of ground subsidence, however, since the grouting filling area of ​​the caving area is behind the working face, it is a concealed project. For the flow law of the filling slurry in the caving gangue gap, the caving gangue and the caving gangue grouting filling body pressure The actual process cannot be observed, so a similar simulation method for grouting filling in the broken roof caving area that can intuitively reflect the above process is needed, and this method can be used in scientific research and teaching

[0003] In simulating the grouting filling in the caving area of ​​the broken roof, the key is to make the coefficient of expansion of the direct roof the same or similar to that of the field, and it should conform to the characteristics of the broken roof as it is mined and cascaded; It is river sand, calcium carbonate and gypsum, and its crushing property after caving is far from that of real rock, and its crushing coefficient after caving is random and uncontrollable; it cannot simulate the broken roof well The characteristics of picking and taking

To sum up, the current simulation method cannot meet the requirements of the similar simulation test of grouting filling in the caving area of ​​the broken roof for the direct roof to follow the mining and caving and maintain a certain broken expansion coefficient after caving.

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