Judgment method for the distribution of surface through-cracks and air leakage characteristics in shallow buried coal seam mining

Abstract

A method for determining earth surface interpenetrated crack distribution and air leakage characteristics in shallow burial coal mining. The method comprises the following steps: determining the similar experimental material ratio according to actual stratum data of a mine; laying a similar material model according to the geometric similarity and the power similarity; conducting coal bed excavation after the material strength and the raw rock strength are similar, and taking fracture development pictures after the model excavation is stable; conducting graying and vectorizing on the pictures by means of image processing software; importing the vectorized fracture images to numerical simulation software, and conducting calculation; and comparing the obtained result with measured data, and obtaining an accurate numerical model by means of continuous modification. By means of the method, the overlaying strata fracture distribution and air leakage characteristics under the shallow burial coal bed condition can be disclosed, and the beneficial reference is provided for the on-site situations such as the blockage of air leakage passageways.

Description

technical field [0001] The invention relates to a method for judging the distribution of surface through-cracks and air leakage characteristics in shallow buried coal seam mining, which belongs to the experimental research on fissure rock mass in the field of underground geotechnical engineering and the research on the judging method for air leakage characteristics of surface fissures. Background technique [0002] my country's coal mining strategy has moved westward, and most of the western mining areas are shallow buried coal seams. The surface air leakage of shallow buried coal seam mining is serious, and it is easy to cause spontaneous combustion of coal in goafs. Coal spontaneous combustion will not only affect the normal production of mines, but also may cause serious fire or gas explosion accidents. Due to the shallow burial of coal seams in the west, a large number of fissures penetrating the surface are formed under the action of mining stress, and these fissures co...

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Problems solved by technology

[0004] Purpose of the invention: Aiming at the deficiencies of existing numerical simulation methods, the present invention introduces the development of cracks into the numerical model by combining similar material simulation experiments with numerical simulations, and overcomes the difficulty of crack detection in rock bodies and excessive numerical models. At the same time, the correction of the model can effectively improve the accuracy and reliability of the model, and provide a useful reference for the distribution of surface penetration cracks and the characteristics of air leakage after mining in shallow buried mining areas.

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