Method for determining height of overlying stratum water guiding crack zone

Abstract

The invention discloses a method for determining the height of an overlying stratum water guiding crack zone. The method includes the steps of 1, according to the thickness, the volume weight, the elastic modulus and the tensile strength of strata overlain on a coal mining working face, judging whether a primary key stratum and/or a secondary key stratum exist/exists in the strata overlain on the coal mining working face or not, and determining the positions/position of the primary key stratum and/or the secondary key stratum; 2, primarily judging the position of the primary key stratum in three overlying stratum zones according to the ratio of rock and loading and the ratio of rock and mining, and primarily determining the range of the height of the overlying stratum water guiding crack zone; 3, calculating the total tensile deformation of the strata overlain on the coal mining working face under three conditions, comparing the total tensile deformation of the strata overlain on the coal mining working face with the ultimate tensile deformation of the strata overlain on the coal mining working face, and judging whether the strata overlain on the coal mining working face are broken or not; 4, determining the height of the overlying stratum water guiding crack zone under three conditions. The steps of the method are simple, the method for determining the height of the overlying stratum water guiding crack zone is simplified, and the accurate result can be obtained.

Description

technical field [0001] The invention belongs to the technical field of coal seam mining, and in particular relates to a method for determining the height of a water-conducting fracture zone in overlying rock. Background technique [0002] As an important part of the concept and technical system of coal green mining, water conservation mining has attracted increasing attention from scientific and technological workers and public opinion in recent years. As the country attaches great importance to water conservation coal mining in ecologically fragile areas, the "National Energy Development "Twelfth Five-Year Plan" (Guofa [2013] No. 2) issued by the State Council on January 1, 2013 has included "water conservation mining technology" Listed as one of the new technologies actively promoted. Water-preserving mining is to make the water-conducting cracks in the overlying rocks caused by mining impermeable to the surface or water-bearing rock formations, so as to protect water res...

AI Technical Summary

Problems solved by technology

Although this method considers various main factors affecting the height of the water-conducting fracture zone, it only assigns a certain weight to each influencing factor subjectively and qualitatively, and there is no discussion on the calculation formula under different geological and mining conditions. Instead, a unified Substituting a few simple parameters into the calculation formula has certain blindness and limitations, and the calculation results often have large errors

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