Design method of narrow coal pillar width in gob-side entry retention

Abstract

The invention discloses a gob-side entry retaining narrow coal pillar width design method. The method includes presetting narrow coal pillar width w to obtain coal pillar strength S1 on the basis; calculating coal pillar stress S2 according to specific geological conditions of the narrow coal pillar; investigating whether the narrow coal pillar safety factor SF satisfies the tunneling requirements, wherein the narrow coal pillar safety factor SF= coal pillar strength S1 / coal pillar stress S2, when SF is equal to or more than 1.0, the designed narrow coal pillar width meets the tunneling requirements; when SF is less than 1.0, the designed narrow coal pillar width does not meet the requirements, and the preset value needs to be revised. The design method is simple and clear, can be used asearly-stage design reference and can also be used for the design of the construction process.

Description

technical field [0001] The invention relates to a method for designing the width of narrow coal pillars in gob-side entry retention. Background technique [0002] Beginning in the 1950s, goaf entry began to be used in many mining bureaus in my country. At first, gob entry was retained in a complete sense, and various materials such as wooden pillars, gangue bags, concrete blocks, and metal pillars were used on the edge of the gob. Support roadway. At present, there are few tunneling along the goaf in the strict sense, and they are basically the edge of the goaf, and a certain width of the narrow coal pillar is reserved for tunneling. [0003] The narrow coal pillar has two main functions, first, to support the load of the overlying strata, and second, to prevent air leakage and water leakage in the adjacent goaf. For the fully mechanized caving face, gob-side digging is very beneficial for roadway maintenance. For fully mechanized caving working faces in thick coal seams, ...

AI Technical Summary

Problems solved by technology

In the appeal research method, less attention is paid to the physical and mechanical parameters of the coal pillar itself, and the key parameters such as the physical and mechanical parameters of the coal pillar itself in the design formula

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