Internal injection replacement support room type coal pillar recovery method

Abstract

The invention discloses an internal injection replacement support room type coal pillar recovery method. In the process of room type coal pillar recovery, room type coal pillars with an aspect ratio greater than 0.6 are divided into reserved coal pillars and pre-mining coal pillars, after the mining of the pre-mining coal pillars, cement filling materials are injected into goafs surrounded by thereserved coal pillars, after the goafs are stabilized, the coal pillars are replaced with the goafs for supporting, and the reserved coal pillars are recovered; and based on the Winkel beam theory, amechanical model of the reserved coal pillars in the stage of supporting overlying strata is established, and the displacement and force conditions of roofs of the reserved coal pillars in the supportstage are obtained. According to the first strength theory of the roofs and the criterion of the ultimate strength of the reserved coal pillars, the theoretical setting width of the reserved coal pillars is obtained. The internal injection replacement support room type coal pillar recovery method can not only efficiently recover valuable coal resources and reduce waste of the coal resources, butalso can effectively support the overlying strata and prevent a series of mine safety problems.

Description

technical field [0001] The invention belongs to the technical field of coal pillar recovery, and in particular relates to a method for recovering a room-type coal pillar with an internal injection replacement support, and is especially suitable for the recovery of room-type coal pillars with an aspect ratio greater than 0.6 left over from coal mining in coal mines. Background technique [0002] The room-type mining method in my country is mostly used in the northwestern region, mainly in Shaanxi, Inner Mongolia, Shanxi and other mining areas with wide distribution of resources, simple geological structure, and shallow coal seam occurrence. Although the room-type coal pillar has the characteristics of low investment, simple management, and high production efficiency, the coal pillar left after mining will directly affect mine safety and threaten the surrounding ecological environment. Recycling the coal pillars left by room mining can simultaneously solve the problems of wast...

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Problems solved by technology

[0003] At present, domestic room-type coal pillar recovery methods are mainly divided into traditional recovery methods and filling recovery methods. Among them, traditional recovery methods such as column splitting and warehouse wing recovery have low recovery rate and low degree of mechanization, and filling recovery methods such as throwing Filling and recycling and comprehensive mechanized filling and recycling require a lot of filling material costs and equipment investment costs

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