A two-way reinforcement method for coal pillars in gob-side roadway

Abstract

The invention provides a gob-side entry driving coal pillar bi-directional reinforcing method, which comprises the following steps of newly digging a roadway at one side close to a goaf, reserving a coal pillar between the goaf and the newly dug roadway, newly digging a side drill hole in the coal pillar, and placing an expansion locking type two-ended cable which penetrates through the reserved coal pillar; injecting slurry into the front end of the expansion locking type two-ended cable, expanding and solidifying the slurry in the goaf to form a stable anchoring body, applying a prestressing force on the expansion locking type two-ended cable at one side of the newly dug roadway and anchoring, and realizing bi-directional reinforcing of the reserved coal pillar; sequentially constructing the expansion locking type two-ended cables along a roadway driving direction, so that the reserved coal pillars of a whole working surface are penetrated and reinforced. According to the gob-side entry driving coal pillar bi-directional reinforcing method provided by the invention, the difficult problem that a traditional gob-side entry driving technology cannot realize one-way construction and bi-directional reinforcement is broken through, the problem that the preserved coal pillars are instable when two sides of a rock body are constructed at the same time is also solved, the bearing force of the coal pillars to a top plate is improved, the bearing force and the stability of the roadway-protection coal pillars are improved, and the method has a wide practical value.

Description

technical field [0001] The invention relates to the technical field of coal mining, in particular to a bidirectional reinforcement method for coal pillars in gob-side roadway. Background technique [0002] As the coal mine enters deep mining, the stress of the original rock increases, and the width of the coal pillars in the roadway becomes larger and larger, resulting in a large amount of waste of coal resources. Starting from the perspective, the coal pillar-free roadway mining technology including gob-side retaining and gob-side driving has been carried out. Gob-side driving technology is widely used because it can effectively avoid the stress disturbance on the coal pillar caused by mining at the upper working face, and the maintenance of the roadway is relatively simple and the maintenance cost is low. Since gob-side entry relies on narrow coal pillars to support the roof of the roadway, it is necessary to strengthen the support for narrow coal pillars. The existing c...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to solve the problems existing in the prior art, and to design a method for two-way reinforcement of coal pillars in gob-side excavation, which can quickly and effectively complete the two-way reinforcement of coal pillars on one side of the newly excavated roadway, and realize coal pillar reinforcement. Reinforcement of lateral confining pressure, thereby improving the bearing capacity of coal pillars, and also breaking through the problem that traditional gob-side entry technology cannot realize two-way reinforcement in one-way construction

Images