Opposite pulling type anchor rods for gob-side entrydriving small coal pillar and support method thereof

Abstract

The invention discloses opposite pulling type anchor rods for a gob-side entrydriving small coal pillar and a support method thereof. A middle pull rod body of each opposite pulling type anchor rod is sleeved with two rubber pulp stopping valves in a spaced mode, and one of the rubber pulp stopping valves is provided with a pulp pouring hole; large deformation devices with the same structure, trays and nuts are symmetrically connected to the two ends of each middle pull rod body, and the trays and the nuts are matched with one another; each large deformation device comprises a sleeve, a high-strength compression spring, a fastening bolt and a connection piece, wherein one end of the sleeve is a seal bottom with a through hole, and the other end of the sleeve is an opening end; each opening end is in threaded connected with the corresponding connection piece, and each connection piece is in threaded connection with the corresponding middle pull rod body; and each high-strength compression spring is installed in the corresponding sleeve, and after each fastening bolt penetrates through the corresponding high-strength compression spring, the threaded head of the fastening bolt is exposed out of the corresponding sleeve seal bottom through hole. When the opposite pulling type anchor rods are used for supporting the small coal pillar, a support mode that the pulp is poured in the middle, and the two ends are pre-tightened is formed, large deformation of the coal pillar is adapted, and meanwhile the safety and stability of the coal pillar are ensured.

Description

technical field [0001] The invention relates to the support technology of coal mine recovery roadway, in particular to the support technology of small coal pillars along goaf roadway. Background technique [0002] In the process of coal mining, gob-side entry has good technical advantages and economic benefits. It not only effectively alleviates the tension of mine working face replacement, but also significantly improves the recovery rate of coal resources. It is of great significance to the realization of safe and efficient modern mining in coal mines. However, due to the structural evolution of the overlying strata and the strong disturbance of mining, small coal pillars in gob-side excavation are severely damaged, deformed, and poor in stability. As the service time of the roadway increases, the bearing capacity of the coal body gradually decreases. The support problems include: The lateral deformation of small coal pillars is large, and slabs occur from time to time; ②T...

AI Technical Summary

Problems solved by technology

However, these support methods do not take into account the large deformation characteristics of small coal pillars in gob-side excavation, which makes the support system and coal pillar deformation inconsistent, resulting in failure of the support structure and the final overall failure of the coal pillar. Improvement and development are urgently needed for the support device and method of small coal pillars in roadway

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