Patent · US Active

Internally injected replacement support room-type coal pillar recovery method

US11313226B2 · kind B2 · utility

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5Claims
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Assignee

Inventors

Key dates

Filing dateFeb 22, 2019
Grant dateApr 26, 2022
Priority date
Expiry dateFeb 22, 2039

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21F15/005
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An internally injected replacement support room-type coal pillar recovery method is provided. During the recovery, the room-type coal pillars with an aspect ratio greater than 0.6 are divided into two parts: reserved coal pillars and pre-mined coal pillars. After the mining of the pre-mined coal pillars, a cemented filling material is injected into a goaf surrounded by the reserved coal pillars, and is stabilized to replace the coal pillars for support, and the reserved coal pillars are recovered. A mechanical model of the reserved coal pillars in a support overburden stage is established based on the Winkler beam theory, to obtain displacement and stress conditions of a roof of the reserved coal pillar in a support stage. A theoretical reserve-width of the reserved coal pillars is obtained according to a first strength theory of the roof and a criterion of ultimate strength of the reserved coal pillars.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.