Width Design of Small Coal Pillar of Gob‐Side Entry Driving in Soft Rock Working Face and Its Application of Zaoquan Coal Mine

Abstract

Reasonable width of gob-side coal pillar can reduce the waste of coal resources and is conducive to roadway stability. According to the distribution of internal and external stress fields at the working face, a method for determining the width of gob-side coal pillar was proposed. The coal pillar and roadway should be set within the internal stress field, and support is provided through the anchored part and the intact part of the coal pillar. The method was used in the design of the coal pillar at No. 130205 working face of Zaoquan Coal Mine. The calculation results indicated that the width of a coal pillar suitable for gob-side entry is 6.0 m. It is reasonable to arrange the roadway and coal pillar in the low-stress zone with a width of 11 m. During tunnelling of roadway and stoping of the working face, the deformation of the roadway increased with a reduction in the distance from the working face. Even during stoping of the working face, there was an approximately 1.5 m intact zone in the coal pillar. This indicates that the proposed method of designing small coal pillar of gob-side entry driving is reliable.

Study on surrounding rock failure mechanism and rational coal pillar width of the gob‐side coal roadway under influence of intense dynamic pressure

“…The gob‐side coal roadway will be threatened by the strong dynamic pressure during the mining of this working face 4,5 . To ensure the safety of the gob‐side coal roadway, a certain width of section coal pillar will be reserved when the roadway is driven 6 . A reasonable width of the coal pillar is crucial to the surrounding rock control of the roadway.…”

“…4,5 To ensure the safety of the gob-side coal roadway, a certain width of section coal pillar will be reserved when the roadway is driven. 6 A reasonable width of the coal pillar is crucial to the surrounding rock control of the roadway. If the coal pillar is too small, the bearing capacity of the coal pillar is low and it is difficult to ensure the safety of the roadway.…”

Study on Stress Characteristics and Supporting Countermeasures of Surrounding Rock in Roadway Formed by Composite Roof Cutting in Three-soft Coal Seam

“…Especially under high ground stress, an increasing greater width has been retained for coal pillars [2], most of which cannot be recovered, being the primary cause of coal resource losses [3]. To improve the recovery rate of coal resources, many experts and scholars have put forward small pillar mining [4] and mining through filling entry retaining [5], but they are still coal pillar mining in essence.…”

Determination of coal pillar width for gob‐side entry driving in isolated coal face and its control in deep soft‐broken coal seam: A case study

“…[2][3][4] GED has been widely used in China, Canada, Germany, South Africa, and other countries. The width design 5 of narrow coal pillar of GED is the key to stability control. Therefore, it is of great guiding significance for safe and efficient production of coal mine by analyzing the stress distribution and plastic characteristics of surrounding rock, and reasonably designing narrow coal pillar width and control technology.…”