DOI: 10.11799/ce202602006
Study on small coal pillar retention and surrounding rock control technology for secondary gob-side entry driving
QIAN Zheng
ZHAO Guangming
CHENG Xiang
MENG Xiangrui
YANG Shuo
Abstract：To rationally determine coal pillar width for gob-side entry driving under secondary mining conditions,a study was conducted on gob-side entry based on the roadway layout and engineering geological conditions of Qianyingzi Mine.Theoretical analysis,numerical simulation,and field practices were employed.The theoretical width range of the coal pillar was calculated using the limit equilibrium theory.Combined with numerical simulation,the distribution characteristics of stress and displacement in the surrounding rock of the gob-side entry under coal pillar widths of 4～8 m were analyzed.The results show that under these geological conditions,the reasonable coal pillar width ranges from 4 m to 8 m.When a 5～6 m coal pillar is retained,the stress state of the pillar improves,achieving a balance between economic benefits and roadway stability.Considering multiple factors,a 6 m coal pillar was determined to be optimal for the gob-side entry driving of the E3215 return airway.After implementing bolt-cable combined support for the small coal pillar and subsequent grouting,the maximum deformations of the roof-floor and two sides of the E3215 return airway were 154 mm and 196 mm,respectively.The overall deformation of the roadway remained within a controllable range.The 6 m coal pillar combined with the surrounding rock control technology for gob-side entry driving effectively ensures the stability of the double-roadway coal pillar and achieves long-term effective control of the surrounding rock.
Keywords：secondary gob-side entry drivingdouble district coal pillarnumerical simulationsurrounding rock control
Publication Date：2026-02-20
Online Publishing Date：2026-03-23(First online date of this platform, not the publication date of the document)
Pages：11( 39-49 )