Mechanism and technology of pressure relief by roof cutting for gob-side entry retention with small coal pillars in thick hard roof
Year: 2025
Type: article
Abstract: To address the challenges of strong dynamic pressure disturbances and surrounding rock instability in gob-side entries with small coal pillars under conditions of thick hard roof, this study takes the 16202 working face of Wuhua Mining as the engineering background. A comprehensive investigation into the pressure relief mechanism and optimization of roof cutting and entry protection technology was conducted through theoretical analysis, numerical simulation, and industrial trials. A mechanical model of a short cantilever beam for the roof under pressure relief via roof cutting was established, revealing the three-stage characteristics of thick hard roof fracture and movement. The mechanical mechanism by which roof cutting reduces the load on the coal pillar by 33% was elucidated. A technical system of "large-diameter borehole roof cutting combined with synergistic cable support" was proposed, which innovatively optimizes the roof cutting height, angle, and coal pillar width. Numerical simulations indicated that the stress concentration factor and surrounding rock deformation for a 10m coal pillar are significantly superior to those of the 6–9m schemes. Industrial trials verified that the maximum roof subsidence was only 112mm, with no floor heave observed. The cable bolts experienced stable loads between 138.8–163.8kN, and the stability of the support structure was improved by 40%. The results demonstrate that this technology effectively controls the lateral cantilever structure of the hard roof, eliminates the risk of rock burst, achieves an entry cross-section integrity exceeding 95%, and provides technical support for the safe and efficient mining of working faces with thick hard roofs.
Source: Results in Engineering
Authors: Weilong Wang, Hailong Sun, Jianwei Li, Eryu Wang
Institution: Inner Mongolia University of Science and Technology
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,940
Funders: Education Department of Inner Mongolia Autonomous Region, National Natural Science Foundation of China, Natural Science Foundation of Inner Mongolia, Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region, Department of Science and Technology of Inner Mongolia
OpenAlex ID: W4416542848