Citation

Tian S, Xu X, Li Z. Safety Sci. 2019; 115: 208-214.

Copyright

(Copyright © 2019, Elsevier Publishing)

DOI

10.1016/j.ssci.2019.02.006

PMID

unavailable

Abstract

Roof-fall accidents, happening near the driving faces of coal roadways, threaten the safety of construction operatives. Taking Jining No. 3 Coal Mine of Yanzhou Coal Mining Group Corp. (Jining City, Shandong Province, China) as the research object, we analysed the roof structure near the driving face of a coal roadway. Meanwhile, the disaster-inducing mechanism was studied through mechanical analysis and numerical simulation. The results demonstrated that the artificial support structure and C-shaped bracing structure co-determine the safety of the roof. With the length of unsupported roof (LUR) increasing, the control effects of the two structures experienced three stages of behaviour (i.e. a superimposed support stage, collaborative support stage, and independent support stage) on the roof. In these, coal at the top corners became looser and the roof span increased. As a result, the safety of the unsupported roof deteriorated, with the rear part being the first to become damaged, thus triggering a roof-fall accident. Based on the above conclusion, the research proposed safety-control criteria for an unsupported roof, and thus provides a critical basis for assessing support strength and ensuring the safety of tunneling construction operations.

Language: en

Keywords

Coal-roadway tunneling; Disaster-inducing process; Roof structure; Safety-control criterion