Open AccessEnergy Variation Law and Rockburst Characteristics of Coal under Cyclic Loading
Author(s) -
Hongjun Guo,
Ming Ji,
Dapeng Liu,
Mengxi Liu,
Gaofeng Li,
Jingjing Chen,
Hongjie Chen
Publication year - 2021
Publication title -
shock and vibration
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.418
H-Index - 45
eISSN - 1875-9203
pISSN - 1070-9622
DOI - 10.1155/2021/5528555
Subject(s) - coal , classification of discontinuities , coal mining , deformation (meteorology) , geotechnical engineering , rock blasting , mining engineering , law , materials science , structural engineering , forensic engineering , geology , engineering , composite material , waste management , mathematical analysis , mathematics , political science
Coal mining involves numerous challenges and safety risks owing to the complex engineering properties of coal bodies, which include discontinuities, heterogeneity, and anisotropy. In this paper, the strain energy during the coal deformation process is redivided in combination with cyclic loading and unloading tests to determine the energy evolution law and discuss the rockburst tendency characteristics. The results show that the elastic strain energy, and particularly the base-material strain energy, consistently dominates during the energy adjustment process, which is an important indicator of rockburst tendency. The elastic energy index and rebound deformation index also show that moderate plastic deformation (e.g., crack expansion and local penetration) can reduce the rockburst tendency level and prevent rockburst accidents. On the basis of the obtained results, precracking and pressure relief measures of blasting are adopted on site in advance of the working face, and good safety and economic benefits are achieved. These findings, thus, provide an important engineering reference for mines under similar conditions.