Laboratory Study on the Propagation of Horizontal Edge Cracks in Rock-like Material

DOI

10.2991/coal-18.2018.11How to use a DOI?

Keywords

pre-existing edge crack, rock-like material, fracturing, propagation, uniaxial compression, floor failure

Abstract

Rock fracture propagation is a major hazard for mining and tunnel excavation in fractured rock masses or coal seams. This paper describes a study of investigating the mechanisms and pathways of rock fracture under uniaxial compression. A rock-like material which consists of model gypsum, water and diatomaceous earth at a mass ratio of 165:75:2 were used. The uniaxial compression strength of the material decreased with the increase of the length of pre-existing horizontal edge crack. During the tests, wing (tensile) cracks were first observed at the tip of the pre-existing horizontal edge crack. This was followed by secondary cracks as the loading increasing. The final failure of the specimens however was dominated by tensile cracks throughout the specimens. Due to the sudden crack initiations in the specimens, the loading stress in the specimen varies changes stepwise and AE energy and amplitude showed abrupt changes when crack initiated. When the crack initiation occurred, the loading stress of the specimens showed a notable retreat in the stress-strain curve, and the recorded AE energy and amplitude showed a sharp spike. Understanding the horizontal edge crack propagation characteristics and fracture mechanisms is a key step for the prevention and control of floor water inrush in longwall mining panels.

Copyright

© 2018, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Baoliang Zhang
AU  - Baotang Shen
AU  - Shaojie Chen
AU  - Xizhen Sun
PY  - 2018/10
DA  - 2018/10
TI  - Laboratory Study on the Propagation of Horizontal Edge Cracks in Rock-like Material
BT  - Proceedings of the 9th China-Russia Symposium "Coal in the 21st Century: Mining, Intelligent Equipment and Environment Protection" (COAL 2018)
PB  - Atlantis Press
SP  - 63
EP  - 67
SN  - 2352-5401
UR  - https://doi.org/10.2991/coal-18.2018.11
DO  - 10.2991/coal-18.2018.11
ID  - Zhang2018/10
ER  -