2091. Numerical and experimental simulation of damaged rock with randomly oriented cracks by shock disturbance

Wanrong Wu1, Lei Lou2

1, 2Central South University, State Key Laboratory of High Performance Complex Manufacturing, Changsha 410083, China

2College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China

2Corresponding author

E-mail: 1wanrong@163.com, 2zgloulei@163.com

Received 17 December 2015; received in revised form 24 May 2016; accepted 28 June 2016

DOI https://doi.org/10.21595/jve.2016.16741

Abstract. The aim of this study is to investigate the effect of shock-disturbed cracks on the dynamic fragmentation of granite. Considering the complex behavior of rock materials, the Walsh’s model was revisited and extended by including the stress effect required to close an initially open crack and examining the unloading process in detail. This analysis leads to closed‑form expressions for loading and unloading portions of the effective Young’s modulus, as functions of the crack density, characteristic aspect ratio, and crack friction coefficient. Subsequently, the effective Young’s modulus and cutting force are simulated and the influence of cracks is studied. The analysis results with different crack density and disturbed frequency are compared in terms of effective Young’s modulus and cutting force. Finally, the tool and damaged rock model with randomly oriented cracks by shock disturbed at a different frequency was demonstrated by the test. The good agreement between the simulation results and experimental data demonstrates the validity of the simulation method.

Keywords: damaged rock, cracks, shock disturbed, aspect ratio, cutting force.

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Cite this article

Wu Wanrong, Lou Lei Numerical and experimental simulation of damaged rock with randomly oriented cracks by shock disturbance. Journal of Vibroengineering, Vol. 18, Issue 5, 2016, p. 2867‑2879.

 

© JVE International Ltd. Journal of Vibroengineering. Aug 2016, Vol. 18, Issue 5. ISSN 1392-8716