Numerical Analysis on Minimal Safe Distance between Two Opposite Excavation Faces of Deep-Buried Tunnel

Abstract:

When the distance between two opposite excavation face is too small, the explosive load of one excavation face may causes rock failure of the other excavation face and result in engineering accidents. In this paper, the dynamic response of rock pillar between two opposite excavation faces during one explosive excavation cycle is investigated. An aftereffect function is adopted to reflect the viscoelastic properties of deep rock mass, and the explicit difference scheme of stress field is derived and then implemented by Matlab programs. The transient stress field of rock pillar is computed by coupling the initial stress field and the explosive waves. The analogies between the minimal safe distance and those influence factors such as explosive excavation load, rock mechanical properties, in-situ stresses, are fulfilled by this method. The back analysis results of a real case indicate that the results of presented method agree well with the actual situation.

• Periodical: Applied Mechanics and Materials (Volumes 353-356)
• Pages: 1315-1320
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.353-356.1315
• Online since: August 2013
• Authors: Wen Tao Chen*, Yi Huan, Peng Xian Fan
• Keywords: Deep-Buried Tunnel, Explosive Excavation, Minimal Safe Penetration Distance, Opposite Excavation

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