Risks associated with long deep tunnels

• Published in: Rock Engineering Risk pp. 201 - 340
• Main Authors: Hudson, John A., Feng, Xia-Ting
• Format: Book Chapter
• Language: English
• Published: United Kingdom CRC Press 2015; Taylor & Francis Group
• Subjects: CIVIL ENGINEERING, SURVEYING & BUILDING; Waste management; Aleatory Uncertainty; Surrounding Rock Mass; Destress Blast; Headrace Tunnels; Pilot Tunnel; Large Deformation; Water Inrush; Rock Mass; Tunnel Face; Rock Stress; Rockburst Risk; Class Iii; Rockburst Events; Drainage Tunnel; Gotthard Base Tunnel; Jinping II Hydropower Station; Jinping Ii; Access Tunnel; Chlorite Schist; Yalong River; Excavation Damaged Zone; Deep Tunnels; Tunnel Sections; Microseismic Monitoring; TBM Excavation
• ISBN: 1138027014; 9781138027015
• DOI: 10.1201/b18395-11

Recalling that the previous Chapters have included content on the introduction and background to the rock engineering risk subject, explanations of uncertainty and risk, the risk factors before, during and after construction, rock engineering systems and auditing, rock fractures and rock stress, we now present a major case example concerning the risks associated with long deep tunnels, both in general and specifically with regard to the Jinping II hydropower station in China. In this context, we begin by discussing both the epistemic and aleatory uncertainties and methods to assess and mitigate the risk for such long deep tunnels including rockbursts and water inrushes. Then, we explain in detail how the concepts have been applied for the specific case of the deep 17 km long tunnels at the Jinping II project.