Sequential Excavation for Tunnels and Shafts

Tunneling employing a sequential excavation philosophy represents a unique intersection between planning, design and construction. It depends on the behavior of the ground and the construction methods, size of the opening and support measures, and the rate of advancement. It allows adaptation to changing conditions, for which the team must work collaboratively and flexibly, applying the observational method to share and manage project risk. Over the last five decades there has been a rapid advancement in computational capabilities, understanding of ground pressures and methods of support, construction materials such as shotcrete, techniques, methods, and equipment to excavate soil and rock, and instrumentation to measure, monitor, and display force and displacement in near real-time. Sequential excavation can now be used in a wider range of ground conditions, particularly in urban settings. This book shows how analysis and rigorous thought in design, backed up by calculations, can manage project risks. Empirical, analytical, and numerical methods are illustrated with supporting examples, and practical rule-of-thumb guidance is offered. The mathematics is also presented along with selected equations. It is for professionals, and will also suit advanced students.