Weak Rock Tunneling

Weak rock tunnelling is a permanent challenge to tunnel engineers. Severe failure and excessive displacements may encompass large roof and/or wall zones if uncontrolled. This book was written to be of some help to tunnel engineers involved with weak rocks. Using simple statics rules, it explains the mechanics associated with the underground excavation and support installation. Also, it includes a simple PC based code and design charts for early planning and design of common vehicular tunnels as well as for convergence measurements during construction. This simplified model was derived from well-established Rock Mechanics principles and engineering practice. It simulated the overall equilibrium at tunnel heads and is applied to quasi-elliptical cross-sectrions, taking into account not only the lining stiffness and lining installation procedure but also the mechanical properties, geostatic stresses and hydraulic conditions of the rock surrounding the tunnel.