BORED TUNNELLING IN THE URBAN ENVIRONMENTS

This paper reviews the state of the art and recent developments in geotechnical aspects of bored tunneling in the urban environment. Various advances in tunnel construction techniques are highlighted, notably the increasing use of slurry and earth pressure balance shields. Methods of calculating the stability of tunnels are reviewed. In the context of tunneling in the urban environment, particular emphasis is given to ground movement associated with tunnel construction, their modeling and prediction, and their effects on buildings. Reference is made to case histories of tunnels constructed in a wide variety of ground conditions. Ground loading acting on tunnel linings is discussed. The paper focuses on three areas in which there have been significant developments in ground treatment in recent years: face reinforcement; slurry and earth pressure balance shield technology; and compensation grouting.