Mechanised Tunnel Drives with optimised Support Pressure Control
Urban tunnelling is increasingly being characterised by mechanised drives with varying face support. High demands must be placed on the quality of design and foremost proper control for supporting the working face so that such projects can be executed safely in a tricky environment featuring a densely built-up area with extensive utilities as well as busy transportation facilities. The determining of the effects of fluid and earth pressure support and differences and problematic aspects in the proof concepts are explained. Two projects involving drives are used for exemplification.
Introduction
The technical and economic possibilities for the application of mechanised drives for all possible diameters are constantly growing. Tunnelling measures are consequently being more readily accepted in urban areas thanks to the application of these construction methods. In this connection the application of trenchless driving methods reduces the restrictions imposed on the surface to a minimum. Efficient supporting of the face represents a major influence for the success of a mechanised drive especially in water-saturated soft grounds. Proper adjustment of the support pressure is...