Abstract
The Sydney Harbour Tunnel for a solution to Sydney's cross-harbour traffic problem is now under construction by immersed tube (IMT) tunnel method, on the east side of the existing Harbour Bridge. IMT units are cast in drydock at a distance of 90 kilometers from Sydney and towed to Sydney Harbour to be sunk. In this towing situation, IMT units are encountered severe waves because of open-sea towing. Therefore, stability of the unit against the wave-indused motions is the principal subject. This paper deals with the characteristic of unit motions and towing force based on model towing tests, and is considered to be applicable in real works.
