Abstract
It is essential to use the space under narrow streets most effectively in big cities such as Tokyo.
The development of “the JIYIJU-DANMEN SHIELD METHOD”, which is a method to construct shield tunnels with non-circular sections such as elliptical, rectangular or horseshoe shapes, is under way for that purpose. As the first practical use, the Elliptical Shield Method using planetary diggers was applied to a trunk sewer tunnel under a narrow street in Tokyo.
In this paper, the design procedure of the shield machine and segments for the shield tunnel with elliptical shape is described together with experimental studies carried out to verify the said design procedure. Several important findings obtained through the actual construction are also described.
