Abstract
In order to apply the vertical shield machine for the construction of the large diameter vertical shaft, a new mechanism to carry the excavated particles on the excavated surface is necessary because the direction of excavation is equal to the one of gravity. In this study, a new method to carry the excavated particles by the rotating wall-jet from the initial position to the bottom center of the vertical shaft was proposed. A small experimental apparatus was made based on the similarity law and some experiments were carried out. It was confirmed that excavated particles were carried by the rotating wall-jet, and the proposed method by using the rotating wall-jet worked well. Furthermore, it was found that the cutter spoke should have the low inclination angle and water jet should be the one in air to achieve the high discharge efficiency.
