A shaft tunnel driven by pipe jacking was adopted in order to provide ventilation to the underground reservoir tunnel under the national highway in Yokohama, Japan. Downward excavation of the 2000mm ID ventilation tunnel starts from ground surface and reaches to the crown of the existing reservoir tunnel, which is located 87.8m deep. Depression angle of the tunnel is set as 75.6 degree. Pore water pressure at the arrival is 0.66MPa. This project is one of the largest in this type of tunnels in Japan. As Oogihara et al. (2003) described on details of the shield machine, this paper focuses on equipment and facilities adopted in the project and construction methodology of the inclined pipe jacking.
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