Structural resistiveness against wave action of immersed tunnel element that is constructed at Naha Port is investigated. Hydraulic tests and numerical simulation (CADAMAS-Surf) are conducted on the characteristics of motion of a immersed tunnel element. It is found that the required weight for stability of immersed tunnel element, and that the motion of the tube is stopped by reclamation of the sidewall. Using these results, a rapid emplacement method is developed and No.1 tube's emplacement was done using this method.
