New type flexible joint for the Osaka Port Yumeshima Tunnel Osamu Kiyomiya

This paper describes a newly invented flexible joint called Crown Seal Joint for the immersed tunnel at Osaka bay. Crown Seal Joint can absorb larger deformation between tunnel elements than conventional flexible joints. Crown Seal Joint mainly consists of a rubber block and flanges reinforced by plastic fibers. Basic performance of the joint was made clear by experimental and analytical tests in this study. From the experimental results, it was confirmed that Crown Seal Joint exhibits excellent performance to absorb design deformation and always keeps its neutral position at the joint. By FEM analysis, intolerable distortion is estimated in rubber material. It was also made clear that Crown Seal Joint reduces resulting stresses in the joint induced by earthquakes and differential settlement