The First Construction of SPS (Single Pile Structure) in Japan

SPS is a single pile dolphin which can absorb the most of berthing energy or bear mooring force through its large deflection. The pile of SPS is designed to utilize the lateral resistance of the ground beyond the elastic region. It is generally necessary to use high-tensile steel for the material of pile; however, thanks to its structural simplicity and flexibility, SPS is superior to conventional dolphins consisted of multiple piles in terms of the construction period and cost. The first SPS in Japan for the use of breasting dolphin has been constructed for an LNG vessel of 130, 000m3. This paper describes the characteristics of SPS, its design method, comparison with conventional dolphins. In addition, construction of the SPS and lateral loading experiments for the purpose of design verification are reported.