Suction bucket foundations are widely used in the offshore platform for the exploitation of the offshore petroleum and natural gas resources in the Bohai Bay of China. During winter seasons, ice sheets formed in Bohai Bay will impose strong impact and result in strong vibration on the platform. The measured frequency of the structural vibration of the platforms is 0.8~1.0 Hz. This paper describes a dynamic loading device developed on the geotechnical centrifuge at Tsinghua University and its application in modeling suction bucket foundation under the equivalent ice-induced vibration loadings.
The suction bucket is a large diameter cylinder, which is closed at the top and open at the bottom. Pump inlets and relief valves are mounted at the top. The cylinder is lowered to the sea floor under its own weight, with the relief valves open. After a sufficient penetration into the soil, the pump is started to generate differential pressure which drives the bucket into the soil at a required penetration depth. The pump and relief valves will be retrieved after installation. Experience shows that the application of the suction foundation in up to 3000 m of water would be possible.
The Suction installed bucket foundations are more and more commonly used for a variety of offshore structures. This type of foundation is beneficial both during installation and under extreme horizontal and moment loadings. It also has been gradually used as the foundation of the offshore platform in the exploitation of the offshore petroleum and natural gas resources in Bohai bay of China, as shown in Fig. 1. However, during winter seasons, ice sheets formed in the Bohai Bay will impose strong impact and result in serious vibration on the platform. The measured frequency of the structural vibration of the platforms is 0.8~1.0 Hz.
