Laboratory Study of Integrated Wet-Towing of a Triple-Bucket Jacket Foundation for Far-Offshore Applications

Abstract

As a form of clean and low-carbon green energy, offshore wind power occupies an important position in the global energy structure. With the rapid development of the wind power industry, wind power projects gradually develop from offshore to far-offshore sea areas. The multi-bucket jacket foundation is a considerable foundation type for far off-shore projects, but high installation costs involving ship transportation with parted components and field installation has significantly hindered its wide application. In this study, based on a 6.7-MW triple-bucket jacket foundation (TBJF) project of a deep-sea wind farm in China, a new integrated wet-towing method of “jacket + triple-bucket foundation” composite structure was proposed, which is suitable for far long-distance transportation of far-offshore applications. The static-model test of both self-stability and wet-towing stability was conducted. Based on the test and the numerical results, the natural period of the foundation for different draft depths in hydrostatic water and the stability for different eccentric loads were first evaluated. Then, the effects of different wet-towing modes and sea conditions on the stability of the TBJF were investigated. Finally, the optimal wet-towing mode and applicable sea conditions for the TBJF structure were proposed.