Experimental Approach Towards Investigating Cyclic Load Response of a Suction Anchor

Abstract Suction caissons are becoming a popular choice for offshore wind turbine (OWT) foundation projects. They can be utilized either as foundations for fixed-bottom wind turbines or as anchors for floating wind turbines. Despite being implemented for several years in the oil and gas industry, experience from some recent OWT projects indicates that the design and installation process for this foundation is still one of the most challenging and expensive operations. Anchors for floating wind turbines are often installed in cohesionless seabed and subjected to complex environmental loading. One of the most critical loading conditions is cyclic tensile loading acting simultaneously with a net tensile load, which may cause large accumulated tensile displacement. However, tensile behaviour of suction anchors in sand is not well understood. This paper presents a review of research on suction anchor installation and tensile loading in sand and outlines initial development of an experimental set-up to investigate this issue. The expected outcome of this test set-up is to provide insight into installation and critical cyclic load cases for the design of suction anchors for floating wind turbines.