Abstract
Due to insufficient insights about the scour development around the STRABAG gravity foundation, the Franzius-Institute conducted small- and large-scale physical model tests in wave flumes on a scale of 1:50 and 1:17 in order to investigate the wave-induced scouring phenomena around the foundation and to design a scour protection system. The tests on scour development without a scour protection system show that the main areas which are vulnerable to scour are the contact areas of the foundation. Furthermore, the experiments show that a scour protection system is necessary for the given and investigated wave boundary conditions; the performance of the selected protection system using geotextile sand containers is verified. Additional numerical simulations indicate an amplification of the resulting flow around the foundation under combined loads (waves and current), but without significant change of the flow pattern
Highlights
Engineers planning and constructing Offshore Wind Turbines (OWTs) often have to deal with the problem that the development and depth of scours especially around complex foundations different from simple pile structures, are not really predictable, which leads to oversized dimensions for the foundation structures due to this lack in knowledge of scour progression and its final effects on structures
This paper focuses on the large-scale model tests dealing with the verification of the scour protection system
The tests on scour development without a scour protection system show that the main areas which are vulnerable to scour are the contact areas of the foundation
Summary
Engineers planning and constructing Offshore Wind Turbines (OWTs) often have to deal with the problem that the development and depth of scours especially around complex foundations different from simple pile structures (e.g. found in Sumer & Fredsøe 2002, Zanke et al 2011), are not really predictable, which leads to oversized dimensions for the foundation structures due to this lack in knowledge of scour progression and its final effects on structures. Due to insufficient insights about the flow and scour development around the STRABAG gravity foundation, the Franzius-Institute conducted small- and large-scale physical model tests in wave flumes on a scale of 1:50 and 1:17 in order to investigate the flow velocities and the wave-induced scouring phenomena around the foundation, as well as to design a scour protection system. Under the given boundary conditions of an extreme event with a recurrence interval of 50 years, the influence of waves is considered as being the main load on the scour protection system installed around the gravity foundation. The investigations on the hydraulic stability of the single sand containers against displacement, which are not presented in detail in this paper (for more details refer to Wilms et al 2011 and Werth et al 2012), show that the sand container type N1 is hydraulically stable and represents the minimum dimensions to withstand the given hydraulic wave boundary conditions.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
