Anti-liquefaction characteristics of composite bucket foundations for offshore wind turbines

Abstract

Occurrence of liquefaction in saturated sandy deposits under structure foundation can cause a wide range of structural damages from minor settlement to general failure because of bearing capacity loss. By comparing traditional foundations for offshore wind turbines, the soil inside and underneath the composite bucket foundation is subjected to the overburden pressure from the foundation self-weight and constrained by a half-closed bucket skirt. The objective of this paper is to clarify the effects of the soil-foundation interaction on the soil liquefaction resistance around the skirt and under the foundation. The dynamic response of the composite bucket foundation during earthquake, including coupled soil mode of porous media, is calculated using the ADINA finite-element program. A typical configuration of composite bucket foundation is used for the analysis, and two earthquake waves (peak ground accelerations of 0.035 g and 0.22 g) are applied as the base acceleration. The results show that the composite bucket foundation exhibited good resistance to seismic action by improving the anti-liquefaction capacity of the soil inside and under the foundation because of the overburden pressure of the self-weight and the constraint effect of the skirt. V C 2014 AIP Publishing LLC. [http://dx.

Features of Earthquake-Induced Seabed Liquefaction and Mitigation Strategies of Novel Marine Structures

“…To meet the various marine engineering challenges in the future and improve the liquefaction-resistant performance of the foundations, many innovative structure improvements have been proposed (Table 2). [64,68], large-scale prestressed concrete bucket foundation [76,77], tripod suction bucket foundations [78], modified suction caisson with external skirt [79,80], modified suction buckets with honeycomb compartment [81] Floating Deep water (>50 m)…”

“…According to the detailed geological surveys and the seismic fortification intensity of this site (7 degrees), Zhang et al used the ADINA program to analyze the liquefaction-resistance ability of soils below and inside this foundation and showed improvements due to the overburden pressure of the foundation and the constraint effect of the skirt [76,77]. They found that the concrete bucket foundation could still work after soil liquefaction.…”

Decoupled Modelling Approaches for Environmental Interactions with Monopile-Based Offshore Wind Support Structures

“…A three-dimensional finite-element model for a suction bucket foundation was presented by [136], whereas [137] presented a three-dimensional limit method for the stability analysis of suction buckets. The modelling of gravity-based and suction bucket foundations still require the definition of an applicable dynamic stiffness, accounting for cyclic degradation and liquefaction [138,139]. An increasing popularity of these alternative foundation concepts may instigate the need for industry-standard force-response relations as well.…”

Short‐Crested Wave‐Current Forces on Composite Bucket Foundation for an Offshore Wind Turbine

“…Many experimental and numerical studies have been conducted on offshore wind turbines, such as the monopile [4], jacket support structure [5], tripod [6], and floating offshore wind turbines [7]. In recent years, a large number of offshore windfarms have already been installed, are under construction, or are being planned in China [8], and a new kind of suction foundation called composite bucket foundation for offshore wind turbines was proposed by Tianjin University [9][10][11][12]. The composite bucket foundation takes full advantage of the high tensile capacity of the steel strand and the high compressive capacity of the concrete.…”