Vertical bearing behaviour of the composite bucket shallow foundation of offshore wind turbines

Abstract

A composite bucket shallow foundation (CBSF) has been proposed by Tianjin University to adapt the offshore soft geological conditions of China for wind turbines. Vertical bearing capacity modelling and observation tests regarding the CBSF are performed. The test results are accompanied by numerical simulations to provide a better understanding of the failure mechanism of the CBSF. The upper limit of the vertical bearing capacity of the bucket foundation is derived through the upper bound theorem of classical plasticity theory according to the failure mechanism. The soil damage rate is specified as a new empirical parameter in the formula and is defined as the rate between the thickness of the soil that is broken inside the foundation and the radius of the foundation, which indicates the range of soil failure. Furthermore, the range of the soil damage rate is obtained through vertical bearing capacity model tests. The relationship of the bearing capacity factor N q and N c with the friction angle is also discussed under the specific soil damage rates. V C 2015 AIP Publishing LLC. [http://dx.

Field experiments on wet tows of an integrated transportation and installation vessel with two bucket foundations for offshore wind turbines

“…The new foundation innovated by a research group at Tianjin University is based on the conventional bucket foundation and, for the first time, which are proposed as a composite bucket foundation for offshore wind turbines suitable for the marine area offshore of China (high wind speeds and soft ground) Liu et al, 2014;Lian et al, 2012Lian et al, , 2014Zhang et al, 2014Zhang et al, , 2015Zhang et al, ,a, 2015b. The only CBF for a fully operational wind turbine of 2.5 MW was installed at the offshore test facility in Qidong City in the southeast of Jiangsu province in China in 2010.…”

Penetration and Pullout Capacity of Low‐Skirted Suction Caissons

“…A new type of umbrella suction caisson was developed by Liu and Li [27] and Li et al [28], and its bearing capacity and dynamic characteristics were investigated by performing model tests and numerical simulation. A composite bucket shallow foundation was proposed by Tianjin University to adapt the offshore soft geological conditions of China for wind turbines, and the bearing capacity and technical advantages of composite bucket foundation have been investigated by performing a series of model tests and finite element analysis [29,30].…”

Failure Envelopes of Composite Bucket Foundation for Offshore Wind Turbines under Combined Loading with considering Different Scour Depths

“…Liu et al [11] systematically investigated the effects of the dimensional parameter on the resistance of the composite bucket foundation under moment loads, as well as the failure mechanism of the composite bucket foundation and the locations of the foundation rotation points. Liu et al [12] investigated the ultimate bearing capacity of the composite bucket foundation under vertical loading with the aid of the model test and classical plasticity theory. Liu et al [13] studied the horizontal bearing capacity characteristics of the composite bucket foundation in silty clay soil through a large size model test.…”