On the instability of offshore foundations: theory and mechanism

Gao, Fu‐Ping; Li, JinHui; Qi, Wen-Gang; Chen, Hu

doi:10.1007/s11433-015-5745-9

Cited by 31 publications

(13 citation statements)

References 96 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The soil properties at every location at a site, however, cannot be known perfectly because the site investigation is often limited in offshore areas. The lack of understanding on the complex soil conditions was found to be a crucial factor on the failures of platforms (Brennan et al, 2006;Gao et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

Bearing capacity of spudcan foundations in a spatially varying clayey seabed

Huang³

et al. 2017

Ocean Engineering

Self Cite

View full text Add to dashboard Cite

A B S T R A C TSpudcan foundations are often pushed into a spatially varying non-homogeneous seabed to provide bearing capacity for a mobile jack-up platform. The natural variability of soil properties coupled with the complexity of loading conditions make determining the bearing capacity of spudcan foundations a challenging problem. A random finite element method is established to investigate the bearing capacity of a spudcan foundation embedded in a spatially varying clayey seabed when subjected to vertical, horizontal and moment loadings. A criterion is proposed for determining the characteristic value of the shear strength for the random seabed. Results indicate that the spatial variability in the clayey seabed significantly reduces the bearing capacity of a spudcan foundation. This reduction is more significant in the vertical bearing capacity than in the horizontal and moment bearing capacities. The mean bearing capacity is smaller for the clay with larger coefficient of variation of undrained shear strength. A characteristic value of mean minus a standard deviation of the undrained shear strength is capable to ensure the probability of failure is not greater than 5%. This study provide an evaluation method for the spatial variability effect of a clayey seabed, paving the way for a costeffective design of spudcan foundations.

show abstract

Section: Introductionmentioning

confidence: 99%

Bearing capacity of spudcan foundations in a spatially varying clayey seabed

Huang³

et al. 2017

Ocean Engineering

Self Cite

View full text Add to dashboard Cite

show abstract

“…The nondimensional expression of E s L 4 /E p I p is aimed to reflect the rigidity of the pile foundation [7,84], where I p denotes the second moment of area of a pile and E p I p Figure 6. Resistance components of a laterally loaded monopile foundation [82].…”

Section: Effects Of Local Scour On the Lateral Response Of A Monopilementioning

confidence: 99%

Local Scour around a Monopile Foundation for Offshore Wind Turbines and Scour Effects on Structural Responses

Qi¹,

Gao²

2020

Geotechnical Engineering - Advances in Soil Mechanics and Foundation Engineering

View full text Add to dashboard Cite

Monopile is the most commonly used foundation type for offshore wind turbines. The local scour at a monopile foundation generated by the incoming shear flow has significant influence on both quasi-static lateral responses and dynamic responses of the monopile. This chapter focuses particularly on characterizing the local scour in both spatial and temporal scales and revealing the scour mechanisms associated with the flow field around a monopile. The predicting methods for the equilibrium scour depth and the time scale of scour are detailed under various representative flow conditions in the marine environment. The scale effect while extrapolating the results of model tests to prototype conditions is highlighted. The local scour imposes significant influence not only on the deformation and stiffness of the monopile foundation, but also on the natural frequency and fatigue life of the structure system. Monopiles with diameters up to 10 m have become a feasible option as the industry is currently advancing into deeper waters. More meticulous considerations for monopile design associated with the scour depth prediction and evaluation of scour effects are still in need to efficiently minimize the cost while remaining safety simultaneously.

show abstract

“…图7给出了水平荷载作用下柔性桩和刚性桩的变形示意图(见Gao等人 [31] 现沿桩身外壁竖向分布的土阻力. Bekken [32] 和Byrne 等人 [26] 的数值研究结果表明刚性桩基底面和侧面受到的这些额外土阻力对桩基的位移等响应有重要影响.…”

Section: 基于参数化P-y曲线的桩基响应反演分析unclassified