Effects of strain softening on the penetration resistance of offshore bucket foundation in nonhomogeneous clay

Xiao, Zhong; Fu, Dengfeng; Zhou, Zefeng; Lu, Yumin; Yan, Yue

doi:10.1016/j.oceaneng.2019.106594

Cited by 32 publications

(7 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With an increase in the penetration depth, the difference in the uplift height of the soil inside the steel cylinder gradually increased, indicating that most of the soil discharged from the cylinder wall entered the cylinder, and only a small part flowed to the outside of the steel cylinder. This is basically consistent with an offshore bucket foundation investigation by Xiao et al [36].…”

Section: Influence Of Wall Thickness On Soil Flowsupporting

confidence: 92%

Penetration Performance of Steel Cylinders in Sand Foundations

Xu,

Ruan,

Jiang

2023

Applied Sciences

View full text Add to dashboard Cite

In order to study the effect of wall thickness on the penetration process of steel cylinders, we carried out physical tests and numerical simulations of the penetration process of steel cylinders with different wall thicknesses in sandy soil foundations, focusing on analyzing the penetration force and soil uplift during the penetration process of steel cylinders. The results show that the coupled Eulerian-Lagrangian (CEL) approach can be used to simulate the penetration process of steel cylinders. During the penetration of steel cylinders with different wall thicknesses, the relationship between the penetration force and penetration depth can be approximated by a quadratic function. The larger the wall thickness is, the larger the plug volume inside the steel cylinder during penetration. The research results can provide support for the design and construction of steel cylinders.

show abstract

Section: Influence Of Wall Thickness On Soil Flowsupporting

confidence: 92%

Penetration Performance of Steel Cylinders in Sand Foundations

Xu,

Ruan,

Jiang

2023

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…Because the field variables of Eulerian element EC3D8R cannot be called directly in VUSDFLD, the temperature, as a dummy variable, is called in the VUSDFLD subroutine as an initial state variable to allow a variation in temperature that is identical to the initial undrained shear strength, S u0 . This approach has been used in the study of the penetration resistance of bucket foundations and has proven to be effective [35]. In the computational domain, an initial temperature field that is identical to S u0 is provided by an "*initial conditions" keyword, while in the void domain, the temperature is zero.…”

Section: Detail Methodologymentioning

confidence: 99%

“…The used Eulerian analysis technology provides a large deformation calculation method in an explicit finite element scheme [32]. In each incremental step of the Eulerian analysis, a Lagrangian calculation is first performed, and then the new variables are mapped to the fixed Eulerian background mesh to achieve material flow [33][34][35]. This technology is effective for applications involving extreme deformation, up to and including fluid flow.…”

Section: Introductionmentioning

confidence: 99%

Convenient Method for Large-Deformation Finite-Element Simulation of Submarine Landslides Considering Shear Softening and Rate Correlation Effects

Xie,

Xu,

Xiu

et al. 2023

JMSE

View full text Add to dashboard Cite

Submarine landslides pose a serious threat to the safety of underwater engineering facilities. To evaluate the safety of undersea structures, it is important to estimate and analyze the sliding processes of potential submarine landslides. In this study, a convenient model for simulating submarine landslide processes is established by using Abaqus Eulerian large deformation technology with an explicit finite element framework. The VUSDFLD Fortran subroutine is used to consider the strain-softening and rate-dependency characteristics of soil shear strength. The proposed method is validated by comparing its results with experimental data and those of mainstream numerical methods. Then, the results of a dynamic analysis of typical potential submarine landslides in the Shenhu sea area are analyzed using the proposed method. Case studies are carried out under different soil shear strength distributions, and the influence of initial stress is also analyzed. The shear strain-softening and rate-dependency effects are highly involved in the runout process. The simulated landslide’s failure mode is consistent with the geophysical interpretation of existing landslide characteristics.

show abstract

“…Wang et al [6] used the arbitrary Lagrangian-Eulerian (ALE) method to simulate the installation process of suction buckets and compared the difference in penetration resistance and soil heaving under different installation methods. Xiao et al [7] studied the changes in penetration resistance and soil flow mechanism during the penetration process of a single bucket foundation, considering the strain softening and rate effect of soil using the coupled Eulerian-Lagrangian (CEL) method. The adverse effects of bucket penetration-induced soil heaving and softening on the ultimate bearing capacity were also studied [8].…”

Section: Introductionmentioning

confidence: 99%

“…Large deformation numerical analysis is required to model the installation of the bucket foundation with inner bucket and cruciform skirts in clay. In the literature, there are three large deformation numerical methods by which to simulate the installation of the bucket foundation in clay; these include the ALE method [7], the remeshing and interpolation technique by small strain (RITSS) [8], and the CEL method [7]. For the ALE method, a new mesh is created when the elements have obvious distortion.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Soil Heaving and Penetration Resistance of Bucket Foundation with Inner Bucket and Cruciform Skirts

Xiao

Wang³

et al. 2023

JMSE

Self Cite

View full text Add to dashboard Cite

Since concrete is cheaper and more resistant to corrosion than steel, the wide-shallow concrete bucket foundation is being used extensively in ocean engineering. By adding the inner bucket and cruciform skirts, both the bearing capacity and rigidity of the wide-shallow concrete bucket foundation increase significantly. When compared to the hollow steel bucket foundation, the inclusion of thicker skirts, as well as the addition of inner bucket and cruciform skirts, would cause changes to the soil flow mechanism, resulting in soil heave within each compartment and changes in soil strength evolution and penetration resistance during installation in clay. In order to study the influence of the addition of the inner bucket and cruciform skirts on the soil heaving inside each compartment, soil softening and penetration resistance, three-dimensional large deformation finite element (LDFE) models for the bucket foundation with and without inner bucket, and cruciform skirts considering soil remolding were established using the Coupled Eulerian–Lagrangian (CEL) approach. It was found that the inner bucket significantly changes the soil flow and softening of the soil during penetration of the bucket foundation. According to the theoretical analysis and numerical results, the diameter of the optimal inner bucket is equal to 5/8 of the outer diameter. The adhesion coefficient observed in this study falls within the range of 0.5 to 0.8, which is higher than the theoretical value of 0.25 that assumes the soil is fully remolded. The reason for this discrepancy is that the soil is only partially remolded during the actual installation of the bucket foundation. The neglect of the softening of the soil or considering the soil as completely softened will result in significant variation in the predicted penetration resistance; hence, partial softening of the soil should be taken into account.

show abstract

Effects of strain softening on the penetration resistance of offshore bucket foundation in nonhomogeneous clay

Cited by 32 publications

References 18 publications

Penetration Performance of Steel Cylinders in Sand Foundations

Penetration Performance of Steel Cylinders in Sand Foundations

Convenient Method for Large-Deformation Finite-Element Simulation of Submarine Landslides Considering Shear Softening and Rate Correlation Effects

Investigation of Soil Heaving and Penetration Resistance of Bucket Foundation with Inner Bucket and Cruciform Skirts

Contact Info

Product

Resources

About