Probabilistic Study of Offshore Monopile Foundations Considering Soil Spatial Variability
Publication: ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering
Volume 8, Issue 3
Abstract
The objective of this paper is to investigate how the spatially varied soil stiffness affects the ultimate lateral load and failure mechanism of monopiles embedded in soft clay. Responses of a laterally loaded monopile in spatially varied soils were simulated by a three-dimensional finite-element analysis combined with random field theory. The influence of the coefficient of variation () and the correlation distance () regarding the stiffness parameters was investigated. Results revealed that the spatial structure has an impact on stiffness distribution and leads to a significant discrepancy between the ultimate load of the spatially random soil and the uniform soil. The assumption of uniformity in stiffness yields an overestimation of the ultimate load and an excessively high cost of construction. Both the and intensify the discrepancy and increase the probability of the foundation exceeding the ultimate limit states. Due to the spatial pattern of soil, the failure plane exhibits an unsymmetrical pattern and an irregular shape in random soil instead of a symmetrical shape in uniform soil. The results provide a better explanation of the failure mechanisms of monopile foundations and reveal the importance of considering the reliability indices in the designing process.
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Data Availability Statement
All data, models, and codes that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The financial contributions of the National Natural Science Foundation of China (No. 51909287) and Guangdong provincial Natural Science Foundation of China (No. 2020A1515010872) are gratefully acknowledged.
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Information
Published In
ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering
Volume 8 • Issue 3 • September 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: May 4, 2021
Accepted: Apr 30, 2022
Published online: Jul 4, 2022
Published in print: Sep 1, 2022
Discussion open until: Dec 4, 2022
ASCE Technical Topics:
- Analysis (by type)
- Continuum mechanics
- Dynamic loads
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Failure analysis
- Foundations
- Geomechanics
- Geotechnical engineering
- Lateral loads
- Mathematics
- Pile foundations
- Piles
- Probability
- Soft soils
- Soil analysis
- Soil mechanics
- Soil properties
- Soils (by type)
- Solid mechanics
- Static loads
- Statics (mechanics)
- Stiffening
- Structural behavior
- Structural dynamics
- Structural engineering
- Ultimate loads
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