Influence of Pile Diameter on Lateral Load Behavior and Failure Mechanisms of Large-Diameter Monopiles

Abstract

Increasing monopile diameter significantly alters lateral load response, and traditional design methods have already demonstrated limitations, while the influence mechanism of the diameter effect is still not in consensus. Using the three-dimensional finite element simulation, which is validated against centrifuge test results, the influence mechanism of the diameter effect is analyzed, and the related failure modes are also examined. It is found that the lateral bearing capacity of the monopile increases significantly with increasing pile diameter. The interaction of the soil plug and soil around the pile can enhance the nonlinear characteristics of the lateral load-displacement response. As the pile diameter increases, the deformation response of the pile evolves from flexible through semi-rigid to rigid behavior, and distinct failure modes are also developed. With the increase of pile diameter, the depth range of the wedge failure zone for flexible piles increases gradually, whereas for rigid piles, the depth range remains essentially unchanged, but the radius of the rotational failure zone significantly expands. The depth range of the full flow failure zone of semi-rigid piles progressively shrinks with the reduction in pile bending deformation. Failure modes can significantly affect the initial stiffness of the p-y curve. The initial stiffness exhibits the dependence on the pile diameter, embedment depth, and failure mode simultaneously.

Keywords

Diameter effect / Lateral bearing capacity / Failure mode / Initial stiffness

Author Contributions

Conceptualization, Y.W. and Y.G.; Methodology, Y.W. and Y.G.; Software, Y.W.; Validation, Y.G. and Q.Y.; Formal analysis, Y.W.; Investigation, Y.G.; Resources, Y.G.; Data Curation, Y.W.; Writing—Original Draft Preparation, Y.W.; Writing—Review and Editing, Y.G.; Visualization, Y.W., K.S., Y.J. and L.S.; Supervision, Y.G.; Project Administration, Y.G.; Funding Acquisition, Y.G. All authors have read and agreed to the published version of the manuscript.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data are contained within the article.

Funding

This research was funded by National Key R&D Program of China (2022YFC3005203) and National Natural Science Foundation of China (42072295).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

[1] Zhang X, Hu Z, Mu L, Tian W, Zhang Y, Huang P. Nonlinear Investigation of Laterally Loaded Piles in Layered Sand with a Modified Conical Strain Wedge Model. Ocean Eng. 2023, 272, 113874. doi:10.1016/j.oceaneng.2023.113874.

[2] Li T, Liang C, Liu R. Bearing Capacity Profile for Laterally Loaded Piles in Clay. Ocean Eng. 2025, 318, 120109. doi:10.1016/j.oceaneng.2024.120109.

[3] Zhang F, Dai G, Li X, Xu F, Gong W. Numerical Solution for the Laterally Loaded Rigid Piles Considering Resisting Force and Moment under Combined Loadings. Ocean Eng. 2024, 292, 116225. doi:10.1016/j.oceaneng.2023.116225.

[4] Wang L, Wu W, Zhang Y, Li L, Liu H, Naggar MHE. Nonlinear Analysis of Single Pile Settlement Based on Stress Bubble Fictitious Soil Pile Model. Num. Anal. Meth. Geomech. 2022, 46, 1187-1204. doi:10.1002/nag.3341.

[5] Wang L, Liu X, Wu W, El Naggar MH, Mei G, Wen M, et al. Nonlinear Analysis of Laterally Loaded Single Pile in Layered Soil Based on Conical Strain Wedge Model. Ocean Eng. 2023, 280, 114699. doi:10.1016/j.oceaneng.2023.114699.

[6] Gong X, Wang L. Offshore Geotechnical Engineering, 1st ed.; China Architecture and Building Press: Beijing, China, 2022; pp. 245-261.

[7] Ai ZY, Wang DS, Zhao YZ, Li PC. Laterally Loaded Piles and Pile Groups Partially Embedded in Transversely Isotropic Fractional Viscoelastic Saturated Soils. Eng. Anal. Bound. Elem. 2023, 146, 824-837. doi:10.1016/j.enganabound.2022.11.007.

[8] Malekjafarian A, Jalilvand S, Doherty P, Igoe D. Foundation Damping for Monopile Supported Offshore Wind Turbines: A Review. Mar. Struct. 2021, 77, 102937. doi:10.1016/j.marstruc.2021.102937.

[9] Sun Y. Experimental and Numerical Studies on a Laterally Loaded Monopile Foundation of Offshore Wind Turbine. Ph.D. Thesis, Zhejiang University, Hangzhou, China, 2016.

[10] Li W, Zhu B, Yang M. Static Response of Monopile to Lateral Load in Overconsolidated Dense Sand. J. Geotech. Geoenviron. Eng. 2017, 143, 04017026. doi:10.1061/(asce)gt.1943-5606.0001698.

[11] Ahmed SS, Hawlader B. Numerical Analysis of Large-Diameter Monopiles in Dense Sand Supporting Offshore Wind Turbines. Int. J. Geomech. 2016, 16, 04016018. doi:10.1061/(asce)gm.1943-5622.0000633.

[12] Hajialilue-Bonab M, Sojoudi Y, Puppala AJ. Study of Strain Wedge Parameters for Laterally Loaded Piles. Int. J. Geomech. 2013, 13, 143-152. doi:10.1061/(asce)gm.1943-5622.0000186.

[13] Hong Y, He B, Wang LZ, Wang Z, Ng CWW, Mašín D. Cyclic Lateral Response and Failure Mechanisms of Semi-Rigid Pile in Soft Clay: Centrifuge Tests and Numerical Modelling. Can. Geotech. J. 2017, 54, 806-824. doi:10.1139/cgj-2016-0356.

[14] Wang H, Fraser Bransby M, Lehane BM, Wang L, Hong Y. Numerical Investigation of the Monotonic Drained Lateral Behaviour of Large-Diameter Rigid Piles in Medium-Dense Uniform Sand. Géotechnique. 2023, 73, 689-700. doi:10.1680/jgeot.21.00149.

[15] Dai S, Han B, Wang B, Luo J, He B. Influence of Soil Scour on Lateral Behavior of Large-Diameter Offshore Wind-Turbine Monopile and Corresponding Scour Monitoring Method. Ocean Eng. 2021, 239, 109809. doi:10.1016/j.oceaneng.2021.109809.

[16] Dai S, Han B, Huang G, Gu X, Jian L, Liu S. Failure Mode of Monopile Foundation for Offshore Wind Turbine in Soft Clay under Complex Loads. Mar. Georesources Geotechnol. 2022, 40, 14-25. doi:10.1080/1064119x.2020.1855682.

[17] Reese LC, Cox WR, Koop FD. Analysis of Laterally Loaded Piles in Sand. In Proceedings of the 6th Annual Offshore Technology Conference, Houston, TX, USA,6-8 May 1974.

[18] Matlock H. Correlations for Design of Laterally Loaded Piles in Soft Clay. In Proceedings of the Ⅱ Annual Offshore Technology Conference, Houston, TX, USA,22-24 April 1970.

[19] American Petraleum Institute. Geotechnical and Foundation Design Considerations; API RP 2GEO; American Petroleum Institute: Washington, DC, USA, 2014.

[20] DNV GL. Support Structures for Wind Turbines; DNVGL-ST-0126; Det Norske Veritas: Oslo, Norway, 2021.

[21] Klinkvort RT. Centrifuge Modelling of Drained Lateral Pile-Soil Response. Ph.D. Thesis, Technical University of Denmark, Kongens Lyngby, Denmark, 2012.

[22] Sørensen SPH. Soil-Structure Interaction for Non-Slender, Large-Diameter Offshore Monopiles. Ph.D. Thesis, Aalborg University, Aalborg, Denmark, 2012.

[23] Choo YW, Kim D, Park J-H, Kwak K, Kim J-H, Kim D-S. Lateral Response of Large-Diameter Monopiles for Offshore Wind Turbines from Centrifuge Model Tests. Geotech. Test. J. 2014, 37, 20130081. doi:10.1520/gtj20130081.

[24] Amar Bouzid D. Numerical Investigation of Large-Diameter Monopiles in Sands: Critical Review and Evaluation of Both API and Newly Proposed p-y Curves. Int. J. Geomech. 2018, 18. doi:10.1061/(asce)gm.1943-5622.0001204.

[25] Georgiadis M, Anagnostopoulos C, Saflekou S. Centrifugal Testing of Laterally Loaded Piles in Sand. Can. Geotech. J. 1992, 29, 208-216.

[26] Wang L, Lai Y, Hong Y, Mašín D. A Unified Lateral Soil Reaction Model for Monopiles in Soft Clay Considering Various Length-to-Diameter (L/D) Ratios. Ocean Eng. 2020, 212, 107492, doi:10.1016/j.oceaneng.2020.107492.

[27] Zhu J, Yu J, Huang M, Shi Z, Shen K. Inclusion of Small-Strain Stiffness in Monotonic p-y Curves for Laterally Loaded Piles in Clay. Comput. Geoteth. 2022, 150, 104902. doi:10.1016/j.compgeo.2022.104902.

[28] Terzaghi K. Evaluation of Coefficients of Subgrade Reaction. Géotechnique. 1988, 5, 296-326. doi:10.1680/geot.1955.5.4.297.

[29] Randolph M, Gourvenec S. Offshore Geotechnical Engineering, 1st ed.ed.; Spon Press: New York, NY, USA, 2011; pp. 273-283.

[30] He R, Kaynia AM. Winkler Spring Coefficients for Laterally Loaded Piles. Comput. Geoteth. 2024, 170, 106264. doi:10.1016/j.compgeo.2024.106264.

[31] Wang H. Lateral Behaviour of Offshore Monopile and Bucket Foundations in Sand. Ph.D. Thesis, Zhejiang University, Hangzhou, China, 2020.

[32] Byrne BW, Burd HJ, Zdravkovic L, Abadie CN, Houlsby GT, Jardine RJ, et al. PISA Design Methods for Offshore Wind Turbine Monopiles. In Proceedings of the Offshore Technology Conference, Houston, TX, USA, 26 April 2019.

[33] Byrne BW, Houlsby GT, Burd HJ, Gavin KG, Igoe DJP, Jardine RJ, et al. PISA Design Model for Monopiles for Offshore Wind Turbines: Application to a Stiff Glacial Clay Till. Géotechnique. 2020, 70, 1030-1047. doi:10.1680/jgeot.18.p.255.

[34] Wang H, Wang LZ, Hong Y, He B, Zhu RH. Quantifying the Influence of Pile Diameter on the Load Transfer Curves of Laterally Loaded Monopile in Sand. Appl. Ocean Res. 2020, 101, 102196. doi:10.1016/j.apor.2020.102196.

[35] Zhu B, Xiong G, Liu J, Sun Y, Chen R. Centrifuge Modelling of a Large-Diameter Single Pile under Lateral Loads in Sand. Chin. J. Geotech. Eng. 2013, 35, 1807-1815.

[36] Zhang X, Zhou R, Xu C. Study on Corrected P-y Curve Model of Pile Foundation of Offshore Wind Turbines. Acta Energiae Solaris Sin. 2023, 44, 290-297.

[37] Achmus M, Kuo Y-S, Abdel-Rahman K. Behavior of Monopile Foundations under Cyclic Lateral Load. Comput. Geoteth. 2009, 36, 725-735. doi:10.1016/j.compgeo.2008.12.003.

[38] Cheng X, Wang T, Zhang J, Liu Z, Cheng W. Finite Element Analysis of Cyclic Lateral Responses for Large Diameter Monopiles in Clays under Different Loading Patterns. Comput. Geoteth. 2021, 134, 104104. doi:10.1016/j.compgeo.2021.104104.

[39] Sun X, Yang H, Li S, Cui X. Stable Node-Based Smoothed Finite Element Method for 3D Contact Problems. Comput. Mech. 2022, 69, 787-804. doi:10.1007/s00466-021-02114-1.

[40] Chen Z, Zhang Z, Li W, Wang T, Zhang J. Numerical Study on the Base Shear Force-Displacement Relationship for Laterally Loaded Monopiles in Dense Sand. Ocean Eng. 2023, 286, 115527. doi:10.1016/j.oceaneng.2023.115527.

[41] Han F, Ganju E, Salgado R, Prezzi M. Effects of Interface Roughness, Particle Geometry, and Gradation on the Sand-Steel Interface Friction Angle. J. Geotech. Geoenviron. Eng. 2018, 144. doi:10.1061/(asce)gt.1943-5606.0001990.

[42] Han F, Ganju E, Prezzi M, Salgado R. Closure to “Effects of Interface Roughness, Particle Geometry, and Gradation on the Sand-Steel Interface Friction Angle” by Fei Han, Eshan Ganju, Rodrigo Salgado, and Monica Prezzi. J. Geotech. Geoenviron. Eng. 2019, 145. doi:10.1061/(asce)gt.1943-5606.0002172.

[43] Hu Q, Han F, Prezzi M, Salgado R, Zhao M. Lateral Load Response of Large-Diameter Monopiles in Sand. Géotechnique 2022, 72, 1035-1050. doi:10.1680/jgeot.20.00002.

[44] Han F, Ganju E, Prezzi M, Salgado R, Zaheer M. Axial Resistance of Open-Ended Pipe Pile Driven in Gravelly Sand. Géotechnique 2020, 70, 138-152. doi:10.1680/jgeot.18.p.117.

[45] Zhang Y, Andersen KH. Soil Reaction Curves for Monopiles in Clay. Mar. Struct. 2019, 65, 94-113. doi:10.1016/j.marstruc.2018.12.009.

[46] Fu D, Zhang Y, Aamodt KK, Yan Y. A Multi-Spring Model for Monopile Analysis in Soft Clays. Mar. Struct. 2020, 72, 102768. doi:10.1016/j.marstruc.2020.102768.

[47] Wang H, Wang L, Hong Y, Mašín D, Li W, He B, et al. Centrifuge Testing on Monotonic and Cyclic Lateral Behavior of Large-Diameter Slender Piles in Sand. Ocean Eng. 2021, 226, 108299. doi:10.1016/j.oceaneng.2020.108299.

[48] Zhu B, Li T, Xiong G, Liu JC. Centrifuge Model Tests on Laterally Loaded Piles in Sand. Int. J. Phys. Model. Geo. 2016, 16, 160-172. doi:10.1680/jphmg.15.00023.

[49] Haiderali AE, Madabhushi G. Evaluation of Curve Fitting Techniques in Deriving p-y Curves for Laterally Loaded Piles. Geotech. Geol. Eng. 2016, 34, 1453-1473. doi:10.1007/s10706-016-0054-2.

[50] Fan C-C, Long JH. Assessment of Existing Methods for Predicting Soil Response of Laterally Loaded Piles in Sand. Comput. Geoteth. 2005, 32, 274-289. doi:10.1016/j.compgeo.2005.02.004.

[51] Nan B. Studies on Modified P-y Curves Method of Monopile Based on the Degradation Stiffness Model of Sand. Master’s Thesis, Zhejiang University, Hangzhou, China, 2019.

[52] Augustesen AH, Brødbæk KT, Møller M, Sørensen SPH, Ibsen LB, Pedersen TS, et al. Numerical Modelling of Large-Diameter Steel Piles at Horns Rev. In Proceedings of the Twelfth International Conference on Civil, Structural and Environmental Engineering Computing, Funchal, Madeira, Portugal,1-4 September 2009.