Small-displacement behavior of offshore wind power monopiles subjected to static lateral loading
-
摘要: 针对海上风电桩径9 m的超大直径单桩基础，采用离心模型试验与数值仿真相结合方法，研究砂土地基中不同锚固深度工况下单桩基础在小变位条件下的水平静力承载特性。结果表明，随锚固深度增加，桩身旋转中心逐渐下移，且桩身水平位移与倾角沿桩身分布的非线性趋势逐渐增强。不同锚固深度工况下桩侧p-y曲线间的差异随深度逐渐加大，在趋势上，p-y曲线随锚固深度增大由外凸型向内凹型转变；在量值上，同一深度处初始割线模量间可相差4倍。这一差异的原因在于，同一深度处桩体发生相同侧位移时，锚固更浅的桩体周围土体内部径向位移、环向位移的影响范围较小，土体应变较大，进而呈现较大的水平抗力。研究成果有助于深化对大直径单桩基础承载机制的认识，进而为桩体设计优化提供理论基础。Abstract: The centrifuge tests and numerical simulations are carried out to explore the small-displacement behavior of 9 m-diameter offshore wind power large-scale monopiles with various embedment depths. The results show that as the embedment depth increases, the rotation center gradually moves downward, and the nonlinear characteristics of lateral displacement and rotation angle distributions along piles are gradually enhanced. The difference among p-y curves of monopiles with various embedment depths gradually increases with depth. In terms of trend, the p-y curve changes from convex to concave with the increasing embedment depth. In terms of magnitude, the initial secant modulus at the same depth can differ by 4 times. It can be explained as follows: when the same lateral displacement occurs at the same depth, the monopiles with relatively smaller embedment depths show smaller influence zones of both radial and circumferential displacements in the surrounding soils, and then the soil strain is larger, which eventually contributes to a larger horizontal resistance on piles. The research results help to deepen the understanding of the load-transfer mechanisms of large-diameter monopiles, and to provide a theoretical basis for the optimization of associated design approaches.
-
Keywords:
- centrifuge test /
- finite difference method /
- monopile /
- p-y curve /
- embedment depth
-
-
![]()
图 2 离心模型试验粉砂材料级配曲线
Figure 2. Grain-size distribution curve of silty sands used in centrifuge tests
![]()
图 4 离心模型试验水平加载力时程曲线（模型尺度）
Figure 4. Time histories of horizontal loading force in centrifuge tests (model scale)
![]()
图 5 离心模型试验桩体侧位移时程曲线（模型尺度）
Figure 5. Time histories of lateral displacement (model scale)
![]()
图 6 离心模型试验与数值模拟结果对比：H-θ'关系
Figure 6. Comparison between experimental and numerical results: H-θ' relationship
![]()
图 7 离心模型试验与数值模拟结果对比：桩身弯矩分布
Figure 7. Comparison between experimental and numerical results: bending moment distributions of piles
![]()
图 8 不同锚固深度桩体H-θ0关系
Figure 8. H-θ0 relationships of monopiles with different embedment depths
![]()
图 9 L_27 m桩体侧位移及倾角分布图
Figure 9. Lateral displacement and rotation angle distributions of L_27 m
![]()
图 10 L_72 m桩体侧位移及倾角分布图
Figure 10. Lateral displacement and rotation angle distributions of L_72 m
![]()
图 12 不同锚固深度桩体侧位移及倾角分布
Figure 12. Lateral displacement and rotation angle distributions of monopiles with various embedment depths
![]()
图 13 具备不同锚固深度桩体的p-y曲线对比
Figure 13. Comparison of p-y curves of monopiles with various embedment depth
![]()
图 14 不同锚固深度桩体初始割线模量分布
Figure 14. Initial secant modulus distributions of monipiles with different embedment depths
![]()
图 15 L_27 m桩体25 m深度处表面应力分布
Figure 15. Distribution of stresses on pile surfaces at a depth of 25 m for L_27 m
![]()
图 16 L_72 m桩体25 m深度处表面应力分布
Figure 16. Distribution of stresses on pile surfaces at a depth of 25 m for L_72 m
![]()
图 17 L_27 m桩体25 m深度土体径向及环向位移场
Figure 17. Radial and circumferential displacement fields at a depth of 25 m for L_27 m
![]()
图 18 L_72 m桩体25 m深度土体径向及环向位移场
Figure 18. Radial and circumferential displacement fields at a depth of 25 m for L_72 m
表 1 粉砂物理力学参数
Table 1 Properties of silty sand
相对质量密度 干密度/
(g·cm-3)相对密度/
%最大干密度/(g·cm-3) 最小干密度/
(g·cm-3)黏聚力/
kPa内摩擦角/
(°)2.69 1.55 62 1.87 1.21 4 33 
下载: 导出CSV
-
[1] 刘金昊, 张帆, 戴国亮. 基于静力触探的黏土中桩基p-y曲线研究[J]. 太阳能学报, 2023, 44(2): 172-180. LIU Jinhao, ZHANG Fan, DAI Guoliang. Research on p-y curve of pile foundation in clay based on cpt data[J]. Acta Energiae Solaris Sinica, 2023, 44(2): 172-180. (in Chinese)
[2] 王立忠, 洪义, 高洋洋, 等. 近海风电结构台风环境动力灾变与控制[J]. 力学学报, 2023, 55(3): 567-587. WANG Lizhong, HONG Yi, GAO Yangyang, et al. Dynamic catastrophe and control of offshore wind power structures in typhoon environment[J]. Chinese Journal of Theoretical and Applied Mechanics, 2023, 55(3): 567-587. (in Chinese)
[3] 王卫, 闫俊义, 刘建平. 基于海上风电试桩数据的大直径桩p-y模型研究[J]. 岩土工程学报, 2021, 43(6): 1131-1138. doi: 10.11779/CJGE202106017 WANG Wei, YAN Junyi, LIU Jianping. Study on p-y models for large-diameter pile foundation based on in situ tests of offshore wind power[J]. Chinese Journal of Geotechnical Engineering, 2021, 43(6): 1131-1138. (in Chinese) doi: 10.11779/CJGE202106017
[4] 胡中波, 翟恩地, 罗仑博, 等. 基于静载试验的海上风电钢管桩砂土p-y曲线研究[J]. 太阳能学报, 2019, 40(12): 3571-3577. HU Zhongbo, ZHAI Endi, LUO Lunbo, et al. Study on p-y curves of steel pipe piles for offshore wind farms in sand based on in situ tests[J]. Acta Energiae Solaris Sinica, 2019, 40(12): 3571-3577. (in Chinese)
[5] WANG H, LEHANE B M, BRANSBY M F, et al. Field and numerical study of the lateral response of rigid piles in sand[J]. Acta Geotechnica, 2022, 17(12): 5573-5584. doi: 10.1007/s11440-022-01532-6
[6] MCADAM R A, BYRNE B W, HOULSBY G T, et al. Monotonic laterally loaded pile testing in a dense marine sand at Dunkirk[J]. Géotechnique, 2020, 70(11): 986-998. doi: 10.1680/jgeot.18.PISA.004
[7] CHOO Y W, KIM D. Experimental development of the p-y relationship for large-diameter offshore monopiles in sands: centrifuge tests[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2016, 142(1): 04015058. doi: 10.1061/(ASCE)GT.1943-5606.0001373
[8] 朱斌, 熊根, 刘晋超, 等. 砂土中大直径单桩水平受荷离心模型试验[J]. 岩土工程学报, 2013, 35(10): 1807-1815. http://cge.nhri.cn/article/id/15299 ZHU Bin, XIONG Gen, LIU Jinchao, et al. Centrifuge modelling of a large-diameter single pile under lateral loads in sand[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(10): 1807-1815. (in Chinese) http://cge.nhri.cn/article/id/15299
[9] TRUONG P, LEHANE B M, ZANIA V, et al. Empirical approach based on centrifuge testing for cyclic deformations of laterally loaded piles in sand[J]. Géotechnique, 2019, 69(2): 133-145.
[10] LI Z S, BLANC M, THOREL L. Effects of embedding depth and load eccentricity on lateral response of offshore monopiles in dense sand: a centrifuge study[J]. Géotechnique, 2023, 73(9): 811-825.
[11] RICHARDS I A, BYRNE B W, HOULSBY G T. Monopile rotation under complex cyclic lateral loading in sand[J]. Géotechnique, 2020, 70(10): 916-930.
[12] DNV-OS-J101. Offshore standard: Design of offshore wind turbine structures[S]. DNV-OS-J101, 2014.
[13] 海上风电场工程风电机组基础设计规范: NB/T 10105—2018[S]. 北京: 中国水利水电出版社, 2018. Code for Design of Wind Turbine Foundations of Offshore Wind Power Projects: NB/T 10105—2018[S]. Beijing: China Water & Power Press, 2018. (in Chinese)
[14] American Petroleum Institute. Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms-Working Stress Design[S]. Washington D C: American Petroleum Institute Publishing Services, 2005.
[15] TAK KIM B, KIM N K, JIN LEE W, et al. Experimental load–transfer curves of laterally loaded piles in nak-Dong river sand[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2004, 130(4): 416-425.
[16] 朱斌, 朱瑞燕, 罗军, 等. 海洋高桩基础水平大变位性状模型试验研究[J]. 岩土工程学报, 2010, 32(4): 521-530. http://cge.nhri.cn/article/id/12426 ZHU Bin, ZHU Ruiyan, LUO Jun, et al. Model tests on characteristics of ocean and offshore elevated piles with large lateral deflection[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(4): 521-530. (in Chinese) http://cge.nhri.cn/article/id/12426
[17] LI W C, ZHU B T, YANG M. Static response of monopile to lateral load in overconsolidated dense sand[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2017, 143(7): 04017026.
[18] ACHMUS M, ABDEL-RAHMAN K. Finite element modelling of horizontally loaded monopile foundations for offshore wind energy converters in Germany[M]//Frontiers in Offshore Geotechnics. Perth: Taylor & Francis, 2005
[19] ZHANG Z, WANG W, ZHANG X, et al. An innovative experimental device for characterizing the responses of monopiles subjected to complex lateral loading[C]// Proceedings of the 8th International Symposium on Deformation Characteristics of Geomaterials. Porto, 2023.
[20] WANG W, ZHANG Z T, ZHU Xiao Y, et al. A device for centrifuge tests on foundations of offshore wind turbines[J]. Engineering Mechanics, 2021, 38(4): 44-53
[21] REESE L C, COX W R, KOOP F D. Analysis of Laterally Loaded Piles in Sand[C]// Offshore Technology Conference. Houston, 1974.
-
期刊类型引用(4)
1. 王艳，薛逸翔，朱鹏. 电动联合渗透反应屏障修复污染土壤的研究进展. 安全与环境学报. 2024(01): 330-344 . 
百度学术
2. 周细霞，刘朝淑，孙荣国. Fe(II)改性蒙脱石对土壤汞的吸附固定机理探究. 贵州师范大学学报(自然科学版). 2024(04): 63-74 . 百度学术
3. 王艳，张李奕岚，朱鹏，王恒宇. 电动法去除污染土中重金属铬的试验研究. 安全与环境学报. 2024(08): 3251-3259 . 百度学术
4. 李宗春，郭苗章，谌伟艳. 某废弃矿山重金属污染土壤治理约束优化研究. 环境科学与管理. 2023(05): 71-75 . 百度学术
其他类型引用(3)
-
其他相关附件
计量
- 文章访问数: 0
- HTML全文浏览量: 0
- PDF下载量: 0
- 被引次数: 7
