海上风电结构长期服役于恶劣的海洋环境中,损伤不断累积,严重时导致整体失效。现有损伤检测方法可以识别结构损伤,但未考虑桩-土作用、冲刷效应对结构动力特性的影响,若直接应用于实际工程容易导致损伤误判。基于交叉模型交叉模态法(CMCM法),考虑桩-土作用和冲刷效应,优化了桩基的边界条件,发展了CMCM结构损伤检测方法。建立了单桩-土体有限元模型,结合已有试验数据,验证了砂土地基条件下数值模型及检测方法的可靠性。进一步地,研究了桩-土作用、冲刷效应对整体结构模态的影响,并基于不同地基假定的基准模型,对数值模型中的结构损伤进行检测。结果表明,考虑桩-土作用、冲刷效应后的地基刚度降低,从而导致结构频率降低、模态振型改变;该模型边界更符合实际工程地基状态,排除导致误判的干扰因素后,结构损伤位置、程度均可被准确识别,提升了CMCM方法的准确性和工程适用性。
关键词:海上风机;损伤检测;模态分析;地基;冲刷
Abstract
Offshore wind turbine structures continually serve in atrocious ocean environment, and the damage continues to accumulate, leading to overall failure in severe cases. Existing damage detection methods can identify structural damage, but ignore the influence of pile-soil interaction and scour effect on the structural dynamic features. If it is directly applied to the actual project, it will easily cause misjudgment of damage. Based on the cross-model cross-mode method(CMCM method), considering the pile-soil interaction and scouring effect, the pile boundary conditions were optimized, and the CMCM structure damage detection method was developed. The pile-soil finite element model was established, combined with the existing test data, to verify the numerical model and detection method under the sand foundation. Furthermore, pile-soil interaction and scouring effect on the structural modal was studied, and the numerical model damage was detected based on the baseline model for different foundation assumptions. Results show that the foundation stiffness decreases after considering the pile-soil interaction and scouring effects, which leads to a decrease in the structure frequency and a change in the mode shape; The model boundary is more in line with the actual engineering foundation status; After the interference items are eliminated, the structural damage location and severity can be accurately identified, which improves the accuracy and engineering applicability of the CMCM method.
Key words: offshore wind turbine; damage detection; modal analysis; foundation; scour
关键词
海上风机 /
损伤检测 /
模态分析 /
地基 /
冲刷
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Key words
offshore wind turbine /
damage detection /
modal analysis /
foundation /
scour
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参考文献
[1] ESTEBAN M D, LOPEZ-GUTIERREZ J S, NEGRO V, et al. Offshore wind foundation design: some key issues[J]. Journal of Energy Resources Technology. 2015, 137(5): 051211(1-6).
[2] ARANY L, BHATTACHARYA S, MACDONALD J, et al. Closed form solution of Eigen frequency of monopile supported offshore wind turbines in deeper waters incorporating stiffness of substructure and SSI[J]. Soil Dynamics and Earthquake Engineering, 2016, 83:18-32.
[3] LI Z Q, CHEN S J, HAO M, et al. Design defect of wind turbine operating in typhoon activity zone[J]. Engineering Failure Analysis, 2013, 27(165-172).
[4] 李华军,刘福顺,王树青. 海洋平台结构模态分析与损伤检测[M]. 北京: 科学出版社, 2017.
[5] HU S L J, LI H J, WANG S Q. Cross-model cross-mode method for model updating[J]. Mechanical Systems and Signal Processing, 2007, 21(4): 1690-1703.
[6] LI H J, WANG J R, HU S L J. Using incomplete modal data for damage detection in offshore jacket structures[J]. Ocean Engineering, 2008, 35(17-18): 1793-1799.
[7] LIU F S, WANG P, WANG W Y, et al. Model updating and damage detection using cross model cross mode method for 3D frame structures[J]. Advanced Materials Research, 2011, 243-249: 5369-5373.
[8] 李英超,张敏,李华军. 利用不完备实测模态修正杆系结构约束边界条件[J]. 工程力学, 2013, 30(01): 288-294.
LI Yingchao , ZHANG Min , LI Huajun. model updating for constraint boundary conditions of member structures using incomplete measured modes[J]. Engineering Mechanics, 2013, 30(01): 288-294.
[9] 贺广零. 考虑土-结构相互作用的风力发电高塔系统地震动力响应分析[J]. 机械工程学报, 2009, 45(07): 87-94.
HE Guangling. Seismic response analysis of wind turbine tower systems considering soil-structure interaction[J]. Journal of Mechanical Engineering, 2009, 45(07): 87-94.
[10] LOMBARDI D, BHATTACHARYA S, MUIR W D. Dynamic soil-structure interaction of monopile supported wind turbines in cohesive soil[J]. Soil Dynamics and Earthquake Engineering, 2013, 49: 165-180.
[11] 陈跃庆,吕西林,李培振,等. 不同土性的地基-结构动力相互作用振动台模型试验对比研究[J]. 土木工程学报, 2006(05): 57-64.
CHEN Yueqing, LV Xilin, LI Peizhen, et al. Comparative study on the dynamic soil-structure interaction system with various soils by using shaking table model tests[J]. China Civil Engineering Journal, 2006(05): 57-64.
[12] MCCLELLAND B, FOCHT J A. Soil modulus for laterally loaded piles[J]. Soil Mechanics and Foundation Division Journal, 1956, 82(4):1-22.
[13] PRENDERGAST L J, HESTER D, GAVIN K, et al. An investigation of the changes in the natural frequency of a pile affected by scour[J]. Journal of Sound and Vibration, 2013, 332(25): 6685-6702.
[14] LIN C, HAN J, BENNETT C, et al. Analysis of laterally loaded piles in soft clay considering scour-hole dimensions[J]. Ocean Engineering, 2016, 111: 461-470.
[15] 梁发云,王琛,贾承岳,等. 冲刷深度对简支桥模态参数影响的模型试验[J]. 振动与冲击, 2016, 35(14): 145-150.
LIANG Fayun, WANG Chen, JIA Chenyue, et al. Model test on the influence of scour depth on modal parameters of simply supported bridge[J]. Journal of Vibration and Shock, 2016, 35(14): 145-150.
[16] 陈琛,马宏旺,李玉韬,等. 冲刷对海上风电单桩基础自振频率影响的研究[J]. 振动与冲击, 2020, 39(22): 16-22.
CHEN Chen, MA Hongwang, LI Yutao, et al. Effects of scour on the natural frequency of offshore wind turbine structures. Journal of Vibration and Shock, 2020, 39(22): 16-22.
[17] Chen X G, Niu X D, Xu Q Y, et al. Method for monitoring scour depth of pile foundations based on modal identification [J]. Smart Materials and Structures, 2021, 30(7): 075008.
[18] Bisoi S, Haldar S. Dynamic analysis of offshore wind turbine in clay considering soil-monopile-tower interaction[J]. Soil Dynamics and Earthquake Engineering, 2014, 63: 19-35.
[19] CLOUGH R W, PENZIEN J. 结构动力学[M]. 王光远. 北京:高等教育出版社, 2006.
[20] FRISWELL M I, MOTTERSHEAD J E. Finite element model updating in structural dynamics[M]. London: Kluwer Academic Publishers, 1995.
[21] HARDIN B O, DRNEVICH V P. Shear modulus and damping in soil: Measurement and parameter effects[J]. Soil Mechanics and Foundation Division Journal, 1972, 98(6): 603-624.
[22] VESIC A B. Beams on elastic subgrade and the Winkler's hypothesis[C]. // Proceedings 5th International Conference on Soil Mechanics and Foundation Engineering. Paris: Dunod, 1961. 845-850.
[23] ASHFORD S A, JUIRNARONGRIT T. Evaluation of pile diameter effect on initial modulus of subgrade reaction[J]. Geotechnical and Geo-environmental Engineering, 2003, 129: 234-242.
[24] LIN C, BENNETT C, HAN J, et al. Scour effects on the response of laterally loaded piles considering stress history of sand[J]. Computers and Geotechnics, 2010, 37(7-8): 1008-1014.
[25] KONG X , CAI C S , HOU S. Scour effect on a single pile and development of corresponding scour monitoring methods[J]. Smart Materials & Structures, 2013, 22(5): 055011.
[26] VOS L D, ROUCK J D, TROCH P, et al. Empirical design of scour protections around monopile foundations. Part2: Dynamic approach[J]. Coastal engineering, 2012, 60:p.286-298.
[27] LEBLANC C, HOULSBY G T, BYRNE B W. Response of stiff piles in sand to long-term cyclic lateral loading[J]. Geotechnique, 2010, 60(2):7.
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