冰激结构频率锁定振动的发生机理及简单分析方法

屈衍; 黄子威; 邹科; 尹昊阳; 张大勇

doi:10.6052/0459-1879-20-382

冰激结构频率锁定振动的发生机理及简单分析方法

doi: 10.6052/0459-1879-20-382

屈衍^*,2), ,,
黄子威^*,
邹科^*,
尹昊阳^*,
张大勇^†

^*南方科技大学前沿与交叉科学研究院,广东深圳 518055
^††大连理工大学工业装备结构分析国家重点实验室,辽宁大连 116024

基金项目: 1) 国家自然科学基金(41976195);国家自然科学基金(51679033);国家研发计划(2016YFC0303400);工业装备结构分析国家重点实验室开放课题(GZ19120)

详细信息

作者简介:
2) 屈衍,副研究员,主要研究方向：极地海洋工程. E-mail: quy3@sustech.edu.cn

通讯作者:
屈衍

中图分类号: P751,P731.15
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- 被引次数: 0
出版历程
- 收稿日期: 2020-11-19
- 刊出日期: 2021-03-10

MECHANISM AND SIMPLE ANALYSIS METHOD OF ICE INDUCED FREQUENCY LOCK-IN VIBRATION OF OFFSHORE STRUCTURES

Qu Yan^{*,2)
, ,},
Huang Ziwei^*,
Zou Ke^*,
Yin Haoyang^*,
Zhang Dayong^†

^*Academy for Advanced Interdisciplinary Studies,Southern University of Science and Technology,Shenzhen 518055,Guangdong,China
^††State Key Laboratory of Structure Analysis for Industrial Equipment,Dalian University of Technology, Dalian 116024,Liaoning,China

摘要

摘要: 冰激结构频率锁定振动是冰区海洋工程结构的危险工况.对频率锁定振动过程的传统机理解释没有体现这一过程的全部物理特征,导致现有的分析方法无法准确分析这一问题.本文基于对现场测量结果的分析,提出了一种海冰韧性损伤-破碎过程与结构振动耦合导致频率锁定振动的机理.该机理认为,海冰在直立结构频率锁定振动过程中发生韧性损伤-破碎行为,海冰的韧性损伤-破碎与结构运动相位耦合,导致了频率锁定振动. 海冰对结构作用产生的载荷为锯齿形,作用过程可以分为加载和卸载两个阶段,其中加载阶段时间长度约为卸载阶段3倍以上.在加载阶段,结构从平衡位置先与海冰运动方向相反振动到反向最大振幅位置后回摆,然后与海冰同向运动到正向最大振幅位置,这段过程中海冰与结构接触部位内部产生裂纹并扩展但未发生主要的破碎,在此阶段海冰发生韧性损伤;在卸载阶段,结构从最大振幅位置向平衡位置回摆,结构与海冰运动方向相反,这一过程中应变速率的突然增大导致裂纹加速扩展并失稳开裂,此时带有韧性损伤的海冰发生破碎.基于这一新的机理解释,本文提出了一种冰激结构频率锁定振动幅值的简单分析方法.该方法认为海冰破碎长度是频率锁定振动的关键参数. 理想状态下,海冰破碎长度约为结构水线处振动幅值的2.2倍.当冰速接近海冰破碎长度与结构自振周期的比值时,结构会发生频率锁定振动.该方法对评估海洋工程结构频率锁定振动的发生概率及疲劳损伤具有指导意义.
- 冰激振动 /
- 频率锁定 /
- 韧性损伤-破碎 /
- 海冰破碎长度
Abstract: Ice induced frequency lock-in vibration of offshore structures has been recognized as a serious load condition in ice regions. The traditional mechanism cannot fully explain all the physical phenomena in the frequency lock-in vibration, nor can a reasonable analysis method be obtained. Based on the analysis of full scale measurement data, this paper proposes a new mechanism of frequency lock-in vibration caused by the coupling of sea ice ductile damage-collapse failure and structural vibration. It is believed that the ductile damage-collapse failure of sea ice occurs during the frequency lock-in vibration of vertical structures, which is coupled with the phase of structural motion, resulting in frequency lock-in vibration. Saw-teeth-shape ice load is caused by the action between sea ice and the structure. The action process can be divided into loading and unloading stages, the loading stage takes about 3 times the time of the unloading stage. In the loading stage, the structure moves against ice from equilibrium position to its maximum negative amplitude and then moves back together with ice at the same direction to its maximum positive amplitude. Cracks are formed in the contact part of the sea ice and the structure, but not collapse. The sea ice undergoes ductile damage at this stage. In the unloading stage, the structure moves in the opposite direction to the sea ice, swinging back from the maximum amplitude to its equilibrium position. The sudden increase of strain rate leads to the accelerated propagation and instable fracture of cracks. The sea ice with ductile damage collapses at this stage. Based on the new mechanism explanation, this paper presents a simple analysis method of ice induced frequency lock-in vibration of offshore structures. It is considered that the sea ice break length is the key parameter of frequency lock-in vibration. In the ideal situation, the sea ice break length is about 2.2 times of the vibration amplitude at the waterline of the structure. When the ice velocity is close to the ratio of sea ice break length to the natural vibration period of the structure, frequency lock-in vibration will occur. This method has guiding significance for evaluating the occurrence probability of frequency lock-in vibration and fatigue damage of offshore structures.
- ice induced vibration /
- frequency lock-in /
- ductile damage-collapse failure /
- sea ice break length

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参考文献(47)

[1]	Peyton HR. Sea ice strength. Final Report of Naval Research Arctic Project for Period 1958-1965, 1966,285
[2]	Engelbrektson A. Observations of a resonance vibrating lighthouse structure in moving ice// Proceedings of the Seventh International Conference on Port and Ocean Engineering under Arctic Conditions, Helsinki, Finland, 1983,2:855-864
[3]	Engelbrektson A, Jansson JE. Field observations of ice action on concrete structures in the Baltic Sea. Concrete International, 1985,7(8):48-52
[4]	M??tt?nen M. Field observations of ice action on concrete structures in the Baltic Sea. Concrete International, 1975, 345-355
[5]	杨国金. 海洋工程灾害与环境载荷. 中国海洋平台, 1995,10(5):202-204 (Yang Guojin. Marine engineering disaster and environmental load. China Offshore Platform, 1995,10(5):202-204 (in Chinese))
[6]	Jefferies MG, Wright WH. Dynamic response of “Molikpaq” to ice-structure interaction. OMAE 1988, Houston, TX, U.S.A., 1988,4:201-220
[7]	M??tt?nen M. Ice induced frequency lock-in vibrations-converging towards consensus// Proceedings of the International Conference on Port and Ocean Engineering under Arctic Conditions, POAC, 2015
[8]	Bjerk?s M, Meese A. Ice induced vibrations-observations of a full-scale lock-in event// Proceedings of the Twenty-Third International Offshore and Polar Engineering International Society of Offshore and Polar Engineers (ISOPE). Anchorage, Alaska, 2013, 1272-1279
[9]	Nord TS, Samardzija I, Hendrikse H, et al. Ice-induced vibrations of the Norstr?msgrund lighthouse. Cold Regions Science and Technology, 2018,155(12):237-251
[10]	K?rn? T. Laboratory and medium scale data analyses// Ice Induced Vibrations JIP, Olav Olsen. KARNA Research and Consulting, 2011, OO-11179-1.2.1
[11]	M??tt?nen M, Marjavaara P, Saarinen S, et al. Ice crushing tests with variable structural flexibility. Cold Regions Science and Technology, 2011,67(3):120-128
[12]	O'Rourke BJ, Jordaan IJ, Saarinen RS, et al. Experimental investigation of oscillation of loads in ice high-pressure zones, Part 1: Single indentor system. Cold Regions Science and Technology, 2016,124(8):25-39
[13]	Toyama Y, Sensu T, Minami M, et al. Model tests on ice-induced self-excited vibration of cylindrical structures. VTT Symposium (Valtion Teknillinen Tutkimuskeskus), 1983,28(28):834-844
[14]	Sodhi D. Ice-structure interaction with segmented indentors//Proc. 11th IAHR Ice Symp. Banff, Alberta, 1992,2:909-929
[15]	黄焱, 史庆增, 宋安. 冰激柔性直立桩结构振动的模型试验. 天津大学学报, 2007,40(5):530-535 (Huang Yan, Shi Qingzeng, Song An. Model test of ice-induced vibration on compliant verticalpile. Journal of Tianjin University, 2007,40(5):530-535 (in Chinese))
[16]	Gagnon RE. An inside look at ice-crushing induced vibration and lock-in// Proceedings of the 21st International Conference on Port and Ocean Engineering under Arctic Conditions (POAC'11), Montreal, Canada, 2011
[17]	陈晓东, 崔海鑫, 王安良, 等. 基于巴西盘试验的海冰拉伸强度研究. 力学学报, 2020,52(3):625-634 (Chen Xiaodong, Cui Haixin, Wang Anliang, et al. Experimental study on sea ice tensile strength based on Brazilian tests. Chinese Journal of Theoretical and Applied Mechanics, 2020,52(3):625-634 (in Chinese))
[18]	刘璐, 尹振宇, 季顺迎. 船舶与海洋平台结构冰载荷的高性能扩展多面体离散元方法. 力学学报, 2019,51(6):1720-1739 (Liu Lu, Yin Zhenyu, Ji Shunying. High-performance dilated polyhedral based DEM for ice loads on ship and offshore platform structures. Chinese Journal of Theoretical and Applied Mechanics, 2019,51(6):1720-1739 (in Chinese))
[19]	刘璐, 龙雪, 季顺迎. 基于扩展多面体的离散单元法及其作用于圆桩的冰载荷计算. 力学学报, 2015,47(6):1046-1057 (Liu Lu, Long Xue, Ji Shunying. Dilated polyhedra based discrete element method and its application of ice load on cylindrical pile. Chinese Journal of Theoretical and Applied Mechanics, 2015,47(6):1046-1057 (in Chinese))
[20]	Evers KU, Ziemer G. Model tests with a compliant cylindrical structure to investigate ice-induced vibrations. Journal of Offshore Mechanics and Arctic Engineering, 2016,138(4):041501
[21]	Ziemer G, Hinse P. Relation of maximum structural velocity and ice drift speed during frequency lock-in//Port and Ocean Engineering under Arctic Conditions, Busan. Korea, 2017, 1-12
[22]	Hendrikse H, Ziemer G, Owen CC. Experimental validation of a model for prediction of dynamic ice-structure interaction. Cold Regions Science and Technology, 2018,151:345-358
[23]	Owen CC. Ice-induced vibrations of vertically sided model structures: Comparison of structures with circular and rectangular cross-section subjected to the frequency lock-in regime. [PhD Thesis]. Delft: Delft University of Technology, 2017
[24]	Matlock H, Dawkins W, Panak J. A model for the prediction of ice structure interaction. Journal of Engineering Mechanics, 1969,4:1083-1092
[25]	Sodhi DS. Vertical penetration of floating ice sheets. International Journal of Solids & Structures, 1998,35(31-32):4275-4294
[26]	Huang G, Liu P. A dynamic model for ice-induced vibration of structures. Journal of Offshore Mechanics and Arctic Engineering, 2009,131(1):6
[27]	Blenkarn KA. Measurement and analysis of ice forces on Cook Inlet Structures//Proc. 2nd OTC Conf, Houston, TX, OTC 1261, 1970,2:365-378
[28]	M??tt?nen M. On conditions for the rise of self-excited ice-induced autonomous oscillations in slender marine structures. Finnish-Swedish Winter Navigation Board, Finland, Research Report 25, 1978,98
[29]	M??tt?nen M. Ice-induced vibrations in structures-self-excitation// IAHR 1988, University of Hokkaido, Sapporo, Japan, 1988,2:658-665
[30]	Yue Q, Guo F, Krn T. Dynamic ice forces of slender vertical structures due to ice crushing. Cold Regions Science and Technology, 2009,56(2-3):77-83
[31]	Wang Q. Ice-induced vibrations under continuous brittle crushing for an offshore wind turbine. [PhD Thesis]. Trondheim: Norwegian University of Science and Technology, 2015
[32]	叶柯华, 李春, 杨阳, 等. 基于自激冰振的风力机海冰载荷分析. 振动与冲击, 2017,24:27 (Ye Kehua, Li Chun, Yang Yang, et al. Sea-ice load analysis of offshore wind turbines based on self-excited ice induced vibration. Journal of Vibration and Shock, 2017,24:27(in Chinese))
[33]	Heinonen J, Rissanen S. Coupled-crushing analysis of a sea ice-wind turbine interaction -- feasibility study of FAST simulation software. Ships & Offshore Structures, 2017,12(7-8):1-8
[34]	Shi W, Tan X, Gao Z, et al. Numerical study of ice-induced loads and responses of a monopile-type offshore wind turbine in parked and operating conditions. Cold Regions Science and Technology, 2016,123:121-139
[35]	Ji X, Oterkus E. Physical mechanism of ice-structure interaction. Journal of Glaciology, 2018: 1-11
[36]	Ji X, Oterkus E. A new van der Pol equation based ice-structure interaction model for ice-induced vibrations// 6th International Conference of Marine Structures (MARSTRUCT), 2017, 107-112
[37]	Hendrikse H, Nord TS. Dynamic response of an offshore structure interacting with an ice floe failing in crushing. Marine Structures, 2019,65(5):271-290
[38]	Seidel M, Hendrikse H. Analytical assessment of sea ice-induced frequency lock-in for offshore wind turbine monopiles. Marine Structures, 2018,60:87-100
[39]	Hendrikse H, Seidel M, Metrikine A, et al. Initial results of a study into the estimation of the development of frequency lock-in for offshore structures subjected to ice loading// International Conference on Port & Ocean Engineering Under Arctic Conditions, 2017
[40]	Dostal L, Lourens EM, Metrikine A, et al. Nonlinear model parameter identification for ice-induced vibrations// Procedia Engineering, 2017, 583-588
[41]	Nord TS, Ole ?iseth , Lourens EM. Ice force identification on the Nordstr?msgrund lighthouse. Computers & Structures, 2016,169:24-39
[42]	Hendrikse H, Metrikine A. Interpretation and prediction of ice induced vibrations based on contact area variation. International Journal of Solids & Structures, 2015, 75-76:336-348
[43]	Van d MP, Lourens E. Operational vibration-based response estimation for offshore wind lattice structures. Structural Health Monitoring and Damage Detection, 2015,7:83-96
[44]	Qu Y. A new method for the analysis of ice intermittent crushing induced lock-in vibration// Proceedings of the Twenty Third International Offshore and Polar Engineering Conference, Anchorage, Alaska, 2013
[45]	K?rn? T. Finite ice f?ilure depth in penetration of a vertical indentor into an ice edge. Annak of Glaciology, 1994,19:114-120
[46]	Gagnon RE. An explanation for the Molikpaq May 12,1986 event. Cold Regions Science and Technology, 2012,82(10):75-93
[47]	Kuiper GL. Correlation curves for brittle and ductile ice failure based on full-scale data. Port and Ocean Engineering under Arctic Conditions, 2013, 13-31