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| Centrifuge tests of ship impact on pile groups beneath offshore wind turbines |
Ling-gang KONG1,2( ),Jia YU1,2,Yun-min CHEN1,2 |
1. Institute of Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China
2. Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education, Zhejiang University, Hangzhou 310058, China |
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Abstract An onboard system was built to simulate ship impact on the pile group foundation of offshore wind turbines. Four centrifugal model tests on a 2×2 pile group were conducted in saturated dense sand, including the tests on pile groups with and without an upper wind turbine subjected to lateral impact or eccentric impact with an eccentricity of 4.5 times pile diameters. The influence of the exist of wind turbine on top of pile cap and the impacted position by ship on pile cap on the impact force and the dynamic response of pile groups was investigated. Data from the model tests showed that strong dynamic interaction existed between the wind turbine and its underlying pile group. The motion of the pile cap made the wind turbine cause both lateral and torsional vibrations. The wind turbine shared and dissipated part of the energy transferred from the ship, which made the acceleration amplitudes of the pile cap attenuate quickly in the free vibration phase. In addition, the impact position on pile cap significantly affected the impact force and the internal forces of the group piles. The measured peak impact force from the test on the pile group without wind turbine subjected to eccentric impact was 20% smaller than that from the test on the pile group subjected to lateral impact, and the impact velocity in the former test was 26% higher than that in the latter. The maximum ratio of the peak pile-head bending moments of the piles was 3.2 in the test on the pile group without wind turbine subjected to eccentric impact. Generally, comparing with lateral impact on pile cap by ship, eccentric impact is more critical to make a pile group fail.
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Received: 21 August 2021
Published: 28 February 2023
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| Fund: 国家自然科学基金资助项目(51579218).; 国家自然科学基金基础科学中心资助项目(51988101) |
船舶撞击近海风机群桩基础的离心模型试验
建立船舶撞击近海风机群桩基础的离心模拟系统. 在饱和密砂中开展了4组2×2群桩的撞击试验，包括水平撞击和撞击点距承台中心4.5倍桩径的水平偏心撞击群桩基础试验以及水平撞击和水平偏心撞击装有上部风机的群桩基础试验. 重点考察承台上部风机存在与否以及船舶撞击位置对船舶撞击力和群桩基础动力响应的影响. 试验结果表明，风机与群桩基础之间存在明显动力相互作用.承台的振动带动风机发生水平摆动和扭转振动；风机分担和消耗一部分经船舶撞击传递给群桩基础的能量，导致在自由振动阶段承台的振幅快速衰减.撞击承台的位置对撞击力和群桩内力有明显影响.对比水平和水平偏心撞击群桩试验，虽然偏心撞击工况下的撞击速度比水平撞击工况下的大26% ，但偏心撞击的撞击力峰值比水平撞击的小20 %；在群桩受偏心撞击工况下各基桩桩头弯矩峰值相差最大达3.2倍.偏心撞击更易引发群桩破坏.
关键词：
群桩,
近海风机,
水平偏心撞击,
动力响应,
离心试验
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| [1] |
KONG L G, CHEN R P, WANG S H, et al Response of 3×3 pile groups in silt subjected to eccentric lateral loading[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2015, 141 (7): 04015029
doi: 10.1061/(ASCE)GT.1943-5606.0001313
|
|
|
| [2] |
KONG L G, FAN J Y, LIU J W, et al Group effect in piles under eccentric lateral loading in sand[J]. Journal of Zhejiang University-Science A: Applied Physics and Engineering, 2019, 20: 243- 257
|
|
|
| [3] |
KONG L G, ZHANG Z C, CHEN Y M Nonlinear analysis of pile groups subjected to combined lateral and torsional loading[J]. Journal of Zhejiang University-Science A: Applied Physics and Engineering, 2020, 21 (3): 179- 192
|
|
|
| [4] |
GU M, KONG L G, CHEN R P, et al Response of 1×2 pile group under eccentric lateral loading[J]. Computers and Geotechnics, 2014, 57: 114- 121
doi: 10.1016/j.compgeo.2014.01.007
|
|
|
| [5] |
孔令刚, 顾明, 陈仁朋, 等 偏心距对水平受荷双桩基础响应影响[J]. 岩石力学与工程学报, 2013, 32 (Suppl.2): 4174- 4182
KONG Ling-gang, GU Ming, CHEN Ren-peng, et al Influence of eccentricity on two-pile foundation subjected to lateral loading[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32 (Suppl.2): 4174- 4182
|
|
|
| [6] |
顾明. 水平循环及偏心荷载作用下群桩性状模型试验研究 [D]. 杭州: 浙江大学, 2014.
GU Ming. Model test study on behavior of pile group subjected to lateral cyclic and eccentric loads [D]. Hangzhou: Zhejiang University, 2014.
|
|
|
| [7] |
CONSOLAZIO G R, COOK R A, MCVAY M C, et al. Barge impact testing of the St. George Island Causeway Bridge: final report: physical testing and data interpretation [M]. Gainesville: University of Florida, 2006.
|
|
|
| [8] |
CHU L M, ZHANG L M Centrifuge modeling of ship impact loads on bridge pile foundations[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2011, 137 (4): 405- 420
doi: 10.1061/(ASCE)GT.1943-5606.0000446
|
|
|
| [9] |
CAI S W. Centrifuge modeling of system performance of bridge foundations in inland waterways subject to vessel collision [D]. Hong Kong: Hong Kong University of Science and Technology, 2010.
|
|
|
| [10] |
肖方初. 考虑船舶撞击位置和方向的群桩动力响应离心试验研究 [D]. 杭州: 浙江大学, 2019.
XIAO Fang-chu. Centrifuge model tests of ship impact on a pile group at different positions and directions [D]. Hangzhou: Zhejiang University, 2019.
|
|
|
| [11] |
EMAMI AZADI M R, NORDAL S, SADEIN M Nonlinear behavior of pile-soil subjected to torsion due to environmental loads on jacket type platforms[J]. WSEAS Transactions on Fluid Mechanics, 2008, 3 (4): 390- 400
|
|
|
| [12] |
陈云敏, 韩超, 凌道盛, 等 ZJU400离心机研制及其振动台性能评价[J]. 岩土工程学报, 2011, (12): 1887- 1894
CHEN Yun-min, HAN Chao, LING Dao-sheng, et al Development of geotechnical centrifuge ZJU400 and performance assessment of its shaking table system[J]. Chinese Journal of Geotrechnical Engineering, 2011, (12): 1887- 1894
|
|
|
| [13] |
KONG L G, ZHANG L M Rate-controlled lateral-load pile tests using a robotic manipulator in centrifuge[J]. Geotechnical Testing Journal, 2007, 30 (3): 192- 201
|
|
|
| [14] |
YANG D, NAESGAARD E, BYRNE P, et al Numerical model verification and calibration of George Massey Tunnel using centrifuge models[J]. Canadian Geotechnical Journal, 2004, 41: 921- 942
doi: 10.1139/t04-039
|
|
|
| [15] |
凌道盛, 郭恒, 蔡武军, 等 地铁车站地震破坏离心机振动台模型试验研究[J]. 浙江大学学报: 工学版, 2012, 46 (12): 2201- 2209
LING Dao-sheng, GUO Heng, CAI Wu-jun, et al Research on seismic damage of metro station with centrifuge shaking table model test[J]. Journal of Zhejiang University: Engineering Science, 2012, 46 (12): 2201- 2209
|
|
|
| [16] |
BOLTON M D The strength and dilatancy of sands[J]. Géotechnique, 1986, 36: 65- 78
|
|
|
| [17] |
BOLTON M D, GUI M W, GARNIER J, et al Centrifuge cone penetration tests in sand[J]. Géotechnique, 1999, 49 (4): 543- 552
|
|
|
| [18] |
CRAIG W H, SABAGH S K Stress-level effects in model tests on piles[J]. Canadian Geotechnical Journal, 1994, 31 (1): 28- 41
doi: 10.1139/t94-004
|
|
|
| [19] |
GRUNDHOFF T, LATOTZKE J, LAUE J. Investigations of vertical piles under horizontal impact [C]// Centrifuge 98. Rotterdam: Balkema, 1998: 569-574.
|
|
|
| [20] |
MASOUD H B, JEAN L C, FAVRAUD C, et al An electromagnetic horizontal impact device for centrifuge testing[J]. International Journal of Physical Modelling in Geotechnics, 2007, 7 (1): 1- 11
doi: 10.1680/ijpmg.2007.070101
|
|
|
| [21] |
KONG L G, ZHANG L M Centrifuge modeling of torsionally loaded pile groups[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2007, 133 (11): 1374- 1384
|
|
|
| [22] |
AASHTO. Guide specifications and commentary for vessel collision design of highway bridges: GVCB-2009 [S]. Washington: American Association of State Highway and Transportation Officials, 2009.
|
|
|
| [23] |
CEN. Eurocode 1-actions on structures-part 1-7: general actions-accidental actions: EN1991-1-7 [S]. Brussels: European Committee for Standardization, 2006: 53.
|
|
|
| [24] |
铁道第三勘察设计院. 铁路桥涵设计基本规范: TB 1002.1-2005 [S]. 北京: 中国铁道出版社, 2005: 30-31.
|
|
|
| [25] |
BISHOP A W, ELDIN G Undrained triaxial tests on saturated sands and their significance in the general theory of shear strength[J]. Géotechnique, 1950, 2 (1): 13- 32
|
|
|
| [26] |
黄博, 汪清静, 凌道盛, 等 饱和砂土三轴试验中反压设置与抗剪强度的研究[J]. 岩土工程学报, 2012, 34 (7): 1313- 1319
HUANG Bo, WANG Qing-jing, LING Dao-sheng, et al Effects of back pressure on shear strength of saturated sand in triaxial tests[J]. Chinese Journal of Geotechnical Engineering, 2012, 34 (7): 1313- 1319
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