冲刷深度对简支桥模态参数影响的模型试验

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振动与冲击 ›› 2016, Vol. 35 ›› Issue (14) : 145-150.

论文

冲刷深度对简支桥模态参数影响的模型试验

梁发云 1, 2 ，王琛 1, 2 ，贾承岳 1, 2 ，王玉 1, 2

作者信息 +

Test of the Influence of Scour Depth on Modal Parameters of Simple-Supported Bridge

LIANG Fayun 1,2 WANG Chen1,2 JIA Chenyue 1,2 WANG Yu1,2

Author information +

文章历史 +

摘要

大多数的桥梁损毁是由于桥梁基础受到冲刷，使桥墩埋深减小，降低了桥墩基础的承载能力所致。对于桥梁基础冲刷深度的直接量测比较困难，而在简支桥的桥墩系统中，桥桩基础的裸露程度直接影响到桥墩系统的整体刚度，进而影响系统的模态频率。基于该测试原理，采用瞬时激励的方式，通过三跨简支桥动力模型试验，研究简支桥桩基础的冲刷深度与其动力特性，揭示简支桥中同跨下两墩不均匀冲刷时简支桥振动特性的变化规律。试验研究表明，易受冲刷影响的是扭转弯曲模态和侧向弯曲模态，这两个模态频率值随着冲刷深度的增加而逐渐减小，且侧向弯曲模态（低频模态）频率值降低相对较快，扭转弯曲模态（高频模态）频率值降低相对较慢；当简支桥同跨下两墩受到不同程度冲刷时，桥墩冲刷程度可以采用峰值频率的幅值变化进行判断，越靠近冲刷程度更严重的桥墩测点，测得的模态频率值相同，但是频率值对应的幅值却有着明显差别，可以作为判断桥墩冲刷程度的重要依据。

Abstract

Many failures of bridges are caused by scour around the foundation，which enlarges the scour depth and reduce the bearing capacity of the piers. However, the monitoring of the scour is difficult according to practical experience. In the system of simple supported bridge，the scour depth also has its influence on the stiffness and modal parameters of the bridges. Based on the theory of modal parameters and test of a simple supported bridge, the relationship between depth and dynamic characteristics and the regularity of the bridge are discussed with instant impulse. In conclusion, the torsional and lateral bending modes are vulnerable to the scour, and both of them decreases with the increase of scour depth. The lateral bending mode (low-frequency mode) decreases faster than the torsional mode (high-frequency mode). When the scours around two piers are different, they can be judged by the amplitude of the peak frequency. The scour process can be detected by the analysis according to the modal modes and its amplitude.

导出引用

梁发云 1, 2,王琛 1, 2,贾承岳 1, 2,王玉 1, 2. 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 1,2 WANG Chen1,2 JIA Chenyue 1,2 WANG Yu1,2. Test of the Influence of Scour Depth on Modal Parameters of Simple-Supported Bridge[J]. Journal of Vibration and Shock, 2016, 35(14): 145-150

参考文献

[1] Lagasse PF, Clopper PE, Zevenbergen LW, et al. NCHRP Report 593: Countermeasures to protect bridge piers from scour [R]. Transportation Research Board, Washington DC, USA, 2007.
[2] Wardhana K, Hadipriono FC. Analysis of recent bridge failures in the United States [J]. Journal of Performance of Constructed Facilities, ASCE, 2003, 17(3): 144-150.
[3] 中华人民共和国行业标准. 公路工程水文勘测设计规范(JTG C30-2002) [S]. 中华人民共和国交通部, 2002.
National Standard of the People’s Republic of China. Hydrological Specifications for Survey and Design of Highway Engineering (JTG C30-2002) [S]. Ministry of Communication of People’s Republic of China.
[4] Melville BW, Coleman SE. Bridge Scour [M]. Water Resources Publications, Colorado, USA, 2000.
[5] Liang FY, Bennett CR, Parsons RL, et al. A literature review on behavior of scoured piles under bridges [C]. In: the 2009 International Foundation Congress and Equipment Expo, Orlando, GSP186, ASCE, 2009:482-489.
[6] Shaji T, Somayaji S, Mathews MS. Ultrasonic pulse velocity technique for inspection and evaluation of timber [J]. Journal of materials in civil engineering, 2000, 12(2): 180-185.
[7] Douglas RA, Holt JD. Determining length of installed timber pilings by dispersive wave propagation methods [R]. Center for Transportation Engineering Studies, North Carolina State University, 1993.
[8] Lo KF, Ni SH, Huang YH, et al. Measurement of unknown bridge foundation depth by parallel seismic method [J]. Experimental Techniques, 2009, 33(1): 23-27.
[9] Watanabe S, Samizo M, Fuchiwaki A, et al. Evaluation of the Structural Integrity of Bridge Pier Foundations under Flood Condition by the Natural Frequencies Measured with a Micro-tremor [J]. RTRI Report, 2007, 21(1): 31-36.
[10] Ko YY, Lee WF, Chang WK. Scour evaluation of bridge foundations using vibration measurement [C]. International Conference on Scour and Erosion 2010: 884-893.
[11] 张达德, 陈柏麟, 黄钢. 冲刷桥墩基础的HHT振动频谱特性分析与判读研究[J]. 岩土力学, 2010, 31(7): 2241-2246.
Zhang Da-de, Chen Bo-lin, Huang Gang. Characteristics analysis and judgment of vibrating frequency for scoured pier foundation by Hilbert Huang transfotm [J]. Rock and Soil Mechanics, 2010, 31 (7): 2241-2246. (in Chinese)
[12] 梁发云, 李彦初, 陈海兵. 冲刷作用下单桩循环加载特性的模型试验[J]. 同济大学学报, 2014, 42(10): 1511-1515
Liang Fa-yun, Li Yan-chu, Chen Hai-bing. Influence of scour depth on vertically cyclic behaviors of singe pile with model tests [J]. Journal of Tongji University, 2014, 42(10):1511-1515
[13] 贾承岳, 梁发云, 王玉. 冲刷深度对单桩自振频率影响的试验分析初探[J]. 结构工程师，2013,29(1): 114-117.
Jia Cheng-yue, Liang Fa-yun, Wang Yu. A preliminary Investigation on the Influences of Scour Depth on Natural Frequencies of a Single Pile [J]. Structural Engineering, 2013,29(1): 114-117.
[14] 王玉, 贾承岳, 梁发云, 姚笑青. 桥墩不均匀冲刷对简支桥模态影响的数值模拟. 岩土工程学报, 2013, 35(Sup.2): 779-782.
Wang Yu, Jia Cheng-yue, Liang Fa-yun, Yao Xiao-qing. Numerical simulation of influence of non-uniform scour depth on modes of simply supported bridge [J]. Chinese Journal of Geotechnical Engineering, 2013, 35(Sup.2): 779-782.
[15] 姚锦宝, 夏禾, 战家旺. 铁路桥梁基础受冲刷对桥墩模态特性的影响分析[J]. 中国铁道科学, 2008, 29(1): 31-35.
Yao Jin-bao, Xia He, Zhan Jia-wang. Analysis on the Influence of the Bridge Foundation under Scouring on the Natural Vibration Characteristics of Piers [J]. China Railway Science, 2008,29(1):31–35.
[16] 卢中一, 高正荣, 吴丽华, 等. 南京长江三桥桥墩基础的局部冲刷[J]. 人民长江, 2005, 36(10): 48-50.
LU Zhongyi, GAO Zhengrong, WU Lihua, and et al. Local scour at pier foundation of Nanjing Yangtze 3rd bridge [J]. Wuhan: Yangtze River, 2005, 36(10): 48-50.
[17] 伍冬领, 邢艳, 谢晓波, 等. 钱江四桥桥墩局部冲刷试验研究[J]. 桥梁建设, 2005, (2): 19-21.
WU Donglin, XING Yan, XIE Xiaobo, and et al. Experimental study of local scour at piers of the Qianjiang 4th bridge [J]. Wuhan: bridge construction, 2005, (2): 19-21..