【摘要】：鋼混疊合梁橋主梁為開口斷面。因具有均勻合理的受力特性、造價(jià)低及施工方便等優(yōu)勢，在結(jié)構(gòu)抗扭剛度相對(duì)較大的斜拉橋中有越來越多的應(yīng)用。但疊合梁懸索橋由于抗扭剛度的降低，導(dǎo)致其顫振臨界風(fēng)速顯著降低，并且在較低的風(fēng)速下很容易出現(xiàn)渦激共振現(xiàn)象。為了發(fā)揮出疊合梁懸索橋的優(yōu)勢，提高抗風(fēng)穩(wěn)定性，因此就有必要對(duì)疊合梁懸索橋的渦激振動(dòng)與顫振特性進(jìn)行研究。本文以在建的主跨838m的宜昌廟嘴長江大橋的主梁形式為基礎(chǔ)，通過節(jié)段模型風(fēng)洞試驗(yàn)及理論分析，研究疊合梁懸索橋渦激振動(dòng)和顫振特性，主要工作包括以下幾個(gè)方面： (1)詳細(xì)綜述了橋梁的風(fēng)致振動(dòng)的基本概念和基本理論，以及橋梁氣動(dòng)性能的影響因素和氣動(dòng)措施，在參考相似橋梁相關(guān)研究的基礎(chǔ)上提出了本文所要研究的主要內(nèi)容。 (2)研究了在主梁不同位置設(shè)置穩(wěn)定板對(duì)疊合梁渦激振動(dòng)和顫振穩(wěn)定性的影響。本文共設(shè)計(jì)了5組穩(wěn)定板典型位置的對(duì)比試驗(yàn)，通過對(duì)5組試驗(yàn)數(shù)據(jù)的分析對(duì)比發(fā)現(xiàn)，不同位置的穩(wěn)定板對(duì)疊合梁懸索橋渦激振動(dòng)影響不同，特別是對(duì)扭轉(zhuǎn)振動(dòng)影響較大；在主梁設(shè)置兩道下穩(wěn)定板能顯著改善其渦振性能。增加穩(wěn)定板后斷面的顫振穩(wěn)定性也顯著提高。 (3)利用基于有限元的三維顫振分析方法對(duì)疊合梁懸索橋進(jìn)行顫振穩(wěn)定性分析，預(yù)測了復(fù)模態(tài)頻率及阻尼隨風(fēng)速的變化，并基于復(fù)特征值攝動(dòng)理論首次對(duì)三維顫振分析中出現(xiàn)的特征值的變化做出定量理論解釋。分析表明，①基于顫振導(dǎo)數(shù)得到的顫振臨界風(fēng)速比主梁節(jié)段模型風(fēng)洞試驗(yàn)值略大，，可能是由于顫振判據(jù)差異引起的；②顫振分析中出現(xiàn)的扭轉(zhuǎn)振動(dòng)頻率下降現(xiàn)象是氣動(dòng)剛度和非經(jīng)典的氣動(dòng)阻尼共同作用的結(jié)果。 (4)分析比較了3種渦激力經(jīng)驗(yàn)?zāi)Ｐ偷膮?shù)識(shí)別方法及渦激力形式。利用節(jié)段模型渦激振動(dòng)風(fēng)洞試驗(yàn)得到的試驗(yàn)數(shù)據(jù)，對(duì)渦激力氣動(dòng)參數(shù)進(jìn)行識(shí)別。研究發(fā)現(xiàn)，在同一風(fēng)速下不同渦激力模型識(shí)別的渦激力幅值相同；利用識(shí)別的渦激力反算渦激響應(yīng)能滿足識(shí)別精度。
[Abstract]:The main beam of steel hybrid bridge is an open section. Due to the advantages of uniform and reasonable mechanical characteristics, low cost and convenient construction, the cable-stayed bridges with relatively large torsional stiffness are more and more used in cable-stayed bridges. However, due to the reduction of torsional stiffness, the critical flutter velocity of superimposed suspension bridge decreases significantly, and vortex-induced resonance is easy to occur at lower wind speed. In order to give full play to the advantages of superimposed beam suspension bridges and improve wind stability, it is necessary to study the vortex-induced vibration and flutter characteristics of superimposed beam suspension bridges. Based on the main beam form of the Yichang Miaozui Yangtze River Bridge with a main span of 838m under construction, the vortex-induced vibration and flutter characteristics of the superimposed beam suspension bridge are studied by the segmental model wind tunnel test and theoretical analysis. The main work includes the following aspects: (1) the basic concepts and theories of wind-induced vibration of bridges are summarized in detail, as well as the influencing factors and aerodynamic measures of bridge aerodynamic performance. The main contents of this paper are put forward on the basis of reference to the related research of similar bridges. (2) the effects of stability plates at different positions on vortex-induced vibration and flutter stability of laminated beams are studied. Through the analysis and comparison of five groups of test data, it is found that the vortex-induced vibration of superimposed beam suspension bridge is affected by the stability plate at different positions, especially on the torsional vibration of the suspension bridge with superimposed beams. The results show that the stability plate at different positions has different effects on the vortex-induced vibration of superimposed beam suspension bridges, especially on the torsional vibration of suspension bridges. The vortex vibration performance of the main beam can be significantly improved by setting two stable plates under the main beam. The flutter stability of the rear section of the plate is also improved significantly. (3) the three-dimensional flutter analysis method based on finite element method is used to analyze the flutter stability of superimposed beam suspension bridge, and the variation of complex modal frequency and damping with wind speed is predicted. Based on the perturbation theory of complex eigenvalues, the variation of eigenvalues in three-dimensional flutter analysis is explained quantitatively for the first time. The results show that (1) the flutter critical wind speed based on flutter derivative is slightly larger than the wind tunnel test value of the main beam segment model, which may be due to the difference of flutter criterion; (2) the frequency drop phenomenon of torsional vibration in flutter analysis is caused by the combination of aerodynamic stiffness and non-classical aerodynamic damping. (4) the parameter identification methods and vortex force forms of three kinds of empirical models of vortex excitation are analyzed and compared. The aerodynamic parameters of vortex-induced force are identified by using the wind tunnel test data of segment model vortex-induced vibration. It is found that the amplitude of vortex excitation force identified by different vortex excitation models under the same wind speed is the same, and the identification accuracy can be satisfied by calculating the vortex excitation response by using the identified vortex excitation force.
【學(xué)位授予單位】：湖南大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U448.25;U441.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 朱樂東;橋梁渦激共振試驗(yàn)節(jié)段模型質(zhì)量系統(tǒng)模擬與振幅修正方法[J];工程力學(xué);2005年05期

2 陳政清;胡建華;;橋梁顫振導(dǎo)數(shù)識(shí)別的時(shí)域法與頻域法對(duì)比研究[J];工程力學(xué);2005年06期

3 金挺;林志興;;扁平箱形橋梁斷面斯特羅哈數(shù)的雷諾數(shù)效應(yīng)研究[J];工程力學(xué);2006年10期

4 鮮榮;廖海黎;朱超;盛建軍;;Larsen廣義渦激振動(dòng)模型在大跨度橋梁抗風(fēng)設(shè)計(jì)中的應(yīng)用[J];公路;2010年02期

5 張志田;卿前志;肖瑋;陳政清;;開口截面斜拉橋渦激共振風(fēng)洞試驗(yàn)及減振措施研究[J];湖南大學(xué)學(xué)報(bào)(自然科學(xué)版);2011年07期

6 李明水，賀德馨;鈍體渦激力參數(shù)的識(shí)別[J];空氣動(dòng)力學(xué)學(xué)報(bào);1995年04期

7 謝霽明 ,項(xiàng)海帆;橋梁三維顫振分析的狀態(tài)空間法[J];同濟(jì)大學(xué)學(xué)報(bào);1985年03期

8 宋錦忠,林志興,徐建英;橋梁抗風(fēng)氣動(dòng)措施的研究及應(yīng)用[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);2002年05期

9 楊?yuàn)`昕;葛耀君;項(xiàng)海帆;;中央穩(wěn)定板顫振控制效果和機(jī)理研究[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);2007年02期

10 張偉;魏志剛;楊?yuàn)`昕;葛耀君;;基于高低雷諾數(shù)試驗(yàn)的分離雙箱渦振性能對(duì)比[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);2008年01期

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