本文選題：多塔斜拉橋 + 拉索�。� 參考：《長安大學》2015年碩士論文

【摘要】：斜拉橋因其美觀的造型和較強的跨越能力,成為倍受現代設計師們青睞的一種橋型。作為斜拉橋關鍵部件的斜拉索,具有質量小,阻尼低和柔度大的特點,在風荷載、車輛荷載等作用下斜拉索容易發(fā)生大幅度的振動。拉索的振動容易加速拉索的疲勞,最終導致拉索的破壞,直接影響橋梁的使用安全。因此,對斜拉索振動特性的研究已經成為斜拉橋設計的一個重要環(huán)節(jié)。由于多塔斜拉橋剛度不足,自身容易發(fā)生振動現象,同時也易導致拉索的共振,所以如何提高多塔斜拉橋剛度已經成為當今橋梁建設領域的熱議話題之一。為了研究多塔斜拉橋剛度對拉索振動的影響程度,本文首先建立了不同主梁剛度、橋塔剛度的有限元模型,討論剛度對于成橋動力特性的影響。接著在建立了三維空間內的拉索面內-外-橋面耦合振動模型,得到了拉索面內-外-橋面耦合振動方程組,采用多尺度法分析了拉索面內-外-橋面耦合振動特性。最后,通過計算邊塔拉索的面內外固有頻率,與不同工況成橋的頻率進行對比,分析可能發(fā)生大幅共振的拉索以及其面內外的振動特性。結果表明,多塔斜拉橋主梁剛度對于拉索發(fā)生面內外共振的可能都有一定的影響,對面內共振振幅影響大,而橋塔的剛度則對共振幅值影響很小,成橋的整體剛度則對拉索振動發(fā)生的可能影響強烈。
[Abstract]:Because of its beautiful shape and strong span ability, cable-stayed bridge has become a bridge type favored by modern designers. As a key component of a cable-stayed bridge, the cable has the characteristics of low mass, low damping and large flexibility. Under the action of wind load and vehicle load, the cable-stayed cable is easy to vibrate in a large amplitude. The vibration of cable accelerates the fatigue of the cable and leads to the damage of the cable, which directly affects the safety of the bridge. Therefore, the study of cable vibration characteristics has become an important link in the design of cable-stayed bridge. Due to the lack of stiffness of multi-tower cable-stayed bridge, it is easy to vibrate itself and lead to the resonance of cable, so how to improve the stiffness of multi-tower cable-stayed bridge has become one of the hot topics in the field of bridge construction. In order to study the influence of multi-tower cable-stayed bridge stiffness on cable vibration, the finite element model of different main beam stiffness and bridge tower stiffness is established in this paper, and the influence of stiffness on the dynamic characteristics of the bridge is discussed. Then, the coupling vibration model of cable plane and external bridge deck in three dimensional space is established, and the coupling vibration equations between cable plane and external bridge deck are obtained. The coupling vibration characteristics of cable plane and external bridge deck are analyzed by using multi-scale method. Finally, by calculating the natural frequencies in and out of plane and comparing with the frequencies of the bridge under different working conditions, the vibration characteristics of the cables which may have large resonance and the vibration inside and outside the plane are analyzed. The results show that the stiffness of the main girder of the multi-tower cable-stayed bridge may have a certain effect on the in-plane resonance of the cable, and the amplitude of the resonance on the opposite side has a great effect, while the stiffness of the tower has little effect on the co-amplitude. The overall stiffness of the bridge may have a strong effect on the vibration of the cable.
【學位授予單位】：長安大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U448.27

【參考文獻】

相關期刊論文 前1條

1 喻梅;李喬;廖海黎;;多塔斜拉橋的剛度配置[J];四川建筑科學研究;2010年04期

，

本文編號：1921258