本文選題：拉索 + 輔助索�。� 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：斜拉索作為斜拉橋的主要組成部分,其作用主要是將橋主梁和各種外部荷載傳至橋塔上。由于斜拉索的質(zhì)量比較小、而柔度比較大,因此很容易在風(fēng)、雨、橋塔振動(dòng)等外部激勵(lì)作用下產(chǎn)生大幅振動(dòng),會(huì)引起拉索錨固端產(chǎn)生裂縫,破壞其表面的防腐材料,減少拉索的使用壽命,以及引起行車(chē)、行人的不安。工程中通常采用安裝阻尼器、改變拉索表面形狀的氣動(dòng)措施、安裝輔助索等措施來(lái)抑制拉索的振動(dòng)。氣動(dòng)措施減震機(jī)理非常復(fù)雜,并且針對(duì)外部的激勵(lì)也比較單一,阻尼器則會(huì)受到斜拉索跨度增大的限制,而輔助索將各獨(dú)立的拉索連接成索網(wǎng)結(jié)構(gòu),減少了拉索的有效長(zhǎng)度,使各拉索的振動(dòng)互相牽制耦合,顯著提高索網(wǎng)系統(tǒng)的固有振動(dòng)頻率。但是輔助索減震的機(jī)理尚未清楚,優(yōu)化方法尚未建立,輔助索減震有待進(jìn)一步的研究。基于兩個(gè)條件:(1)拉索振動(dòng)幅度不大,輔助索一直處于張緊狀態(tài)不會(huì)出現(xiàn)松弛情況(2)輔助索尺寸較小,忽略其振動(dòng)對(duì)拉索振動(dòng)的影響,則輔助索對(duì)拉索來(lái)說(shuō)相當(dāng)于一彈性的橫向連接。本課題對(duì)接橋面輔助索-索網(wǎng)結(jié)構(gòu)的微幅振動(dòng)展開(kāi)理論與試驗(yàn)研究,忽略輔助索振動(dòng)對(duì)斜拉索振動(dòng)的影響,鑒于索網(wǎng)結(jié)構(gòu)的復(fù)雜性,本文建立了雙拉索附加橫向連接的簡(jiǎn)化索網(wǎng)結(jié)構(gòu)和系統(tǒng)結(jié)構(gòu)微分方程,對(duì)橫向連接的剛度進(jìn)行剛度無(wú)窮大和零的極限參數(shù)分析,以及橫向連接的剛度在零到無(wú)窮大之間的非極限參數(shù)分析。主要研究了拉索長(zhǎng)度比、橫向連接的位置比、拉索頻率比、拉索質(zhì)量-張力比四個(gè)參數(shù)對(duì)前四階系統(tǒng)面內(nèi)自由振動(dòng)頻率的影響,以及參數(shù)之間的相互影響作用。針對(duì)理論分析結(jié)果,本文進(jìn)行了雙拉索系統(tǒng)結(jié)構(gòu)模型試驗(yàn)。首先進(jìn)行單索試驗(yàn)測(cè)試其面內(nèi)外前二階頻率和阻尼比,其次在0.2L、0.4L位置安裝形狀記憶合金、尼龍線(xiàn)兩種材料的橫向連接,測(cè)試系統(tǒng)的面內(nèi)外前二階頻率和阻尼比。發(fā)現(xiàn)附加橫向連接的系統(tǒng)面內(nèi)自由振動(dòng)頻率要明顯高于單索的振動(dòng)頻率。對(duì)每一種工況進(jìn)行面內(nèi)自由振動(dòng)理論計(jì)算,并與試驗(yàn)結(jié)果進(jìn)行對(duì)比發(fā)現(xiàn)分析誤差都小于5%,驗(yàn)證了理論分析模型及方程的準(zhǔn)確性。對(duì)于該類(lèi)拉索-橫向連接系統(tǒng)的研究有一定的指導(dǎo)意義與實(shí)用價(jià)值。
[Abstract]:As the main component of the cable-stayed bridge, the cable-stayed cable is mainly used to transfer the main beam and various external loads to the tower. Because the mass of stay cable is small and flexibility is high, it is easy to produce large vibration under external excitation such as wind, rain and tower vibration, which will cause cracks at the anchor end of cable and destroy the anticorrosive material on its surface. Reduce the service life of lasso, and cause trouble for driving and pedestrians. In order to restrain the vibration of the cable, the damper is usually installed, the surface shape of the cable is changed and the auxiliary cable is installed. The damping mechanism of aerodynamic measures is very complicated, and the external excitation is relatively simple, and the damper will be limited by the increase of the span of the stay cable, and the auxiliary cable will connect each independent cable to the cable-netted structure, thus reducing the effective length of the cable. The vibration of each cable is pinched and coupled with each other, and the natural vibration frequency of the cable net system is improved significantly. However, the mechanism of auxiliary cable damping is not clear, the optimization method has not been established, and the auxiliary cable damping needs further study. Based on two conditions: (1) the vibration amplitude of the cable is not large, the auxiliary cable will not be relaxed in the state of tension all the time. (2) the size of the auxiliary cable is small, and the effect of the vibration on the vibration of the cable is ignored. The auxiliary cable is equivalent to an elastic transverse connection to the cable. In this paper, the theoretical and experimental research on the micro-amplitude vibration of the cable-cable net structure supported by the bridge deck is carried out, and the influence of the auxiliary cable vibration on the cable-stayed vibration is ignored. In view of the complexity of the cable-net structure, In this paper, the differential equations of simplified cable-net structures and system structures with additional transverse connections of double cables are established. The stiffness of transverse connections is analyzed by the limit parameters of infinite stiffness and zero stiffness. And the non-limit parametric analysis of the stiffness of the transverse connection between zero and infinity. The effects of four parameters, such as cable length ratio, position ratio of transverse connection, cable frequency ratio and cable mass-tension ratio, on the in-plane free vibration frequency of the first four order system are studied. Based on the results of theoretical analysis, the structural model test of double cable system is carried out in this paper. First, the second order frequency and damping ratio in front and out of plane were tested by single cable test. Secondly, the shape memory alloy and the transverse connection of nylon wire were installed at 0.2L 0.4L, and the pre-plane second-order frequency and damping ratio of the system were measured. It is found that the in-plane free vibration frequency of the system with transverse connection is obviously higher than that of single cable. The theoretical calculation of in-plane free vibration is carried out for each working condition, and the analysis error is less than 5 by comparing with the experimental results, which verifies the accuracy of the theoretical analysis model and equation. It has certain guiding significance and practical value for the research of this kind of cable-transverse connection system.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：U441.3;U448.27

【引證文獻(xiàn)】

相關(guān)會(huì)議論文 前1條

1 周亞剛;孫利民;;斜拉橋減振輔助索的參數(shù)分析[A];第八屆全國(guó)振動(dòng)理論及應(yīng)用學(xué)術(shù)會(huì)議論文集摘要[C];2003年

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本文編號(hào)：2110546