本文選題：固有頻率變化率 + 支座病害檢測��； 參考：《華東交通大學》2014年碩士論文

【摘要】：支座作為橋梁結構中重要的組成部分，它的造價雖然在橋梁建設費用中占得比例相對較低，但是支座在橋梁結構中起著重要的作用。它將上部結構的荷載傳遞到墩臺上的同時，滿足了橋梁上部結構在荷載、溫度、混凝土收縮徐變等作用下的自由變形。由于各種原因，支座存在著各式各樣的支座病害，直接影響橋梁的使用壽命和使用安全。現在橋梁支座的檢測方法還比較原始，主要靠人工的尺量、觀察進行，還停留在表觀檢測的階段，對橋梁支座安裝后的實際工作性能的檢測研究還較少。由于支座的高度小、所處的部位光線較暗，而且支座的檢測是高空作業(yè)，這給橋梁支座的檢測帶來了一定的困難，而橋臺上的支座在胸墻的一面檢測就更加的困難。現在支座檢測的儀器還很簡陋，僅靠肉眼觀察、尺量的局限性很大，難以準確反映支座的實際工作狀態(tài)，只有對支座作出定性、定量的分析，才能鑒定其使用情況[1]。 基于橋梁振動理論的檢測技術具有操作簡便、效率高、經濟成本較低、不需要阻斷交通且不對結構造成損傷等優(yōu)點，而且能夠從全局對結構進行把握。橋梁支座作為連接橋梁梁體和橋墩的傳力構件，在結構分析中作為橋梁的邊界條件，對橋梁的振動特性的影響貢獻較大�；诖吮疚姆謩e以實驗和數值計算的方法，討論了運用頻率變化率檢測橋梁支座病害的方法。 首先本文通過分析結構的運動方程，以及橋梁的結構體系，提出支座可以看成整個橋梁結構體系的一部分，它可以簡化為連接橋墩與其橋梁的一根彈簧，支座對于結構的振動的貢獻僅取決于支座的剛度，橋梁的各種病害對橋梁振動特性的影響是由于彈簧的剛度的變化造成的。 其次，在理論分析的基礎上本文以16米鋼筋混凝土空心板式簡支梁橋為基礎，按1:5的比例，制作了三片鋼筋混凝土試驗梁，將支座的剛度變化轉化為支座接觸面積的變化。應用實驗的方法，使用DHDAS5922振動采集系統(tǒng)，采用跳梁法采集了在支座正常布置情況下的自振頻率以及在各支座剛度下降情況下自振頻率，探索了橋梁支座剛度對橋梁的自振頻率的影響。通過研究自振頻率的變化率，得出橋梁支座剛度的變化對橋梁的自振頻率變化率的影響趨勢。通過實驗發(fā)現：支座剛度的降低會影響結構的自振頻率，且結構自身的固有頻率會隨著支座剛度的降低而降低。支座剛度變化對結構自振頻率的影響隨支座位置的不同而不同，靠近橋梁兩側的邊梁支座對自振頻率的影響要大于靠近橋梁中央的支座的影響。由多支座共同發(fā)生病害時，結構頻率的總變化率高于單個支座分別發(fā)生病害時頻率變化率的和，，由于各支座單獨發(fā)生病害時頻率變化率處于同一量級，所以隨著病害支座數量的增加，結構的自振頻率降低率呈階梯變化。由此可以對病害支座的病害程度、病害位置、病害數量進行診斷。 在實驗得出結論后，應用midas FEA有限元軟件按1:1的比例建立了兩座橋的實體模型，應用特征值計算的方法，調整各支座到病害狀態(tài)，對16米空心板式簡支梁橋和一個主跨52米的預應力鋼筋混凝土連續(xù)梁橋進行了模擬。將實驗得出的結論推廣到實際大小的橋梁模型中進行驗證。 通過本文的研究，認為可以應用測試橋梁自振頻率的方法對病害支座的病害程度、位置、病害支座數量進行診斷。
[Abstract]:Bearing as an important part of the bridge structure, its cost is relatively low in the cost of the bridge construction, but the support plays an important role in the bridge structure. It transfers the load of the upper structure to the pier and the pier, and meets the effect of the load, temperature, shrinkage and creep of the upper structure of the bridge. For various reasons, there are a variety of support diseases for the bearing, which directly affect the service life and safety of the bridge. Now the detection method of bridge support is still relatively primitive, mainly by the artificial scale, observation, and the actual working performance after the installation of the bridge support. There are few tests. Because the height of the support is small, the light in the location is dark, and the inspection of the support is high altitude. This brings some difficulties to the detection of the bridge support, and the support on the abutment is more difficult to detect on the side of the wall. It is difficult to accurately reflect the actual working state of the support. It is necessary to make qualitative and quantitative analysis of the bearing so as to identify its usage [1].
The detection technology based on the bridge vibration theory has the advantages of simple operation, high efficiency, low economic cost, no need to block the traffic and not damage the structure, and can grasp the structure from the global. As the transmission part of the bridge beam and the pier, the bridge support is used as the boundary condition of the bridge in the structural analysis. The influence of the vibration characteristics of the bridge is greatly contributed. Based on this method, the method of detecting bridge bearing disease by frequency change rate is discussed respectively by the method of experimental and numerical calculation.
First of all, by analyzing the motion equation of the structure and the structural system of the bridge, it is proposed that the support can be considered as part of the whole bridge structure system. It can be simplified as a spring connecting the bridge pier and the bridge. The contribution of the support to the vibration of the structure depends only on the stiffness of the support and the vibration characteristics of the bridge's diseases to the bridge. The effect is due to the change of stiffness of the spring.
Secondly, on the basis of theoretical analysis, based on the 16 meter reinforced concrete hollow slab simple supported beam bridge, three steel reinforced concrete test beams are made according to the proportion of 1:5. The change of the stiffness change of the support is transformed into the change of the contact area of the bearing. The method of applying the experiment, using the DHDAS5922 vibration acquisition system, is used to collect the beam method. The influence of the stiffness of the bridge bearing on the vibration frequency of the bridge is explored through the study of the change rate of the vibration frequency of the bridge. The influence trend of the change of the stiffness of the bridge bearing stiffness on the frequency change rate of the bridge is obtained by the study of the change rate of the self vibration frequency. The reduction of the stiffness of the seat will affect the vibration frequency of the structure, and the inherent frequency of the structure will decrease with the decrease of the support stiffness. The influence of the change of the stiffness of the support on the vibration frequency of the structure varies with the position of the support, and the influence of the side beam bearing near the bridge is greater than that of the support near the bridge. The total change rate of the structural frequency is higher than that of the single bearing when the disease occurs, and the frequency change rate is at the same order of magnitude in the case of individual bearing diseases. Therefore, with the increase of the disease support, the reduction rate of the vibration frequency of the structure changes step by step. The disease degree, location and quantity of disease support were diagnosed.
After the conclusion of the experiment, the solid model of two bridges is established by using the Midas FEA finite element software according to the proportion of 1:1. The method of eigenvalue calculation is used to adjust the support to the disease state. The 16 meter hollow slab simple supported beam bridge and a prestressed concrete continuous beam bridge with a main span of 52 meters are simulated. The conclusion of the experiment is concluded. It is extended to actual size bridge models for verification.
Through the research in this paper, it is considered that the method of testing the natural frequencies of bridges can be used to diagnose the disease extent, location and number of disease supports.

【學位授予單位】：華東交通大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U445.7

【參考文獻】

相關期刊論文 前10條

1 戰(zhàn)家旺,夏禾,姚錦寶;既有橋梁墩臺自振頻率測試的沖擊振動試驗法[J];北京交通大學學報;2005年01期

2 鞠彥忠,張增軍,陳景彥,王顯利;基于柔度法的結構損傷識別[J];東北電力學院學報;2004年01期

3 李國強,郝坤超,陸燁;彎剪型懸臂結構損傷識別的柔度法[J];地震工程與工程振動;1999年01期

4 譚慶才;;超大跨徑懸索橋的現場振動試驗[J];低溫建筑技術;2012年05期

5 綦寶暉,鄔瑞鋒,李桂華,李志國;基于柔度陣的懸臂彎剪型建筑結構損傷識別方法[J];工業(yè)建筑;2000年04期

6 潘魏曉;王丹丹;;橋墩對連續(xù)梁橋自振特性的影響[J];才智;2013年03期

7 尹娟,郭秀文;基于柔度改變的連續(xù)梁橋損傷診斷研究[J];華東公路;2001年03期

8 張華,閆貴平;基于柔度矩陣的結構損傷識別方法[J];鐵道建筑;2003年06期

9 周興宇,侯暢;板式橡膠支座的檢查與病害分析[J];鐵道建筑;1997年10期

10 金勇;;大跨度鐵路連續(xù)剛構橋動力特性分析[J];鐵道建筑;2013年11期

相關博士學位論文 前2條

1 陳立;基于柔度曲率矩陣的結構損傷識別研究[D];大連理工大學;2009年

2 譚國金;中小跨徑梁式橋動力檢測技術及損傷識別方法研究[D];吉林大學;2009年

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