本文選題：吊桿索力測試 + 吊桿破損��； 參考：《蘭州交通大學》2014年碩士論文

【摘要】：由于吊桿受力狀態(tài)復雜，又受到銹蝕、疲勞等因素的影響使其發(fā)生破損，吊桿破損會引起吊桿系內力重分布，所以在拱橋設計中針對吊桿增加破損安全計算是很有必要的。這樣不僅可以明確地計算出吊桿破損對其它吊桿系、拱肋及系梁受力狀態(tài)的影響以及吊桿破損對拱橋穩(wěn)定性的影響，而且對提高拱橋整體的安全性具有很重要的意義。 為了探討下承式鋼管混凝土拱橋吊桿破損對結構體系是否是破損安全的，本文以南水北調中線工程河南葉縣1標段魏崗鋪北跨渠下承式鋼管混凝土系桿拱橋為工程背景，首先，采用振動頻率法分析了吊桿兩端在不同邊界條件下，其理論計算索力與現場標定K值后的實測索力之間的差異。通過計算分析得到：采用等效鉸接法計算得到的吊桿索力與現場標定K值后實測索力比較接近，誤差均在5.5%以內，滿足工程要求。 其次，采用有限元軟件MIDAS/CIVIL分析計算了該下承式鋼管混凝土拱橋在不同吊桿破損工況下的力學性能和空間穩(wěn)定性。 靜力安全性方面，當單根吊桿破損時，剩余吊桿最大應力、應力幅以及橋梁結構受力均滿足設計和規(guī)范要求，單根吊桿破損對該下承式鋼管混凝土系桿拱橋靜力響應影響較小，單根吊桿破損是破損安全的；當有連續(xù)的3對吊桿發(fā)生破損時，這會導致橋梁結構某些位置出現拉應力、位移變化過大等而導致局部混凝土開裂，更嚴重的是引起吊桿的連鎖破損，，從而引起橋梁結構嚴重損傷，甚至整體垮塌。 動力安全性方面，該下承式鋼管混凝土拱橋的振動形式主要表現為拱肋的面外橫向振動、拱橋整體的豎向振動和扭轉振動。拱肋的面外剛度相對較小，面內振型出現晚于面外振型。吊桿的設置使得橋面豎向振動表現為該拱橋的整體豎向振動；吊桿破損對該拱橋拱橫向振動的自振頻率影響較小，而對全橋豎向和扭轉振動影響較大。吊桿的破損將導致橋梁結構豎向和扭轉振動自振頻率的降低，可見吊桿的完好對拱橋整體的安全性至關重要。 穩(wěn)定安全性方面，各工況對應的橋梁結構第一階穩(wěn)定系數在4.85～5.26之間，滿足根據國內已建鋼管混凝土拱橋的設計經驗，認為施工和運營期穩(wěn)定系數大于或等于4的要求；吊桿破損對該拱橋的低階穩(wěn)定安全系數影響較小，即吊桿破損對結構體系的影響是破損安全的。其失穩(wěn)形式主要表現為拱肋橫向面外失穩(wěn)。
[Abstract]:It is necessary to increase the damage safety calculation in the design of arch bridge because of the complex stress state of the suspender and the influence of corrosion and fatigue. The damage of the suspender will lead to the redistribution of the internal force of the suspender system, so it is necessary to increase the damage of the suspender in the design of the arch bridge.In this way, not only can the influence of suspender damage on other suspenders, arch ribs and girders and the stability of arch bridges be clearly calculated, but also it is of great significance to improve the overall safety of arch bridges.In order to study whether the through concrete filled steel tube arch bridge is damaged and safe to the structure system, this paper takes Weigang Pu Bei span canal through tie arch bridge of Weigang Pu North span canal of Henan Province as the engineering background, first of all, the paper takes the middle line project of South-to-North Water transfer Project as the engineering background.The difference between the theoretical calculation of cable force at the two ends of the suspension rod under different boundary conditions and the measured cable force after calibration of K value in the field is analyzed by means of vibration frequency method.Through calculation and analysis, it is concluded that the cable force calculated by the equivalent hinge method is close to the measured cable force after calibration K, and the error is less than 5.5%, which meets the engineering requirements.Secondly, the finite element software MIDAS/CIVIL is used to analyze and calculate the mechanical properties and spatial stability of the through concrete filled steel tube arch bridge under different suspender failure conditions.In the aspect of static safety, when a single suspender is damaged, the maximum stress, the amplitude of stress and the stress of the bridge structure all meet the design and specification requirements, and the failure of the single suspender has little effect on the static response of the through concrete-filled steel tubular tied arch bridge.The breakage of a single suspender is safe, and when there are 3 pairs of suspenders damaged, this will lead to tensile stress in some parts of the bridge structure and excessive variation of displacement, which will lead to local concrete cracking.What is more serious is the chain damage of suspenders, which can cause serious damage of bridge structure and even collapse of the whole bridge.In terms of dynamic safety, the vibration form of the through concrete filled steel tube arch bridge is mainly the lateral vibration of the arch rib, the vertical vibration and the torsional vibration of the whole arch bridge.The out-of-plane stiffness of arch rib is relatively small, and the in-plane mode appears later than the out-of-plane mode.The vertical vibration of the bridge deck is the whole vertical vibration of the arch bridge, and the damage of the suspension rod has little effect on the natural frequency of the transverse vibration of the arch bridge, but has a great effect on the vertical and torsional vibration of the whole bridge.The damage of suspension rod will lead to the reduction of natural vibration frequency of vertical and torsional vibration of bridge structure. It can be seen that the integrity of suspension rod is very important to the safety of the arch bridge as a whole.In terms of stability safety, the first-order stability coefficient of bridge structure corresponding to each working condition is between 4.85 and 5.26, which meets the requirement that the stability factor of construction and operation period is greater than or equal to 4 according to the design experience of the steel tube concrete arch bridge built in China.The damage of suspenders has little effect on the low order safety factor of the arch bridge, that is, the damage of the suspenders is safe to the structural system.The main form of instability is lateral instability of arch rib.
【學位授予單位】：蘭州交通大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U441;U448.22

【參考文獻】

相關期刊論文 前9條

1 李俊峰;淺談鋼管混凝土結構的應用與優(yōu)缺點[J];包鋼科技;2001年03期

2 段波,曾德榮,盧江;關于斜拉橋索力測定的分析[J];重慶交通學院學報;2005年04期

3 趙洋;李樹山;李曉克;;系桿拱橋吊桿索力測試研究[J];工程抗震與加固改造;2011年04期

4 張通;孫建平;季日臣;范琴鋒;石明星;;下承式鋼管混凝土系桿拱橋力學特性分析[J];甘肅科學學報;2010年01期

5 賀修澤,付曉寧;斜拉索的索力測試[J];中外公路;2002年06期

6 鐘善桐;鋼管混凝土結構在我國的應用和發(fā)展[J];建筑技術;2001年02期

7 朱玉,吳鴻慶;系桿拱的近似基頻公式[J];蘭州鐵道學院學報;1999年05期

8 王坤;;下承式拱橋考慮吊桿失效的穩(wěn)定性分析[J];交通標準化;2011年12期

9 方志,張智勇;斜拉橋的索力測試[J];中國公路學報;1997年01期

本文編號：1764331