【摘要】：橋梁結構處在不斷變化的自然環(huán)境條件下,將不可避免地受到周圍環(huán)境的影響。周圍環(huán)境的影響主要體現在：太陽日照輻射、周圍氣溫變化等。由于混凝土為熱的不良導體,橋梁結構在太陽輻射等作用下將產生非均勻溫度場。這種時刻變化的瞬態(tài)溫度場會在混凝土結構,特別是超靜定結構體系中產生較大的溫度自應力,從而對橋梁結構的耐久性產生潛在威脅。交替變化的溫度場產生的溫度自應力有時候甚至比結構其他外荷載作用更大,因此揭示混凝土結構溫度的分布規(guī)律,具有十分重要的理論意義和現實意義。現場實測資料表明：不同地理環(huán)境條件和大氣環(huán)境條件對橋梁結構的溫差應力影響十分明顯。不同氣候條件、不同地區(qū)的混凝土溫度分布具有不同的特點,特別是溫差較大的區(qū)域其溫差荷載對橋梁結構的應力狀態(tài)及位移撓度的影響更為明顯。我國河南林州太行山地區(qū)由于日照強烈,早晚溫差大,這種特殊的氣候條件對橋梁結構的溫度場分布研究具有重要的意義。本文結合林州露水河特大橋,對橋梁結構箱梁在典型日照溫差下的溫度分布狀態(tài)進行觀測分析,并應用ANSYS建立箱梁截面模型模擬其溫度分布,確定了符合林州太行山地區(qū)的溫度梯度分布模式,具有重要的理論意義和工程實用價值。本文運用ANSYS軟件建立了露水河大橋在懸臂施工階段的三維實體模型,計算分析了溫度荷載對施工過程箱梁的豎向位移和縱向應力的影響。最后,通過MIDAS/CIVIL建立露水河特大橋的三維梁單元全橋模型,計算分析了溫度荷載對成橋運營階段箱梁的豎向位移和縱向應力的影響,認為橋梁在運營階段的溫度效應不容忽視,在設計中應充分考慮溫度荷載效應對橋梁結構的影響。
[Abstract]:Under the changing natural environment, the bridge structure will inevitably be affected by the surrounding environment. The influence of the surrounding environment is mainly reflected in the solar radiation, the change of surrounding temperature and so on. Because concrete is a bad conductor of heat, the bridge structure will produce non-uniform temperature field under the action of solar radiation and so on. This kind of transient temperature field will produce large temperature self-stress in concrete structure, especially in statically inconstant structure system, which will pose a potential threat to the durability of bridge structure. The temperature self-stress produced by alternating temperature field is sometimes even greater than other external loads of the structure, so it is of great theoretical and practical significance to reveal the temperature distribution law of concrete structure. The field measured data show that the temperature difference stress of bridge structure is obviously affected by different geographical environment conditions and atmospheric environment conditions. The temperature distribution of concrete in different regions has different characteristics, especially in the area with large temperature difference, the influence of temperature difference load on the stress state and displacement deflection of bridge structure is more obvious. Due to the strong sunshine and large temperature difference between morning and evening in Taihang Mountain area of Linzhou, Henan Province, this special climatic condition is of great significance to the study of temperature field distribution of bridge structure. In this paper, combined with Linzhou Lushuihe Bridge, the temperature distribution of box girder of bridge structure under typical sunshine temperature difference is observed and analyzed, and the cross section model of box girder is established by ANSYS to simulate the temperature distribution. The temperature gradient distribution model in accordance with the Taihang Mountain area of Linzhou is determined, which is of great theoretical significance and practical value in engineering. In this paper, the three-dimensional solid model of Lushui River Bridge during cantilever construction is established by using ANSYS software, and the influence of temperature load on the vertical displacement and longitudinal stress of box girder during construction is calculated and analyzed. Finally, the three-dimensional beam element model of Lushuihe Bridge is established by MIDAS/CIVIL, and the influence of temperature load on the vertical displacement and longitudinal stress of box girder in the operation stage of the bridge is calculated and analyzed. It is considered that the temperature effect of the bridge in the operation stage can not be ignored, and the influence of the temperature load effect on the bridge structure should be fully considered in the design.
【學位授予單位】：西南交通大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U441.5;U448.23

【引證文獻】

相關碩士學位論文 前1條

1 李琛;預應力連續(xù)剛構橋施工預拱度設置和溫度應力分析[D];重慶交通大學;2017年

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本文編號：2492894