斜拉桥主梁应力监测与合拢控制研究

【作者】 陈晔；

【导师】 黄平明； 许汉铮；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2006， 硕士

【摘要】 现代斜拉桥属高次超静定结构，设计和施工的难度都较大。对于悬臂分段现浇施工的斜拉桥，因其施工过程中受温度、混凝土收缩徐变的影响，结构受力复杂，为了保证桥梁在施工过程中的结构受力安全及成桥的线形与内力符合设计要求，必须对桥梁施工过程进行严格的控制。 本文以江苏淮安大桥为工程背景，就主梁重要截面的剪力滞效应及主跨合拢过程控制等问题进行研究。通过建立淮安大桥有限元分析模型，对其进行施工过程的模拟分析，研究施工过程中各工况作用下结构受力最不利截面的应力分布情况，得到各工况下主梁结构的内力和应力分布状态。通过分析发现，剪力滞效应对预应力混凝土斜拉桥有较大的影响，在施工中必须考虑，以免箱梁混凝土局部应力超限。另外，采用桥梁结构分析专用软件对淮安大桥主桥进行了仿真分析，并且应用合拢施工过程的计算结果，对不同情况下主梁的合拢施工进行对比分析，研究了大跨度混凝土斜拉桥在合拢施工过程中内力和线型的变化规律。更多还原

【Abstract】 Cable-stayed bridge is a kind of highly statically indeterminate structure, and its designand construction is very difficult. For cable-stayed bridge by cantilever and segment construction, as a result of the effects of temperature difference, concrete shrinkage and creep during construction course, stress condition of structure is very complex. For the bridge’s structure stress security in the construction process and guaranteeing the bridge linear conforms to the design requirement, construction control is very important for realization of design scheme.Taking Huaian Bridge of Jiangsu as an example, the shear lag effect of the controlling cross-section and the process control of cantilever construction was studied in the thesis. In the thesis, simulation analysis over construction process of Huaian Bridge was presented, and obtained the inner forces and stress of main girder structure under the most unfavorable load condition during construction. After analysis, it was noticed that shear lag effect had a significant influence on the displacement of prestessed concrete bridge, and it must be taken into consideration during the construction. Then on the basis of introducing the construction process of the Huaian bridge, analysised the construction course fully, and analysised comparatively the result of each girder segment construction simulatio, and studied the variation philosophy of the line style of large cable-stayed bridge during closure constuction.更多还原