横梁间距、刚度对大跨度叠合梁斜拉桥承载力的影响

【作者】 林尔渺；

【导师】 郑振；

【作者基本信息】 福州大学 ， 结构工程， 2002， 硕士

【摘要】 横梁虽然不被看作是斜拉桥的主要构件，设计中却不能忽略它的作用。横梁的正确受力分析、设计计算以及材料的使用已成为整个设计中较重要的一部分。因此本文的目的就是分析在静载作用下，横梁间距、刚度的改变对斜拉桥整个结构的影响。 以青州闽江大桥这座主跨长605m的大跨度叠合梁斜拉桥为例，利用ANSYS大型通用程序建立成桥阶段、悬臂阶段的空间模型，在计算中考虑了材料非线性和几何非线性的影响。通过计算，分析、比较不同的横梁间距、刚度，本文发现： 1、斜拉桥的破坏形式有强度破坏、失稳破坏，或二者兼而有之，横梁间距、刚度的改变将改变斜拉桥破坏的形式； 2、减小横梁间距或增加其刚度，在一定程度上有助于提高整体结构的极限承载能力，但这种作用非常微小； 3、横梁间距、刚度对横梁自身的受力有很大的影响； 4、横梁间距、刚度的改变对主梁、拉索、桥塔的影响非常微小。更多还原

【Abstract】 Transverse beams have been considered as subordinate structure for cable-stayed bridge, but in real design they can’t be neglected. The correct analysis, computation, and the use of material in transverse beams have been an important part in the entire design.The analytical example is Min-River Cable-Stayed Bridge, which is the third longest cable-stayed bridge and the longest composite beam cable-stayed bridge in the world, with main span 605m. The paper set up a 3D model of the bridge with ANSYS finite element program, considering the geometrical and material non-linearity. After evaluation and comparison of the different space and rigidity, some conclusions have been got:1. Cable-stayed bridge will be destroyed for strength, lost of stability, or for both. The change of space or rigidity of transverse beams will alternate the failure reason.2. Transverse beams will to some degree affect the ultimate capacity of cable-stayed bridge, the less space or the more rigidity, the more capacity. However, there is a limitation to improve capacity by the way. When exceeding the limitation, the capacity will be otherwise cut down.3. The space and rigidity have great influence on the behavior of transverse beams.4. The space and rigidity have little influence on the behavior of behavior of girders, tower and cables.更多还原