斜拉桥索梁锚固区局部分析

发布时间：2018-01-20 00:12

本文关键词： 斜拉桥钢锚箱混凝土锚固块混合单元模型力学特性　出处：《西南交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,斜拉桥发展十分迅速,国内外多座斜拉桥的跨径己进入特大跨径范围内。斜拉桥索梁锚固结构受力集中、构造复杂,是斜拉索连接主梁的重要结构,其受力状态是衡量桥梁结构工作性能的重要指标。因此,在斜拉桥设计研究中,索梁锚固结构往往作为重要构件成为斜拉桥研究者重点关心的部位之一。目前为止,国内外研究者往往运用节段模型试验手段研究斜拉索与主梁锚固结构的力学特性,节段模型通常仅加载斜拉索的索力,端部的边界按固定或者自由处理。试验模型边界条件的不确定性,造成节段模型与实桥结构受力存在差异,能不能把节段模型试验结果用于实桥结构还有待确定。同时考虑到经济性问题,全桥模型试验又是不可行的,且索梁锚固结构构造形式各异,局部应力分布各不相同,更不可能做大量的全桥模型试验。因此,准确确定节段模型的边界条件尤为重要,是决定节段模型试验成败的关键。四川省某斜拉桥为独塔单索面混合梁斜拉桥,钢箱梁部分和混凝土箱梁部分的索梁锚固结构分别采用钢锚箱式和混凝土锚块式锚固结构。本文运用桥梁结构局部计算的精细化计算方法一混合单元模型法,对该桥两种索梁锚固结构进行受力分析,研究该桥索梁锚固结构的受力特点。全桥混合单元模型利用通用有限元软件Midas/Civil建立,模型中索梁锚固结构及附近梁体用板或实体单元模拟,全桥其它部位用梁单元模拟,计算分析斜拉索与主梁锚固区应力分布规律。通过混合单元模型计算,给出两种索梁锚固结构在不同荷载作用下应力分布,分析应力集中及传力机理。最后,结合相关规范及现有的研究成果,评价该桥梁锚固结构受力性能,并探讨索梁锚固结构的合理设计方法,用于指导结构设计。
[Abstract]:In recent years, cable-stayed bridges have developed rapidly, and many cable-stayed bridges at home and abroad have entered the super-span range. Cable girder Anchorage structures of cable-stayed bridges are concentrated in force and complicated in structure, which is an important structure of cable-stayed cable-stayed bridge connecting main beam. The stress state is an important index to evaluate the performance of the bridge structure. Therefore, in the study of cable-stayed bridge design. Cable-beam Anchorage structure is often regarded as an important component of cable-stayed bridge researchers focus on one of the parts. So far. Researchers at home and abroad often use segmental model test to study the mechanical properties of cable and main beam Anchorage structure. The segmental model usually only loads cable force. The boundary of the end part is treated as fixed or free. The uncertainty of the boundary condition of the test model results in the difference between the segmental model and the real bridge structure. Whether the segmental model test results can be applied to the real bridge structure is still to be determined. Considering the economic problem, the full-bridge model test is not feasible, and the structure of cable beam Anchorage structure is different. The local stress distribution is different, and it is not possible to do a lot of full-bridge model tests. Therefore, it is very important to accurately determine the boundary conditions of the segmental model. A cable-stayed bridge in Sichuan Province is a cable-stayed bridge with single tower and single cable. The cable girder Anchorage structure of steel box girder part and concrete box girder part are respectively steel anchor box structure and concrete anchor block type anchor structure. Two kinds of cable beam Anchorage structure of the bridge are analyzed and the mechanical characteristics of the cable beam Anchorage structure of the bridge are studied. The hybrid element model of the whole bridge is established by the general finite element software Midas/Civil. In the model, the cable beam Anchorage structure and the nearby beam body are simulated by plate or solid element, and other parts of the bridge are simulated by beam element. The stress distribution of cable and main beam Anchorage zone is calculated and analyzed. The mixed element model is used to calculate the stress distribution. The stress distribution of two kinds of cable-beam Anchorage structures under different loads is given, and the stress concentration and force transfer mechanism are analyzed. Finally, combined with relevant codes and existing research results, the mechanical performance of the bridge Anchorage structure is evaluated. The reasonable design method of cable-beam Anchorage structure is discussed to guide the structure design.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

【参考文献】