不对称斜塔斜拉桥的受力和设计分析研究  

Mechanical and Design Analysis for Cable-stayed Bridge with Asymmetric Leaning Tower

作　　者：杨勇[1] 刘英伟 刘能文[1] 韩清海[3] 

机构地区：[1]北京市市政工程设计研究总院有限公司,100082 [2]中国水电顾问集团北京勘测设计研究院有限公司,100024 [3]北京建达道桥咨询有限公司,100015

出　　处：《特种结构》2014年第6期68-72,39,共6页Special Structures

摘　　要：斜塔斜拉桥是一种概念较新的桥梁结构形式,其独特之处在于倾斜的桥塔、轻盈的主梁、优美的外形,但是结构的不对称性导致其受力复杂、施工难度大。本文结合一有背索、跨径不对称、拉索不对称的斜拉桥的工程实例,通过对其静力力学模型分析,可知此类斜拉桥既要关注桥梁的整体平衡,也要关注主梁、主塔结构的局部平衡。通过对张拉索力和施工阶段分析的总结,可知刚性支撑连续梁法初估索力时只顾及了梁的受力,而忽略了塔的受力,要结合主梁、主塔的平衡条件对成桥索力进行调整才能得到合理的成桥状态。通过主塔、主梁的设计分析,得出桥梁的预应力布置、主梁截面形式、拉索的施工步序应依据施工阶段分析中主梁与主塔的受力情况最终确定。该桥目前已施工完毕,该桥的设计经验可以为同类桥梁的设计与施工提供参考。Cable-stayed bridge with leaning tower is a relatively new form of bridge structure, it is unique in inclined bridge tower, light main girder and beautiful appearance, but the asymmetry of structure would result in complex stress and difficult construction. In this paper through the static mechanical model analysis of a cable-stayed bridge with back stay, asymmetry cable and span, it is known that both the intergral balance of bridge and balance of main girder and tower should be focused on for this kind of cable-stayed bridge. By analyzing the tension cable force and construction stage, it is known that for preliminary estimate of cable .force, because the rigid support continuous beam method only consider the stress of the beam and ignore that of the tower, so that it is necessary to adjust the cable foree of completed bridge combined with the equilibrium conditions of the main girder and main tower, then the reasonable finished state would be got. Through the design analysis of the main girder and main tower, it is concluded that the prestressing arrangement, cross section form of main girder and construction steps of cable should be final determined according to the force of the main girder and the main tower in construction stage analysis. Now the bridge has been completed, and this bridge design experience can provide reference for the design and construction of similar bridges.

关 键 词：斜塔斜拉桥 刚性支撑连续梁法 整体平衡 局部平衡 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]