马蹄河大桥施工过程分析研究_1-5.docxVIP

 PAGE \* MERGEFORMAT 15 大跨径钢筋混凝土拱桥悬臂浇筑施工过程分析作者简介：胡大琳（1959—），男，教授，博士，硕士生导师，主要研究桥梁结构理论、结构可靠度、桥梁结构耐久性、桥梁抗震等。 陈定市（1988—），男，在读硕士，主要研究桥梁结构理论、桥梁抗震、桥梁结构耐久性等。 胡大琳，陈定市 （长安大学，西安，710064） 摘要：大跨径钢筋混凝土拱桥造型优美和建设经济，在国内外得到了广泛应用并具有广阔的发展前景。目前国内大部分钢筋混凝土拱桥采用缆索吊装法施工，而极少采用悬臂浇筑法施工。采用斜拉索扣锚悬臂浇筑施工的拱桥有两个关键问题：一是施工过程合理的控制张拉索力问题，即以适当的方法计算和优化各施工阶段控制张拉索力，以保证施工阶段结构的安全及成拱的线形和内力满足设计要求，并可进一步改善成拱内力状态；二是各施工阶段???稳定性问题。本文总结了采用悬臂浇筑施工拱桥扣锚索力的确定方法，分析了各种方法的优缺点和适用性，并以马蹄河大桥（净跨径180m的钢筋混凝土悬链线箱型拱桥）为例，对大跨径钢筋混凝土拱桥主拱采用斜拉索扣锚悬臂浇筑施工的全过程进行了详细分析。结果表明，采用零弯矩法对拱桥悬臂浇筑进行施工阶段索力调整容易实现各施工阶段的内力（或应力）及线形控制目标，成功解决了拱桥采用悬臂浇筑施工阶段分析的关键问题。另外采用该工法施工的拱桥施工阶段的稳定性与扣锚索系统的关系密切，合理的扣锚索系统不仅可以控制拱圈的内力和线形，也可以控制施工阶段的稳定性。 关键词：钢筋混凝土拱桥；斜拉扣锚；悬臂浇筑；索力优化；稳定性 Analysis of Long Span Reinforced Concrete Arch Bridge in Cantilever Casting Construction Process HU Dalin, CHEN Dingshi (Chang’an University, Xi’an, 710064) Abstract: Long span reinforced concrete arch bridges have been widely used in China and abroad, and have broad prospects of development with the beautiful shape and economic benefits. At present most of reinforced concrete arch bridges are constructed with cable-hoisting erection method and few with the cantilever casting method in China. Two critical problems need to be solved if reinforced concrete arch bridge is constructed with cable stayed cantilever casting method: the first is to control the reasonable cable force in the construction process, this means appropriate method should be used to calculate and optimize the cable force of each construction stage to ensure the structure safety, alignment and internal force of main arch and meet the design requirements, further more internal force state of the arch can be improved. The second is to ensure the structure stability of each construction stage. In this paper the methods used to calculate the cable force are summarized, and the advantages and disadvantages and the applicability of these methods are analyzed. Matihe Bridge (catenary reinforced concrete box arch bridge with clear span of 180m