【作者】 刘庆志；

【导师】 宁晓骏；

【作者基本信息】 昆明理工大学 ， 道路与铁道工程， 2008， 硕士

【摘要】 连续刚构桥具有跨越能力大,行车舒适性好,经济实用等优点,是大跨度桥梁的主要形式。现在大跨度连续刚构桥基本上均采用挂篮分节段施工,本文针对连续刚构桥的悬臂施工过程及受力特点,提出一种预应力优化设计的方法。其设计思想是根据悬臂施工阶段和成桥状态按T构弯矩平衡配置预应力束,对连续刚构桥纵向预应力束的腹板束下弯问题作了优化分析,并对跨中底板连续束的合理配置作了研究分析。本文以云南小湾水电站淹没区某连续刚构桥为工程背景,根据施工过程,考虑混凝土的收缩徐变的影响,对预应力束在最大悬臂状态、成桥状态腹板束下弯锚固位置进行了分析对比,结果表明大跨连续刚构桥腹板束必须设置下弯,下弯锚固的最佳位置为箱梁的形心或H/2高度处;在满足于施工过程中的受力情况下,对于底板连续束的布置范围进行了研究,在跨中正弯矩区段设置合理数量的底板连续束会使桥梁结构的受力更合理。通过对该桥预应力束的优化分析,得到的结论可以为连续刚构桥设计提供参考。更多还原

【Abstract】 Continuous Rigid Frame Bridge is one of the main form of the large-span bridges. It has some strongpoint such as large span, comfortable driving and economic cost. Now large span Continuous Rigid Frame Bridge is constructed one section by one section in the way of cantilever. In this paper, base on the cantilevered construction characteristics of continuous rigid frame bridge, one optimization method of prestressing tendon was presented. Its design concept is based on the construction phase and the cantilever bridge on T-stage moment equilibrium configuration prestressed beams, Analysing and investigating the problem of the curved web beam prestressing tensons and how to set up a reasonable amount of continuous prestressing teasons in bottom plate of box section.Beased on a Continuous Rigid Frame Bridge in Xiaowan Hydropower Station in Yunnan Province, considing constrction process and shrinkage and creep of concrete, analysis the anchor position of the curved web beam prestressing tendon in the largest cantilever beam and the construction phase, the result is that the large-span continuous rigid frame bridge must be set up the curved web beam prestressing tendon.The best location for the anchor of the curved web beam prestressing tendon is the box beamcentroid or half height of the box beam;Seting up reasonable amount ofprestressing tendons in bottom plate of box in middle span so as to forcingformance of bridge is reasonable. These obtained conclustion will give some references for practical prestressing tendons designing of continous rigid frame bridges.更多还原