【作者】 高涛；

【导师】 高日；

【作者基本信息】 北京交通大学 ， 桥梁与隧道工程， 2012， 硕士

【摘要】 随着桥梁结构越来越多地用于跨越铁路、公路、河流等,转体施工法凭借着其明显的优势在桥梁建设中也得到越来越广泛的应用。转体桥的优势在于它可以适应桥位处的地形搭设支架现场浇筑,然后通过球铰和滑道组成的转盘结构转体就位,不影响通航,不中断过往车辆,施工安全方便,免去复杂的高空作业,具有明显的社会和经济效益。桥梁施工监控不仅是桥梁施工技术的重要组成部分,而且也是确保桥梁施工宏观质量的关键。本文依托秦皇岛城市西部快速路跨京哈铁路转体桥,对该T形刚构桥进行施工监控。参照有限元软件Midas计算值,对箱梁和转体墩控制截面的应力以及拆架后的梁体变形进行监测和结果分析。同时,对梁体位于转体墩根部的截面进行水化热监测并利用有限元软件进行温度场和应力场模拟计算,提出控制混凝土内外最大温差,尽可能防止裂缝发生的合理建议。由于施工过程中不可避免的误差,拆架后转动体的实际中心往往与理论中心不重合,而且偏心距的大小将直接影响转体能否平稳安全的进行。因此在转体前需进行称重试验,并且根据称重结果进行配重,以保证转体的顺利进行。转体梁脱架后由多点弹性支承变成悬臂状态,在转体前靠球铰独立支撑一段时间,过往列车和风对该桥安全稳定性的影响不可忽视。本文通过现场测试列车经过时产生的振动时程,采用时程分析法对大悬臂状态转体梁的振动响应进行了计算,分析了列车通过对转体梁稳定性的影响。此外,还研究了风对大悬臂转体梁稳定性的影响,研究结果为转体梁的施工控制提供参考。更多还原

【Abstract】 Bridges are increasingly utilized to cross over other traffic lines such as railways, highways and rivers, and the swing method of bridge construction is becoming more and more widely used on account of its obvious advantages. Supporting frames, on which concrete will be poured during construction, are built on both sides of the terrain. The beam of the bridge will be swiveled to the correct position by the rotatable structures consisting of ball bearing and slides, without interrupting naval navigation and road traffic. Due to safe and convenient construction and the elimination of the complex high-altitude operations, the swing method has significant socio-economic benefits.Bridge construction monitoring is not only an important part of the bridge construction technology, but also the key to ensuring the macro quality of construction. This paper focuses on the construction of a swing bridge on Qinhuangdao’s West Highway over the Beijing-Harbin Railway. The stress from a cross section of the box girder and swivel pier, and beam deformation after the removal of stents were closely monitored and analyzed based on the calculated values of finite element analysis. Meanwhile, heat of hydration in the cross-section of the swivel pier base was also monitored and calculations of temperature and stress field were simulated by using the finite element software. Reasonable recommendations for controlling the maximum temperature difference between the concrete inside and outside to prevent cracks were given.Due to the inevitable errors in the construction process, the actual center of the rotating body after the removal of stents often does not coincide with the theoretical one. The size of the eccentricity will directly affect whether the rotation could be carried out safely and smoothly. Therefore, it is necessary to have a weighing test and to balance the weight based on the test results before rotation, in order to ensure that the rotating bridge will swivel smoothly.The rotating body gets into a cantilever state after the removal of stents, and needs to stand alone for a short period only relying on the ball hinge before rotation. For that reason, the influence imposed on the bridge by passing trains and wind could not be ignored. Vibration generated by the passing trains was acquired through a field test. When time history analysis method was applied to compute the long cantilever’s vibration response, the influence imposed on the rotating body by passing trains was analyzed. Meanwhile, the influence imposed on the rotating body by wind was also analyzed. The result can provide a reference for the on-site construction control.更多还原