The study about the Pre-camber of bridge construction — the balanced cantilever method

• Main Authors: Wang weilin, 王維麟
• Other Authors: Lai jinhua
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/86736203920664101637

碩士 === 高苑科技大學 === 土木工程研究所 === 96 === Pre-camber control of the cast-in-site balanced cantilever method is a very important link during the construction. If the camber is too different from the original design, the cantilever segments on both sides won’t be connected accurately. It needs exerting another force to connect coercively at the appointed time. But connecting coercively will cause extra stress and the doubt of structure safety. Whether the cast-in-site balanced cantilever method will be successful or not, Pre-camber control is the key-point. To research the tendency divination of the camber development and the identification of abnormality difference are two key-points of camber management control. The former is used to judge the difference of the camber of the two cantilevers before the construction closed up; The latter is used to find out the problems and the solution about the abnormality of arch degree. Because the live load and the work sequence of pour construction will make influence for the camber the period of the construction, it will help to assure that the stress and the alignment of the bridge finished can be satisfied with the design requirement in the future by monitoring effectively and accurately the change of the camber. In this report, the main purpose of the research on the finished alignment on girders and the camber can be satisfied with the requirement of the design. It needs making a strict management method of the camber control of bridge and a standard operation process. It can be used to control the development tendency of the camber of the girders for the trestle through structure analysis, measurement operation, identification difference, identification operation, adjustment of arch degree and feedback process accurately. The development tendency analysis of the camber for the girders adopts the least square method and uses the line linear returned method to estimate beforehand the development tendency of the camber. Then working car pushes forward, measuring the deflection influence of the former segments, to estimate the deformation difference of the former segments after pouring the concrete. Finally, make sure that the information is exact by comparing this difference with the deformation after cementing.