钢板碳纤维组合加固双曲拱桥应用技术研究

【作者】 薛兴伟；

【导师】 刘洪瑞；

【作者基本信息】 广东工业大学 ， 岩土工程， 2005， 硕士

【摘要】 双曲拱桥加固方法众多,但是结合拱的一个重要特征—变截面拱的受力特性—进行的加固方案未为所见。 当主拱肋或主拱圈在加固以后成为变截面,变截面的形成使得拱结构受力特性发生变化。研究并利用变截面拱的特性对拱桥进行加固,是本课题的主要研究内容。 通过理论分析与实际工程结合,本文研究得出以下结论: 1.变截面拱的弯矩在很大程度上取决于拱截面的惯性矩Ⅰ的变化规律。在惯性矩自拱顶向拱脚逐渐增大的无铰拱,随着截面惯性矩的增大,截面的弯矩也增大。在加固过程中采用增大拱脚惯性矩,会使得拱结构的受力重新分配:拱脚的弯矩因拱脚的惯性矩的相对增大而增大;拱顶的弯矩因拱顶的惯性矩的相对减小而减小。相当于将拱顶的荷载卸载到了拱脚。据此,提出钢板碳纤维组合加固双曲拱桥。 2.使用钢板碳纤维组合加固双曲拱桥,对拱顶存在病害的拱桥,可以直接减轻拱顶的负担;使用钢板碳纤维组合加固双曲拱桥,结合了两种加固方案的施工特点。 同时文中研究讨论了以下几个问题: 1.提出并讨论了实腹段采用板单元,建立利用板单元模拟实腹段的自重及联合作用的拱桥模型。讨论了实腹段板单元与主拱圈梁单元的连接问题,得出了实腹段与主拱圈连接模型在不释放板单元梁端弯矩下也可以得出合理计算结果的结论; 2.探讨了主拱圈的截面换算的方法,明确了利用模量进行截面换算是较为贴切计算方法; 3.提出了手算拱轴系数过程中,实腹段在计算其对L/4和拱脚的弯矩时,应在L/4处将实腹段分为两个不同的部分进行计算的计算方法。更多还原

【Abstract】 There are lots of ways by which the double arch bridge can be successfully reinforced. Therefore, one measure that is based on the tapered arch section mechanics mechanism has never been used.After reinforced, the arch section become the tapered arch section which makes the mechanics mechanism changed. This research brings forward a new measure which is based on the change. Based on the practical engineering, the article draws the following conclusion:1. The moment of the arch section lies on the change of the moment of inertia. To the moment of inertia get bigger from arch tope to the no gemel arch footsie, the moment get bigger from arch tope to the arch footsie. Utilizing thischaracteristic, the author puts forward the reinforced measure—steelplate-carbon fibre reinforce the double arch bridge which can "transfer" the load from the arch top to the arch footsie which can directly lighten the burden of the arch top.2. The measure of steel plate-carbon fibre reinforce the double arch bridge not only utilizes the arch section’s mechanics mechanism, but also exerts the strongpoint of two reinforce measures.In the same time, the research discusses the following problems:1. Bring forward the new arch model which uses the plate element to simulate the self-weight and the combining function and discuss the connecting problem between the beam element and the plate element. Drawing conclusion that the model no end releasing can also well simulate the practice.2. Discussing the method of the section conversion and drawing the conclusion that the method which is base on the Modulus of Elasticity.3. Bring forward the new calculate method that point out that in the course of calculating the dead load , the solid abdomen segment should be devided into two different segment.更多还原