【作者】 朱卫国；

【导师】 项贻强；

【作者基本信息】 浙江大学 ， 桥梁与隧道工程， 2003， 硕士

【摘要】 预应力混凝土连续梁拱组合体系桥梁主要由拱肋、系梁、吊杆、横梁及桥面系组合起来共同承受荷载，是一种结构受力合理、外形美观、新颖的结构体系。它利用拱肋承担压力，系梁预应力束抵抗拱端推力，吊杆及纵横桥面系结构承受桥面荷载，既克服了传统拱桥巨大的拱端推力，又改善了连续梁桥较大的弯矩和剪力的受力状况，最大限度地发挥了拱梁混凝土和预应力钢筋各自的特点，经济效益显著。 本文针对该类型结构设计施工的特点，从以下几个方面较系统地作了研究： 1．研究提出用弹性支承连续梁法荷载横向分布理论计算空间梁拱组合式桥梁的荷载横向分布，从而将空间问题转化为平面计算问题，进而用平面杆系有限元理论分析求解梁拱拱片各杆件截面的内力和挠度，并用空间有限元理论和通用程序建立空间模型进行对比计算。在此基础上，以一座实际的预应力混凝土连续梁拱组合体系桥梁为工程背景，采用一般的试验研究方法对该桥进行了荷载试验研究，并将有关的荷载试验结果与理论计算值作了比较，结果表明：所提出的弹性支承连续梁法计算值，与空间有限元分析理论值及荷载试验测试值基本吻合。 2．对预应力混凝土连续梁拱组合体系桥梁的自振特性进行分析和动载试验研究，给出了前几阶的固有频率及相应的振型。 3．研究探讨了矢跨比、拱梁刚度比等参数对预应力混凝土连续梁拱组合体系桥梁结构内力的影响，并得出合理的取值范围，为设计人员选取结构参数提供参考。 4．采用空间有限元程序分析拱肋的弹性稳定性，了解拱肋、风撑、吊杆等因素对稳定性的影响程度，以指导设计并确保施工安全可靠。更多还原

【Abstract】 The prestressed continuous beam-arch composite bridges are a special structural system where the horizontal thrust of the arch rib is absorbed by a prestressed tie at deck level. In some cases,this type of structure is preferable because it doesn’t have the large thrust at the spring hi traditional arch bridges and the somewhat large bending moment and shear force in traditional beam bridges. As a result,the performances of the prestressing reinforcement can be efficiently utilized. In this paper,the studied works are list as follows:1) The theory of elastically supported continuous beam method is brought forward to transfer spatial continuous beam-arch composite bridges into plane structure. The plane finite element method is used to calculate inner forces and deflections of each beam and arch. At the same time,spatial finite element model is created for contrast. All of the researches are carried out on the background of a spatial continuous beam-arch composite bridges,and the relative loading experimental results are compared with the calculated values. It indicates that the theory of elastically supported continuous beam method load lateral distribution is a kind of simple convenience and safe practical engineering calculation method.2) The suspender force and correlated modality is analyzed with the use of general calculation program ANSYS .During testing suspender force,the influence of the rigidity of suspender must be considered.3) The influences on the internal forces by some variable parameters such as the ratio of the rise to span and the stiffness ratio are compared .The optimal range of these parameters is pointed out and some advances are also given.4) The lateral elastic stability of the arch rib with 3-dimention FEM program is analyzed,some influence factors such as suspender,arch rib and wind brace etc. are comprehended. The results may ensure the construction and be useful to designers.更多还原