梁—拱组合桥梁拱梁相互作用分析

发布时间：2018-02-28 18:41

本文关键词： 梁拱组合桥梁集中荷载均布荷载协作机理　出处：《兰州交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：梁拱组合桥梁顾名思义是在拱式桥梁结构中，将梁和拱两种基本结构组合起来，共同承担荷载。该类桥型集结了两者的优点，，使得结构受力合理，材料利用率高并且造型美观。常见的梁拱组合桥梁有平行式和提篮式两种类型。本文针对平行式梁拱组合桥梁推导出了相应的实用计算公式，并对拱梁相互作用机理及影响因素进行探究。（1）将均布荷载作用下连续梁拱组合桥梁的吊杆力模拟成均布膜张力。根据结构力学的方法，推导出该类桥型在均布荷载作用下的实用计算公式。结合工程实例与有限元计算结果进行比较，并对公式计算结果的误差原因进行了分析。其后分别采用“四次抛物线”型膜张力修正了均布膜张力；采用余弦形式的膜张力修正了连续膜张力，并提出了相应的修正系数；（2）探究了拱、梁轴向变形对吊杆膜张力及拱肋和主梁变形的影响，并对柔性系杆刚性拱的计算公式进行了简化；（3）从静态和动态两个方面，对连续梁拱组合桥梁的变形协调条件提出了两种不同的解释；（4）根据结构力学的方法，推导出连续梁拱组合桥梁的弹性中心，并对影响弹性中心的因素及关系进行了分析；（5）根据结构力学的方法，推导出了集中荷载作用下连续梁拱组合桥梁的主梁、拱肋及吊杆的内力影响线。探究了梁拱截面抗弯刚度比、矢跨比及荷载作用位置对结构内力的影响；（6）在等效膜张力假定的前提下，推导出连续梁拱组合桥梁的拱梁荷载比、拱梁内力比和拱梁变形比的实用计算公式。分析了梁拱截面抗弯刚度比、拱肋矢跨比、主梁边中跨径比、吊杆等代抗弯刚度及拱梁轴向刚度系数对结构内力的影响规律。并从以上三个方面，探究了梁拱组合桥梁拱、梁相互作用机理。
[Abstract]:Beam-arch composite bridge is, as the name implies, that in the arch bridge structure, two basic structures of beam and arch are combined to bear the load together. The material utilization ratio is high and the shape is beautiful. There are two types of beam and arch composite bridge: parallel type and basket type. This paper deduces the corresponding practical calculation formula for parallel beam and arch composite bridge. The mechanism and influencing factors of arch-beam interaction are also discussed. 1) the suspension force of continuous beam-arch composite bridge under uniform load is simulated to uniform film tension. According to the method of structural mechanics, The practical calculation formula of this kind of bridge under uniform load is deduced, and the results of finite element calculation are compared with engineering examples. The error causes of the formula calculation results are analyzed. After that, the uniform film tension is corrected by the "four times parabola" membrane tension, the continuous membrane tension is corrected by the cosine form, and the corresponding correction coefficient is put forward. 2) the influence of the axial deformation of arch and beam on the membrane tension of suspender, the deformation of arch rib and main beam is investigated, and the calculation formula of flexible rigid arch is simplified. (3) from static and dynamic aspects, two different interpretations of deformation coordination conditions of continuous beam-arch composite bridges are put forward. 4) according to the method of structural mechanics, the elastic center of continuous beam-arch composite bridge is deduced, and the factors affecting the elastic center are analyzed. 5) according to the method of structural mechanics, the main beam, arch rib and suspender of continuous beam-arch composite bridge under concentrated load are derived, and the ratio of bending stiffness to bending stiffness of beam and arch section is discussed. The influence of rise-span ratio and load position on the internal force of the structure; 6) on the premise of the assumption of equivalent membrane tension, the practical formulas for calculating the load ratio of arch beam, internal force ratio of arch beam and deformation ratio of arch beam of continuous beam and arch composite bridge are derived. The bending stiffness ratio of beam and arch section and the ratio of arch rib span to span are analyzed. The influence of the ratio of span to span, the equivalent flexural stiffness of suspenders and the coefficient of axial stiffness of arch beam on the internal force of the structure is studied, and the interaction mechanism of beam and arch is discussed from the above three aspects.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441

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