三主桁连续钢桁拱桥静分力特性及稳定极限承载力研究-桥梁与隧道工程专业毕业论文.docx

中南人学硕十学位论文 中南人学硕十学位论文 摘要 摘 要 本文以东平水道连续钢桁拱桥为工程背景，对其静力特性和稳定极限承载能 力进行了研究，主要完成工作如下： (1)利用ANSYS软件建立了三主桁连续钢桁拱桥空间力学计算模型。 (2)研究了大跨径连续钢桁拱桥在活载、温度、制动力及风力作用下主桁杆 件的受力特性，探讨了设计参数对三主桁结构受力性能的影响，包括横梁刚度、 平联刚度等。 (3)对三主桁连续钢桁拱桥和两主桁连续钢桁拱桥进行模拟对比，比较两种 体系的刚度，主桁杆件、横梁及横联等的受力特性，并总结了两种结构体系各自 的优缺点。 (4)分别采用线弹性、几何非线性、双重非线性三种不同的方法分析东平水 道连续钢桁拱桥的极限承载力。通过比较三种方法的分析结果，研究上述方法使 用的条件。 (5)总结和比较目前国内学者对稳定安全系数的定义方法，对定义最低容许 值提出本文的建议。 (6)研究荷载形式、初始缺陷、材料强度等参数对连续钢桁拱桥极限承载力 影响。 关键词连续钢桁拱桥，三主桁，稳定极限承载力，双重非线性，两主桁 中南人学硕十学位论文 中南人学硕十学位论文 Abstract Abstract On the study of Dong Ping Bridge，a large—span steel truss arch bridge，the present paper gives an analysis of its static characteristics and ultimate bearing capacity．The main result of this paper are presented as follows： (1)On the basis offinite element analysis software ANSYS，space mechanical model of three—truss continuous steel—truss arch bridge has been established． (2)On the basis of long-span continuous steel—truss arch bridge，stress characteristics of main truss has been studied under the various conditions，such as live loads，temperature loads，braking loads and wind loads，etc．Meanwhile，the impact of various factors on the bridge has been discussed，such as the stiffness of transverse beam and combination among spans． (3)this paper gives an comparison between three—truss and two—truss continuous steel truss arch bridge，including of stiffness in two systems as well as stress characteristics of main truss members．transverse beams and lateral combination．The respective advantages and disadVantagesof the two systems has been studied at the same time． (4)the ultimate bearing capacity of Dong Ping continuous steel truss arch bridge has been analyzed by using three different ways，which are elastic，non—linear geometry,double nonlinear methods．The applied conditions of these three methods has been presented through the analysis and results of the comparison． (5)On the summary and comparison of definition of stability safety factor among the current scholars，this paper gives