摘要钢桁架桥梁在现实实际中随处可见。钢桁架桥梁一般由主桁，上平纵联，下平纵 联，桥面系和桥门架等组成。其中下弦杆、上弦杆和竖杆构成主桁架，它的作用是将 载荷传递给墩台并且主要承受竖向的载荷。联结系一般分为上平纵联和下平纵联。主 要的作用就是配合主桁架一起稳定结构，增强稳定性并且承受横向载荷以免桥梁剧烈 晃动。当然，桥面系是桥梁必不可少的一部分，横梁，纵梁和他们之间的联结系一般 构成了桥面系。84940

本文主要对桥梁的安全性能和经济性能做了简单的分析和研究。将三维建模后的 模型导入到 Workbench 中进行力学性能的分析，安全性能就是针对钢桁架桥的静力学 分析，模态分析和疲劳分析，防止桥梁的强度不够，确保桥梁的各个力学参数符合许 用强度。而经济性能就是针对桥梁的总用钢量，使得桥梁在满足安全性能的前提下， 耗费越少越好。本课题在现实中也是具有很大的探索价值的，这样的研究肯定会对祖 国的桥梁事业起到促进作用，同时也会促进 CAE/CAD 等技术在工程中的应用。

毕业论文关键词：钢桁架桥梁；有限元分析；安全；经济

Abstract Steel truss bridge in the real practice everywhere。 Steel truss bridge generally consists of the main truss, flat longitudinal, lower flat longitudinal deck and bridge gantry system and other components。 Wherein the lower chord, chord and vertical bars constitute  the main truss, its role is to load transfer to the pier and the main bear vertical loads。 Bracing is generally pided into upper and lower flat longitudinal flat longitudinal。 The main role is with the main truss together a stable structure, and enhance the stability of the bridge to withstand lateral loads to avoid violent shaking。 Of course, the bridge deck system is an integral part of, beams, bracing stringer and between them generally constitute Deck System。

This paper focuses on the safety and economic performance of the bridge to do a simple analysis and research。 The three-dimensional model into the modeled analysis Workbench in mechanical properties, safety performance is for the steel truss bridge statics analysis, modal analysis and fatigue analysis, to prevent the strength of the bridge is not enough to ensure that all mechanical parameters of the bridge in line with promises with strength。 The economic performance is the total amount of steel for the bridge, so bridge meet the safety performance of the premise, consuming as little as possible。 In reality, this project is of great value to explore, such research will certainly be the cause of the motherland's bridge played a role in promoting, but also to promote the CAE / CAD technology application in engineering。

Keywords:Steel truss bridge;Finite Element Analysis;Safety ;Economic

目 录

第一章 绪论 1

1。1 选题的目的和意义 1

1。2 国内外发展现状 1

1。3 通用有限元软件的介绍 1

1。4 本文主要研究内容 2

第二章 钢桁架桥力学计算和三维建模 3

2。1 钢桁架桥梁的基本介绍 3

2。2 钢桁架桥梁计算参数的确定 5

2。3 主桁架杆件的内力计算 5

2。4 主桁架杆件截面的计算 8

2。4。1 主桁架杆件的截面形式 9

2。4。2 主桁架杆件的外轮廓尺寸计算