摘要：钢桁梁桥由桥面系、制动联结系、联结系、桥面、主桁、支座以及桥墩组成。钢桁梁桥由桁架杆件组成，尽管从整体上看钢桁梁桥以受弯和受剪为主，但具体到每根桁架杆件则主要承受轴向力。与实腹梁相比使用稀疏的腹杆代替整体的腹板，从而节省钢材和减轻结构自重，又由于腹杆钢材用量比实腹梁的腹板有所减少，钢桁梁可做成较大高度，从而具有较大的刚度及更大的跨越能力。但是，钢桁梁的杆件和节点较多，构造较为复杂，制造较为费工。按照主桁的支承方式不同，分为简支钢桁梁桥、连续钢桁梁桥和悬臂钢桁梁桥；按照桥面位置不同，分为上承式钢桁梁桥、下承式钢桁梁桥。 本课题主要讨论单线铁路 64 米下承式栓焊简支刚桁梁桥。基于本课题，在这里主要涉及到了刚桁梁桥的内力计算以及截面的设计。  21952
毕业论文关键词：钢桁梁桥；下承式；截面   
Abstract:  Steel truss is composed of  the bridge deck system, brake coupling,
coupling, bridge, main girder, bearing and the composition of bridge piers. Steel truss
is composed of truss rods, although the overall steel truss is given priority to with the
bending and shear, but specific to each truss rods are mainly subject to axial force.
Compared with the plain girder using the thin abdomen rod instead of the whole web,
thereby saving steel and lighten the weight, and due to CHS steel consumption less
than plain girder web steel truss beam can be made bigger height, which has great
stiffness and larger span ability. However, steel truss beam bar and the node is more,
structure is relatively complex, create more work.  According to the main girder
supporting way is different, pided into continuous steel truss girders of simply
supported steel truss, and cantilever steel truss; According to the bridge deck position
is different, pided into steel truss deck, concrete-filled steel truss.
This topic focuses on single railway 64 meters concrete-filled bolt welding
simply-supported just for members. Based on this topic, mainly involved here just for
members of the internal force calculation and the design of cross section.
 Key Words: Steel truss; The concrete-filled; Cross section
目录
绪论   1
课题的目的和意义    1
国内外研究现状与水平  ..  1
发展趋势  ..  3
1 设计资料  .  4
1.1 基本资料..  4
1.2 设计内容..  5
1.3 设计要求  .  5
2 主桁杆件内力计算 .  6
2.1 主力作用下主桁杆件内力计算..  6
2.2 横向风力作用下的主桁杆件附加力计算  ..  9
2.2.1平纵联效应的弦杆附加力    9
2.2.2桥门架效应的端斜杆和端下弦杆附加力  ..  10
2.3 制动力作用下的主桁杆件附加力计算    11
2.3.1 下弦杆制动力计算..  11
2.3.2端斜杆制动力计算  ..  13
2.4 疲劳内力计算  ..  13
2.4.1疲劳轴力  .  13
2.4.2 吊杆疲劳弯矩  14
2.5  主桁杆件内力计算  .  15
2.5.1主力组合  .  15
2.5.2主力和附加力组合  ..  15
3 主桁架杆件截面设计 .  19
3.1 主桁杆件的截面形式以及外轮廓尺寸确定  19
3.2 下弦杆截面设计    20
3.3 上弦杆截面设计    23
3.4 端斜杆截面设计    25
3.5 中间斜杆截面设计  .  27
3.6 吊杆截面设计  ..  29
3.7 腹杆高强度螺栓计算  ..  30
4 弦杆拼接计算和下弦杆端节点设计 .  32 单线铁路64米下承式栓焊简支刚桁梁桥+CAD图纸:http://www.751com.cn/gongcheng/lunwen_14389.html