The second step to carry out structural terms, this is the most crucial modeling, the final calculation is correct, largely depends on the model built in is correct. The design of the "MIDAS" software can calculate the internal structure of the control section.

After the completion of the work, they will have to carry out structural checked, the arch bridge the most important thing is to be checked arch section of ultimate bearing capacity and stability. Modeling to run upon completion of analysis, can be "results" in view menu load combination. Combination is of a basic combination of loads, short-term and long-term portfolio. Checking on the following, if checked for load-bearing capacity, then choose the strength of the combination of the envelope; if checked for normal use, then selected the next envelope stress combinations; If checked for deflection, the displacement of the envelope under the selected combination. 

The bridge construction method is a cable used in hoisting method. The cable hoisting law is suitable in surmounting the deep canyon or the deep water area great span arched bridge's installment construction, the arch rib and the matter transport is more convenient, but the deficiency is the arch rib is rambunctious in the airborne docking precision, the arch axis linear control has certain difficulty, the partition are more, its time and quality control's difficulty is bigger, the operating charges are also higher .Therefore, needs to make the transformation and the innovation to the traditional cable hoisting method, and uses some new technologies, the new crafts. Pours into the steel pipe the concretes to use the pump over to go against rises the law .

Through this design to summarize the results of the university’s study ,and with a brief look to the future developments. This paper has given the detailed introductions and clarifications to the size of the entire structure, plane and facade, steel tie shape with CAD drawing pictures.

Keywords: Composite arch bridge；Half-through；Steel pipe concrete；Tied；Structure analysis

目 录

1 绪论 1

1.1 设计的目的与要求 1

1.2 钢管混凝土拱桥的特点 1

1.3 钢管混凝土拱桥的优势 1

1.4 梁拱组合的特点 2

1.5 三跨梁拱组合体系拱桥在国内的发展 2

2 设计依据 3

2.1 设计依据 3

2.2 技术标准 3

2.3 地质资料 3

2.4 主要材料 3

2.5 采用规范 5

3 桥型方案比选 6

3.1 构思宗旨 6

3.2 比选标准 6

3.3 比选方案 6

3.3.1 方案一：简支梁桥方案 6

3.3.2 方案二：中承式钢管混凝土拱桥方案 7

3.3.3 方案三：连续梁桥方案 7

3.4 方案点评 7

3.5 方案确定 8

4 总体布置及主要尺寸 9

4.1 结构总体布置拟定 9

4.2 截面尺寸拟定 11

4.2.1 拱肋 11

4.2.2 吊杆