三跨(140+300+140)连续双塔钢箱梁斜拉桥设计全套(毕业设计)

摘要

桥面系为钢结构，桥塔为钢筋混凝土结构。斜拉桥很早以前就有了，到了近代发展速度十分迅猛，在现代桥梁工程实践中开始广泛应用，其特点是受力性能好、跨越能力大、轻型美观、抗震性能好。是跨越大江大河、海峡港湾等交通障碍的首选桥型。

本设计以斜拉桥设计基本理论和静动力分析为理论基础，以成功修建的斜拉桥为例，根据桥梁的位置、布置形式，拟定桥梁的跨度、矢高、锚索倾角、桥塔高度和截面、塔基形式、锚碇构造等，说明选择相关参数的过程、依据、和考虑的主要因素，然后进行桥面系、拉索、桥塔、锚碇等具体尺寸设计、配筋和验算。由于斜拉桥是超静定结构，计算较为烦琐，故在该设计中，结构单元划分和内力计算采用专业设计软件MAIDAS进行，计算方法为有限元法，使设计工作量大大的简化，内力求出后，根据桥梁规范进行结构内力组合。最后，按容许应力法和极限状态法来验算主要截面，以判定设计的合理性。

本设计的步骤为：根据设计任务要求，依据现行公路桥梁设计规范,综合考虑桥

位的地质、地形条件，经初选后提出了斜拉桥方案、悬索桥、拱桥三个比选桥型。按“实用、经济、安全、美观”的桥梁设计原则，比较三个方案的优缺点。比选后把斜拉桥作为主推荐设计方案，进行了结构细部尺寸拟定、静活载内力计算、钢主梁应力强度、疲劳验算、斜拉桥整体稳定验算、斜拉桥整体强度应力验算、拉索应力及疲劳验算、钢主梁细部结构设计。经分析比较及验算表明该设计计算方法正确，内力分布合理，符合设计任务的要求。

关键词：方案;斜拉桥；拱桥；悬索桥；主推荐设计方案；结构分析；验算。

Abstract

The subject is performed in according with the basic theory of Cable stayed bridge dynamic and stationary analysis theory. The span, main cables tower and cables are designed in line with the arrangement of span. The way choose the parameters and decisive elements are illustrated. Thereafter, the sizes of deck system, main cables, end link, cable bands, storm system and anchorages are designed.

As a highly redundant system, it is inevitably brings us much difficult in the analysis of the internal forces by hand. The computer program, which named MAIDAS are used in course of calculation in order to simply the work. When the internal stress is carried out, the arrangement of internal stress is implemented in light of bridge specification. After checking the items required in the code for the across-sections, we can know the feasibility of the design.

the process of designment：According to the design assignment and thepresent Highway Bridge Specifications, Take the geological and the landform of the bridge site for further analysis, after preliminary selection, three bridge type schemas are presented, they are Cable-stayed bridge, Suspension bridge and Arch bridge. Comparing their characters comprehensively, the Cable stayed bridge is selected as the main design scheme by the philosophy of bridge design as “Practicability, Economy, Security, Beauty”.Throug h drawing up of structure’s dimension, internal force calculation of dead and living load, steel beam stress and strength calculation, fatigue stress calculation, the whole bridge strength calculation, checking computation of cable stress and fatigue stress, living load distortion, drawing up of steel beam’s dimension. The conclusion can be drawn that the design is up to the assignment. Key word: Design ; cable-stayed bridge; Arch bridge;Suspension Bridge; Steel beam;Fitague stress; the main design scheme for further analysis ; Structure analysis and checking computation.