大跨度铁路连续梁拱组合桥梁结构拱梁合理刚度比研究
Research on Reasonable Stiffness Ratio of Arch Beam of Large-Span Railway Bridge Structure with Continuous Beam Arch Composite
陈亮 1廖治宇 2蔡威 2赵秋2
作者信息
- 1. 广州地铁设计研究院股份有限公司,广东 广州 510000
- 2. 福州大学 土木工程学院,福建 福州 350108
- 折叠
摘要
大跨度连续梁拱组合桥梁具有良好的受力性能与经济效应,其中,拱梁刚度比是该类桥型的 1 个重要设计参数,而以往对拱梁刚度比的研究不够深入和全面.为了解拱梁刚度比对大跨度铁路连续梁拱组合桥梁的影响,以正在建设的福州乌龙江大桥为例,研究拱梁刚度比对桥梁的结构受力特性、梁拱荷载分担和工程量的影响.结果表明:拱梁刚度比对拱肋轴力及主梁、拱脚和拱顶处弯矩影响显著.当刚度比＜1∶73 或＞1∶44 时弯矩最大增长接近 50%,拱梁刚度比的增加,更有利于发挥拱肋的性能;但在拱梁刚度比≥1∶44 时,拱肋刚度增加对整体受力性能提升有限,而当拱梁刚度比≤1∶73时,主梁承受活载增长过快,增加了结构发生局部破坏或整体倒塌的风险.综合考虑,此类桥型拱梁刚度比合理取值范围应在 1∶44～1∶73.工程中为了获得更好的经济效应,可适当减小主梁刚度或拱肋刚度.
Abstract
The long-span continuous beam arch composite bridge has good mechanical performance and economic effect.Among them,the arch beam stiffness ratio is an important design parameter of this type of bridge,but the previous research on the arch beam stiffness ratio is not deep and comprehensive.To understand the influence of arch beam stiffness ratio on long-span railway continuous beam arch composite bridge,taking Fuzhou Wulong River Bridge under construction as an example,the influence of arch beam stiffness ratio on the structural stress characteristics,beam arch load sharing and quantities of the bridge was studied.The results show that the stiffness ratio of arch beam has a significant effect on the axial force of arch rib and the bending moment of main beam,arch foot and arch crown.When the stiffness ratio is less than 1.73 or more than 1.44,the maximum increase of bending moment is close to 50%,and the increase of arch beam stiffness ratio is more conducive to the performance of arch ribs.However,when the arch beam stiffness ratio is greater than or equal to 1.44,the increase of arch rib stiffness has limited improvement on the overall mechanical performance.When the arch beam stiffness ratio is less than or equal to 1.73,the live load of the main beam increases too fast,which increases the risk of local damage or overall collapse of the structure.Considering comprehensively,the reasonable value range of stiffness ratio of arch beam of this type of bridge should be 1.44～1.73.To obtain better economic effect in engineering,the stiffness of main beam or arch rib can be appropriately reduced.
关键词
铁路桥/连续梁拱组合桥梁/拱梁刚度比/荷载分担Key words
railway bridge/continuous beam arch composite bridge/arch beam stiffness ratio/load sharing引用本文复制引用
出版年
2024
NETL
NSTL
维普
万方数据