在车辆负载下对长跨甲板型CFST桥的动态反应和冲击因素的研究
Yong Zeng1,2, Nianchuan Yin3,4, Yujie Tan3,4
1State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing, 40074, China. yongzeng@cqjtu.edu.cn.
Scientific reports
|May 13, 2025
概括
长跨度混凝土填充钢管 (CFST) 形桥面临交通负载带来的安全风险. 这项研究表明,标准冲击系数低估了动态效应,需要对长跨度桥梁进行更新的设计和维护.
科学领域:
- 结构工程 结构工程
- 运输工程 运输工程
- 桥梁工程 桥梁工程
背景情况:
- 长跨度混凝土填充钢管 (CFST) 弧形桥梁容易受到安全风险的影响,因为它们的跨度很大,柱子高,在复杂的交通负载下具有动态敏感性.
- 现有的安全评估可能无法充分捕捉这些结构在各种交通条件下的动态反应.
研究的目的:
- 为了研究长跨度CFST桥在不同车辆速度,偏心负载和杆刚性的情况下的动态反应.
- 评估标准冲击系数在评估这些桥梁的安全性方面的充分性.
- 为改善长梁桥的设计,维护和运行安全提供建议.
主要方法:
- 使用有限元建模 (MIDAS) 进行结构分析.
- 采用车辆-桥梁合动态分析来模拟现实世界的条件.
- 分析了武江桥 (504米跨度) 作为一个案例研究.
主要成果:
- 标准冲击系数显著低于对桥梁的实际动态影响.
- 末端柱的侧移冲击系数 (0.426) 远远超过了标准值 (0.05).
- 车辆20m/s和28m/s的速度是动态响应的关键点,异常负载将弧形肋骨上的扭矩效应增加0.236.6.
结论:
- 目前的设计规范不足以评估长跨度CFST桥的局部部件.
- 紧急建议包括加强桥梁甲板维护,车辆速度控制和加强关键元素的动态设计.
- 需要一个多参数协作优化模型来提高这些结构的生命安全.
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