Simplified Calculation Method of Pedestrian Suspension Bridge under Vertical Load

DOI：

 作者 单位 胡习兵1，向思宇1?覮，方辉1，2，袁智深1 （1. 中南林业科技大学 土木工程学院，湖南 长沙410004； 2. 中机国际工程设计研究院责任有限公司，湖南 长沙410004）

为解决人行悬索桥在竖向荷载作用下计算挠度变形过程繁琐、有限元分析复杂等问题，根据人行悬索桥柔性较大的结构特征，忽略其加劲梁的刚度作用，考虑主缆IP点处位移、边缆垂度效应、几何非线性等因素，提出了一种简化计算方法. 对不同跨度、不同矢跨比桥梁的主缆无应力长度和跨中挠度变形进行了试算，并根据试算结果对简化计算方法的适用范围和误差进行了分析，验证了计算方法的计算精度和适用范围. 以跨度为117 m的人行悬索桥为例，利用本文计算方法对该桥分别在成桥状态和受竖向荷载作用时的悬索桥力学性能进行了分析，并与有限元分析和试验检测结果进行了比较. 结果表明：本文所提简化计算方法实用性较好，能在实际工程中为人行悬索桥快速求解和有限元分析校核提供参考.

In order to solve the tediously calculative problem of deflection and finite element analysis of the pedestrian suspension bridge under vertical load, a simplified calculation method was proposed by considering the flexible structure of pedestrian suspension bridge, neglecting the stiffness of the stiffening beam, and considering the IP displacement of the main cable, the cable sag effect, and the geometric nonlinearity. The stress-free length and midspan deflection of bridge main cables with different spans and different rise-span ratios were calculated, and the application scope and error of the simplified calculation method were analyzed based on the results of the trial calculation. The calculation accuracy and application scope of the method were verified. Taking a pedestrian suspension bridge with a span of 117 m as an example, the mechanical properties of the suspension bridge under completed and vertical load state were analyzed by the calculation method in this paper, and compared with the results of finite element analysis and test. The results show that the simplified calculation method proposed has good practicability and can provide a reference for the rapid solution and verification of finite element analysis result of pedestrian suspension bridges in practical engineering.