环形大跨变截面钢箱梁人行天桥设计

Design of Circular Long-span Variable Section Steel Box Beam Pedestrian Overpass

摘要:

以榆林高新一中环形人行天桥为工程背景，对天桥的方案构思、景观造型和总体布置进行了详细介绍。从梁高和钢板厚度两个因素出发，对大跨变截面钢箱梁进行对比计算和分析，寻找最经济的结构尺寸；对大跨变截面钢箱梁人行天桥进行了人致振动、舒适度分析及减振控制。结果表明：采用大跨变截面钢箱梁能够减少桥墩数量，增加桥下通透感，提高天桥的景观效果；选取合适的梁高和钢板厚度等构造尺寸，可以使天桥具有较好的经济性；较大的桥梁跨度使人致振动问题比较显著，采用适宜的减振控制措施可将行人舒适度控制在舒适的范围内。相应工程经验可为同类工程的设计提供借鉴。

Abstract:

Taking the circular pedestrian overpass of Yulin High-tech Zone No.1 Middle School as the background, the scheme conception, landscape design and overall layout of the overpass are introduced in detail. Starting from two factors of beam height and steel plate thickness, a comparative calculation and analysis of long-span variable section steel box beams are conducted to find the most economical structural dimensions. At the same time, the human-induced vibration and comfort analysis, and the vibration reduction control are carried out for the long-span variable section steel box beam pedestrian overpass. The results show that using the long-span variable section steel box beams can reduce the number of bridge piers, increase the clear view under the bridge, and improve the landscape effect of the overpass. Choosing the appropriate structural dimensions such as beam height and steel plate thickness can make the overpass more economical. The problem of human-induced vibration is more obvious in long bridge spans. Adopting the appropriate vibration reduction control measures can control the pedestrian comfort within a comfortable range. The summary of engineering experience can provide the reference for the design of similar projects.