宁波外滩大桥附属人行桥设计  

Design of Subsidiary Footbridges of Waitan Bridge in Ningbo

作　　者：万鹏[1] 马骉[1] 

机构地区：[1]上海市政工程设计研究总院(集团)有限公司,上海200092

出　　处：《世界桥梁》2013年第4期5-9,共5页World Bridges

摘　　要：宁波外滩大桥主桥为(225+82+30)m独塔四索面异形钢斜拉桥,外侧设置全长203.9m的曲线异形悬挑钢人行桥(采用悬臂工字梁受力,内、外侧设置箱形边纵梁),人行桥与主桥钢箱梁结合成一体。为确保该结构形式静力、动力特性满足要求,采用MIDAS Civil有限元软件建立该桥空间有限元模型,研究附属人行桥设计关键技术。研究得出附属人行桥设计关键技术包括:箱形边纵梁顺桥向间隔30～37.5m设置1条断缝,调索完成后安装主跨靠近2/5、1/4和1/8位置的箱形边纵梁;采用铝合金桥面;在边跨人行桥增加7对钢管斜撑,钢管上、下部设置半圆球节点。该桥采取上述构造和施工措施后可避免附属人行桥过度参与整体受力,降低应力水平,同时保证动力特性与舒适性满足要求。The main bridge of the Waitan Bridge in Ningbo is an irregular steel cable-stayed bridge with span arrangement of （225＋82＋30） m. The bridge has one pylon and four cable planes. What makes the bridge quite distinctive is that an irregular curved steel footbridge with a total length of 203.9 m is cantilevered out from each side of the main girder. For the footbridges, the I-shaped cantilever beams are the load-bearing structures, of which box stringers are added to both the inner and outer edges. Structurally, the footbridges are integrated with the steel box girder of the main bridge. To ensure that the static and dynamic behaviors of the structure could meet relevant requirements, the finite element software of MIDAS Civil was used to set up the spatial finite element model of the bridge to study the key technologies that would be employed in the design of the subsidiary footbridges. It was drawn from the study that the following key technical details should be included and given enough concern： the breaking joints in the box stringers should be set at intervals of 30-37.5 m along the bridge length; the box stringers close to the locations of 2/5, 1/4 and 1/8 of the main span should be installed after the completion of the tuning of the stay cables; it would be better to choose the aluminum alloy bridge deck; 7 pairs of steel pipe diagonals should be added to the parts of the footbridges that were along the side spans of the main bridge and the joints at the upper and lower ends of the steel pipe should be treated as semicircle ball joints. By applying the aforementioned structural arrangement and construction measures, the subsidiary footbridges are not prone to excessively participate in the global load bearing behavior the bridge, the stress level can be reduced and the dynamic performance and travelling comfort can be guaranteed.

关 键 词：斜拉桥 附属人行桥 静力特性 动力特性 有限元法 桥梁设计 

分 类 号：U448.11[建筑科学—桥梁与隧道工程]