张家界大峡谷异型玻璃悬索桥设计关键技术

Key Techniques of Design of Special Shape Glass Floor Suspension Bridge over Zhangjiajie Grand Canyon

张家界大峡谷玻璃桥为人行景观桥,兼具景区行人通行、游览、蹦极、溜索、舞台功能。为实现功能要求,基于特定的建设条件,确定该桥采用空间索面地锚式悬索桥,主缆跨度430m,加劲梁跨度373m。全桥4根塔柱均为钢筋混凝土独柱结构,西、东两侧塔柱横向中心距分别为45m、50m,塔顶不设横梁连接塔柱。西侧两锚碇为隧道式锚,东侧两锚碇为重力式锚。加劲梁为纵、横梁体系,边纵梁内灌注混凝土,钢纵、横梁间露空部分铺设钢化夹胶玻璃。采用张开量大的空间主缆、梁内压重、优化结构气动外形等措施改善桥梁的抗风稳定性;采用不同形式的TMD、TLD及电涡流阻尼器,并在主梁顶面设置玻璃球等措施进行桥梁的振动控制。目前该桥运营状况良好,达到了预期目标。

Zhangjiajie Grand Canyon Glass Floor Bridge is a scenic pedestrian bridge that is required to have the varied functions of the pedestrian passage,sightseeing,bungee jump,cableway sliding and the stage for performance show in the scenic area of the grand canyon.To achieve the functions of the bridge in the design and in accordance with the given construction conditions,the bridge is designed as a ground-anchored suspension bridge with spatial cable planes.The span length of the main cables of the bridge is 430 mand of the stiffening steel girder is 373 m.The 4tower columns supporting the main cables for the whole bridge are all the reinforced concrete single column structures.The transverse c/c spacing distances of the tower columns on both the west and east sides are respectively 45 mand 50mand at the tops of the towers,the cross beams are not arranged for connecting the tower columns.The two anchorages of the bridge on the west side are the tunnel anchorages while on the east side are the gravity anchorages.The stiffening girder is the structural system of the longitudinal girders and cross beams.In the edge longitudinal girders,the concrete is cast and on the hollow parts among the longitudinal girders and cross beams,the tempered laminated glasses are laid.The measures of utilization of the spatial main cables with great opening amount,placement of the ballast in the longitudinal girders and optimization of the structural dynamic profile are taken to improve the wind stability of the bridge.The tuned mass dampers（TMD）,tuned liquid dampers（TLD）and the eddy current dampers of the different types are utilized and on the stiffening girder,the glass balls are arranged as well to control the vibration of the structure.Currently,the bridge has been in good operation and the anticipated design targets of the bridge have been well achieved.