The main bridge of Changchun Yitong River Bridge is a three-span flying bird type irregular shape concrete-filled steel tube (CFST) arch bridge.The arches of the bridge are composed of the main arch ribs, stability arch ribs, diagonal bracings and lateral bracings.The Vshape legs are of prestressed concrete (PC) two-cell and single-box structure.The main girder for the side spans is the PC girder that is rigidly fixed with the V-shape legs and the springs of the main arches.The main girder for the main span is the steel box girder that is simply supported on the brackets at the springs.Totally 16 pairs of the inclined hangers are provided for the main arches and 6 nos.of the horizontal tied members are arranged for the whole bridge.The test for bearing capacity of the large-scale CFST columns, the scale-down model test for static force of the whole bridge and the simulated vibrostand test for earthquake are made in compliance with the theory of similarity and the key techniques and control factors in the construction process are summarized.The results of the tests show that the safety factors of the strength of the main arch ribs are great and the global static performance and seismic performance of the bridge can all satisfy the requirements in the relevant codes.%长春伊通河大桥主桥为三跨飞燕式钢管混凝土异型拱桥.该桥拱肋由主拱肋、稳定拱肋及斜撑和横撑构成;V腿采用预应力混凝土单箱双室箱形结构;边跨加劲梁采用预应力混凝土梁,与V腿及主拱拱脚段固结,主跨加劲梁采用钢箱梁,简支在拱脚处牛腿上;主拱共设16对斜吊杆,全桥共设6根水平系杆.根据相似理论进行大尺寸钢管混凝土柱承载力试验、全桥缩尺模型静力试验及模拟地震振动台试验,并总结该桥施工过程中的关键技术和控制要素.试验结果表明该桥主拱肋强度安全系数较高,其整体静力性能和抗震性能均满足规范要求.
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