襄阳市东西轴线二跨汉江特大桥主桥设计

Design of Main Bridge of Second Hanjiang River Bridge on East-to-West Axis of Xiangyang City

襄阳市东西轴线二跨汉江特大桥主桥为独塔混合梁斜拉桥,塔梁墩固结体系,跨径布置为(3×60+320)m。主梁采用扁平箱形混合梁,其中混凝土梁长190.5m,钢梁长309.5m,钢-混结合段长2.0m,设在主跨侧。混凝土桥塔外轮廓呈橄榄形,横桥向由2个马蹄形断面的塔肢构成,在桥塔内设动态风车结构。桥塔每个塔肢下各设1个承台,承台间设横向系梁,承台下行列式布置14根2.5m钻孔灌注桩。斜拉索采用7丝s15.2热镀锌钢绞线,空间扇形布置。边墩及辅助墩横桥向均设置2个矩形柱式墩,下设矩形承台,承台间设1道横向系梁,承台下接4根1.8m的钻孔灌注桩。采用MIDAS Civil 2010进行结构静、动力分析,结果表明该桥结构安全且布置合理。

The main bridge of the Second Hanjiang River Bridge on the East-to-West Axis of Xiangyang City is a single-pylon hybrid girder cable-stayed bridge with rigid fixity system of the pylon,main girder and pier and with span arrangement（3×60＋320）m.The main girder of the bridge is the flat steel and concrete hybrid box girder,of which the part of the concrete girder is190.5mlong,the part of the steel girder is 309.5mlong and the part of the steel and concrete joint section is 2.0mlong and is arranged on the side of the main span.The profile of the concrete pylon of the bridge takes the shape of olive.In the transverse direction of the bridge,the pylon is comprised of the 2pylon legs of the U-shape sections and in the pylon,the dynamic windmill structure is arranged.Under each pylon leg,each one pile cap is arranged and in between the pile caps of the pylon,the transverse tie beams are arranged.Further under a pile cap,14 nos.of2.5m bored piles are arranged in arrays.The stay cables are the 7-wires15.2hot galvanized steel strands and are arranged in the spatial fan shape.For the side and auxiliary piers,in the transverse direction of the bridge,each 2rectangular column piers are arranged and under the piers,the rectangular pile caps are arranged and 1transverse tie beam is arranged in between the pile caps.Further under a pile cap,4nos.of1.8mbored piles are arranged.The MIDAS Civil 2010 is used to conduct the static and dynamic analysis and the results of the analysis indicate that the bridge is structurally safe and is reasonably arranged.