昌平钢-混凝土结合连续刚构桥的设计与施工

昌平跨线桥采用两联跨度为(37+60+79+42.5)m及(42.5+79+42.5)m的钢-混凝土结合连续刚构型式.该桥主梁为钢-混凝土结合梁,钢箱梁采用单箱单室直腹板截面,桥面板为钢筋混凝土结构,钢箱梁在中墩处与混凝土墩身固结,下部结构墩柱均采用矩形桥墩.采用有限元程序MIDAS Civil建立全桥空间结构计算模型,对该桥进行静力计算分析,结果表明钢箱应力及结构强度均满足规范要求.为减少对桥下交通的影响,该桥钢箱梁采用工厂预制、现场吊装的方法施工,预制桥面板按先跨中后支点的顺序施工,采用间断法安装.

Design and Construction of Steel and Concrete Continuous Composite Rigid Frame of Changping Overpass Bridge

The Changping Overpass Bridge is a steel and concrete continuous composite rigid-frame bridge arranged in two continuous units,each being(37+60+79+42.5) m and(42.5+79+42.5) m.The main girder of the bridge is designed as a steel and concrete composite one,of which the steel box girder is of the single-cell,single-box and vertical web section and the deck slabs are the reinforced concrete structure.The box girder is rigidly fixed with the concrete pier shaft at the intermediate pier and all pier columns of the bridge are the rectangular ones.The finite element program MIDAS Civil was used to establish the calculation model for spatial structure of the whole bridge,the static force of the bridge was calculated and analyzed and the results of the calculation and analysis proved that the stress and structural strength of the box girder could meet the relevant requirements in the codes.To minimize the interference of construction to the traffic under the bridge,the box girder was fabricated in shop and lifted in place at the bridge site.The precast deck slabs were installed by the discontinuous method in the sequence of the parts of the bridge at the midspan first and the parts close to the supports late.