中承式钢箱提篮拱桥设计

Design of Half-Through Steel Box Basket-Handle Arch Bridge

武汉市汉口至阳逻江北快速路新河大桥采用(48+196+48)m的中承式钢箱提篮拱桥。主拱采用等截面钢箱提篮拱,截面尺寸为2.5 m×4 m(宽×高),拱肋分为25个节段,采用斜拉扣挂缆索吊装法施工。2片钢箱主拱肋间设5道横撑,并外包装饰板。边拱采用预应力混凝土结构,为等高矩形截面,截面尺寸为2.5 m×4 m(宽×高),采用现浇法施工。主跨桥面系采用“钢纵横格子梁+混凝土桥面板”的组合梁体系,边跨桥面系采用混凝土格子梁体系;沿全桥通长设置钢绞线柔性系杆。吊杆采用环氧喷涂钢绞线成品索。拱座采用大体积混凝土结构,拱座主拱外包混凝土处设置装饰段,使边、主拱曲线流畅过渡。建立整体及局部模型进行计算分析,结果表明结构安全可靠。

The Xinhe Bridge on Hankou-Yangluo River North Fast Corridor in Wuhan is a half-through steel box basket-handle arch bridge with spans of 48,196 and 48 m.The main arch is a steel box basket-handle arch with constant cross section measuring 2.5 m(width)×4 m(height).The arch was divided into 25 sections that were erected by using fastening stays.The two arch ribs were connected by five cross struts and encased with ornamental plates.The side arch adopts the cast-in-situ prestressed concrete structure,which has a rectangular cross section with constant height and with a dimension of 2.5 m(width)×4 m(height).The deck of the main span is formed of the latticed stringers and cross beams covered by concrete slabs,while the deck of the side spans is the concrete lattice beam system.The through flexible ties formed of steel strands were installed.The hangers are finished cables formed of steel strands with epoxy coating.The arch seats are mass concrete structures,where the main arch is also encased with concrete as decoration to allow the smooth transition of side and main arches.The overall and local models were established to carry out calculation and analysis.The results demonstrate that the structure is safe and reliable.