重庆寸滩长江大桥主桥设计

Design of Main Bridge of Cuntan Changjiang River Bridge in Chongqing

重庆寸滩长江大桥主桥为250m+880m+250m的单跨简支钢箱梁悬索桥。该桥设2根主缆,主缆采用预制平行高强钢丝索股结构。全桥共布置57对吊索,吊索采用预制平行钢丝束,与索夹采用销接式连接方式。主索鞍为全铸式结构,鞍底设置座板作为滑动副。散索鞍为底座式结构,底部设置柱面钢支座。主缆锚固系统采用型钢锚固系统。加劲梁采用流线型扁平式封闭钢箱梁,梁高3.5m,宽42m。南、北锚碇均为重力式锚碇,现浇扩大基础,锚体在平面均呈U形。桥塔为钢筋混凝土门式框架结构,两塔柱竖直布置,基础为分离式承台桩基础。

The main bridge of Cuntan Changjiang River Bridge in Chongqing is a single-span simply-supported steel box girder suspension bridge with span arrangement 250 m＋880 m＋250 m. The bridge has two main cables that are the structures of prefabricated parallel high-strength steel wire strands. There are totally 57 pairs of the suspenders arranged for the whole bridge, the suspenders are the structures of prefabricated parallel steel wire strands and are connected with the cable bands by way of pin connection. The tower saddles are the fully cast structures and under a tower saddle, the base plate is arranged and is used as the sliding set. The splay saddles are the base structures and under a splay saddle, the cylindrical steel bearing is arranged. The ancho- ring systems for the main cables are the shaped steel anchoring systems. The stiffening girder of the bridge is designed as the streamlined flat closed steel box girder that is 3.5 m deep and 42 m wide. The anchorage on both the south and north banks are the gravity anchorage, the foundation for each anchorage is the cast-in-situ enlarged foundation and the body of the anchorage is in U shape in plan. The towers are the reinforced concrete portal frame structures. The two columns of a tower are arranged vertically and the foundation of the tower is the pile foundation with separated pile caps.