湖州市长兜港大桥主桥设计与施工

Design & Construction of Main Bridge of Changdougang Bridge in Huzhou

湖州市长兜港大桥主桥为国内首座双斜塔无背索部分斜拉桥,跨径布置为(50+100+50)m,采用塔梁固结、塔墩分离的结构体系。主梁采用单箱五室预应力混凝土变截面连续箱梁,全宽36m;主塔采用钢筋混凝土结构,向边跨侧倾斜约26°;斜拉索采用平行钢绞线拉索,为竖琴式的索面布置。采用MIDAS/Civil软件建立有限元模型进行主桥结构的计算分析,结果表明该桥各项指标均满足规范要求。主梁采用挂篮悬臂浇筑施工,主塔采用劲性骨架节段施工并利用斜拉索进行平衡,在主塔施工完成后进行主梁的跨中合龙。

The main bridge of Changdougang Bridge in Huzhou is the first partial cable-stayed bridge with double-skew tower without backstays in China. Its span layout is (50+100+50) m. The structure system is adopting tower-beam consolidation & tower-pier separation. The main girder is a single-box & five-compartment prestressed concrete continuous box girder with variable cross-section, with a full width of 36 m;the main tower is reinforced concrete structure, inclining about 26°to the side span;the cable-stayed cables are parallel stranded cables, which are arranged on the cable plane of the harp type. The finite element model of the main bridge structure is established by using MIDAS/Civil software. The results show that all the indexes of the bridge meet the requirements of the code. The main girder is constructed by hanging basket & cantilever. The main tower is constructed by rigid skeleton section and balanced by cable. After the construction of the main tower, the main girder is closed in the middle of the span.