兰溪大桥钢管砼刚架系杆拱设计

福建省安溪县兰溪大桥主跨跨径为80m的下承式钢管砼刚架系杆拱，这种结构既具有固定拱施工方便的优点，又由于系杆承担了绝大部分的水平推力，使下部结构工程数量较省．本文介绍了兰溪大桥主跨的方案设计要点和计算要点．结构受力分析和面外弹性屈曲采用SAP93程序进行空间分析，面内稳定验算采用钢管砼等效简支柱简化计算方法，系杆和吊杆则参照斜拉桥中斜拉索的规定进行验算．同时介绍了施工要点

DESIGN OF CFST RIGID-FRAMED TIED ARCH OF LANXI BRIDGE

The main span of Lanxi bridge on Anxi county in Fujian province is down - bearing concrete - filled - steel - tube(CFST)rigid - framed tied arch. This kind of structure not only has the advantage of convenient to build as a fixed arch, but also economics the substructure for its tie rods and its design calculation. The structure inner - forces and its out - surface elastic stability are calculated by space finite elements program of SAP93. The inner - surface stability bearing capacity is checked by a simplified method that the arch is set as a simple CFST column. The tie robsand hanger robs are checked referring to the cable of cable - stayed bridge. The main point of construction is also introduced in this paper.