摘要
新颖自锚式悬索桥的主缆采用钢管混凝土索套的半刚性索;加劲梁采用预应力混凝土箱梁,主缆作为预应力体外索,在跨中正弯矩区段穿入箱梁内,托起箱梁并起主缆中央扣的作用,形成梁索组合结构。桥梁的恒载由主缆承担,预应力混凝土箱梁承担主缆索力的水平分力,箱梁用于减少自锚式悬索桥的活载作用下的挠度,并承担压力与弯矩。这类桥梁建筑高度约为l/40～l/50,它适用于跨径100m左右的二跨或三跨连续梁桥。施工方法过去一般采取满堂支架现浇,因此限制了本桥型的适用范围。在上海松江施贤路油墩港桥,将偏心转体施工方法首次应用于自锚式悬索桥,并利用盆式支座为转体的磨心及滑道,缩小了主桥跨径及省略钢筋混凝土磨心的精工细作,施工工艺简便易行,使上述桥型可适用于不同场合。
A new kind of self-anchored suspension bridge is designed in the paper.Its main cable is made of half-rigid rope which is surrounded by the concrete steel tube;The prestress concrete box girders are used as stiffened girder;The cables are anchored both in the end and in the middle of the main girder where is in the region of positive bending moments,so the main cables are used as pre- stressed external cables to form girder-rope combined structure.The dead load is supported by main cables,and the horizontal force of the main cable and moment are supported by the prestress concrete box girders.The using of box girders can reduce deformation of live loads.This kind of bridge's building height is 1/40～1/50,and is suitable for 2-span or 3-span 100m continuous beam bridge. Traditional rafting cast-in-situ support restricts the application of this kind of bridge.During the constructing of Youdunxiang Bridge,the swinging technique is firstly applied to self-anchored suspension bridge's construction.In addition,basin support is used as the spherical surface and slipway,which reduces the span and avoids difficulty of RC spherical surface.The technique is simple and easy which promotes the application of the new kind self-anchored suspension bridge.
出处
《上海公路》
2007年第3期23-27,5,共5页
Shanghai Highways
关键词
自锚式悬索桥
体外索
转体施工
盆式支座
self-anchored suspension bridge
external tendon
swinging construction
basin support
