我国钢管混凝土拱桥应用现状与展望

Application of concrete-filled steel tube arch bridges in China:current status and prospects

共收集到截止2015年1月的已建和在建的钢管混凝土拱桥413座(跨径不小于50m)。统计分析表明,钢管混凝土拱桥在我国修建的数量不断增多、跨径不断增大。从行业分布来看,在公路、城市桥梁中的应用仍是主体,在铁路尤其是高速铁路中的应用不断增多。在结构体系方面,上承式、中承式、拱梁组合式、飞鸟式和下承式刚架系杆拱5大类,仍为主要应用的桥型,占总数的85%。在截面形式方面,以圆钢管混凝土为基本单元组成的单圆管、哑铃形和桁式是应用的主流。提篮拱被应用于各种桥型,尤其是大跨度铁路桥。无风撑拱主要应用于120m跨径以下的桥梁,且以斜靠拱和拱梁组合桥为主,截面多采用横向刚度较大的形式。拱肋的材料强度不断地提高,钢管以Q345钢为主,混凝土以C40、C50为主。虽然对桥面系强健性的重视在不断提高,然而强健性好的整体式和具有加劲纵梁的悬吊桥面系的应用还不够普及。钢管拱的架设方法仍以支架法、悬臂法和转体法3种为主,其中悬臂拼装法应用最多,适用跨径最大范围也最广。

Up to January 2015, data of 413 concrete-filled steel tube （CFST） arch bridges with a span no less than 50 m, which have been built or still under construction, were collected in this work. Statistical analysis showed that both the number and span of CFST arch bridges in China have increased continuously. For the distribution of CFST arch bridges in industry, they have been mainly applied to the highway and municipal projects, while their applications in railway, especially in the high-speed railway, have been rapidly growing. In all the bridges, 85 % are composed of five categories of structural system, namely, deck bridge, half-through bridge, arched girder composite type, flying-bird arch bridge and through rigid-framed tied arch bridge. For cross-sectional form of the main arch ribs, the popular forms are single tube, dumbbell-shape and truss, with circular steel tube concrete as the basic element. Basket-handle-like arch bridge has been adopted in various structural systems of CFST arch bridges, especially in the long-span railway bridges. Open arch bridges are mainly used in the bridges with a span no longer than 120m, the majority structures are arch ribs consists of two inclined ones and arch-girder composite structure, and the arch ribs generally have strong stiffness in the transverse direction. Material strength of arch rib has been improved gradually, the majority steel of the steel tube is Q345 and the majority concrete filled is C40 and C50. Though attached attention to the robustness of deck system has been increased continuously, the application of deck system with good robustness in suspension deck floor, such as the integral deck structure or deck structure with stiffening girders, has not been popular yet. The main erection methods of steel tube arches include cantilever erection method, swing method and centering method, among which the cantilever erection method has the widest adaption for various bridge spans and for the large span brisges.