一、钢筋混凝土箱型拱桥的发展及在广西的修建情况 拱桥由于具有造型美观、经久耐用、投资省、易施工、取材方便、便于养护等优点,因而是我国山区公路中采用较广的桥型。特别是钢筋混凝土箱型拱桥的使用和发展,无支架施工技术的广泛应用,又为修建大跨径拱桥创造了有利的条件,使拱桥在大跨径桥梁中重新获得可与其他钢筋混凝土桥相竞争的能力。 本世纪以来,国外钢筋混凝土箱型拱桥(以下简称箱型拱桥)获得了迅速的发展,跨径不断增大。1980年建成的南斯拉夫KRK铁托大桥主孔跨径达390米(副孔244米),成功地采用了无支架悬臂施工。它不仅是目前世界上跨径最大的钢筋混凝土箱型拱桥,也是目前除斜拉桥外已建成的跨径最大的钢筋混凝土桥,充分显示了箱型拱桥所具有的跨越能力。 First, the development of reinforced concrete box arch bridge and the construction of Guangxi arch bridge due to the appearance of beautiful, durable, investment, easy construction, easy access, easy maintenance, etc., which is widely used in our country mountain bridge . In particular, the use and development of reinforced concrete box arch bridge, without the widespread application of stent construction technology, but also for the construction of large-span arch bridge to create favorable conditions for the arch bridge in the long-span bridge regained with other reinforced concrete bridge phase Competitive ability. Since the beginning of this century, the overseas reinforced concrete box arch bridge (hereinafter referred to as the box arch bridge) has gained rapid development and its span has been continuously increasing. Built in 1980, the Yokoslok KRK Tito Bridge has a main span spanning 390 meters (244 meters from the secondary side) and successfully adopted the unsupported cantilever construction. It is not only the largest reinforced concrete box arch bridge with the largest span in the world at present, but also the reinforced concrete bridge with the largest span besides the cable-stayed bridge, which fully shows the span capability of the box arch bridge.