Model Testing Study On The Construction Of Reinforced Concrete Arch Bridge With Cast-in-Situ Cantilever Method

Arch bridge has a long history and a variety of applications in China, and among all the arch bridge types, reinforced concrete (RC) arch bridge is most applied. At present, the main construction methods of long span RC arch bridge in China are arch centering method, cable-hoisting erection method, precast segmental cantilever method, swing method and Melan method. And the cast-in-situ cantilever method has not been applied in all the completed RC arch bridges, however, it has been widely utilized to construct RC arch bridges abroad since 1960s. Especially in recent years, many countries have constructed a lot of RC arch bridges with this method, some of which create the new arch span records of the nations. It is no doubt that the cast-in-situ cantilever method has got fast development abroad. Constructing arch bridge with this method is very appropriate in such precipitous site conditions as cliffy canyons and torrential rivers, and it can also reduce construction cost and period, easily control deformation during construction, have good structural integrity, reduce damage to environment and so on. The advantages of this method make arch bridge more competitive and promote the development of arch bridge.The Baishagou No.1 bridge with a 150m arch span in the Xichang-Panzhihua expressway in Sichuan province is now being constructed with the cast-in-situ cantilever method, which will be the first arch bridge with this method in China. In order to get more understanding of the method and variety of stress and deformation of the arch, so as to provide some references to the real bridge, a 1/5 scale model of the arch was constructed and tested. The thesis is focused on the construction of arch bridge with the cast-in-situ cantilever method, firstly, the development of the method applied in arch bridge and several long span arch bridges constructed with this method in recent years are briefly introduced, secondly, the theory of the construction control of arch bridge with this method is stated, finally, it is emphasized on the design, construction and the result analysis of the model test. And the test shows that the stress and deformation of the arch are reasonable, and the construction method of the real bridge is safe and feasible.