Analysis On The Main Arch And End Beam Of CFST Arch Bridge With Flexible Tied Bar

The structure of the middle load and CFST arch bridges, with flexible tied bar, is no-thrust arch structure by tensing the tied bar. The sequence of casting concrete into bearing steel tubular arch is one of the most complex and difficult process for the construction of CFST arch bridges. Another problem is that the side arch need burden after tensing the flexible tied bar. Taking the construction monitoring of a CFST arch Bridge in hangzhou city as an instance, many problems on construction of the CFST bridge are discussed in this paper, including: the analysis for simulating construction phase, comparing the plain sequence of casting concrete into bearing steel tubular arc, the trouble removal for the end crossbeam, the optimization of the structure for the safety of end crossbeam.By the analysis for the simulating construction phase, introducing the trouble removal for the end crossbeam, the rule of the internal force for the structure in different construction phase is shown. Some problems, existing in the construction process frequently, are discussed.The effect of the plain sequence on the normal stress of the related cross section is investigated, by the analysis for the sequence of casting concrete into bearing steel tubular arch of concrete-filled steel tubular arch bridge using the three-dimensional FEM. It is shown that the plain sequence of casting concrete have an effect on the concrete, but to no effect on steel tube, because the order of the concrete taking load is decided by the plain sequence of casting it. Therefore, when designing the construction phase, big eyes should be thrown on this plain sequence of casting concrete into bearing steel tubular arc.It is a problem to assuring the safety of the end crossbeam in the arc with flexible tied bar, because it is difficult to prestress the end crossbeam after tensing the tied bar. By optimizing the structure of the side arc and the end crossbeam, it is found that augmenting the weight of side arc is better for the end crossbeam.