Abstract:In order to solve the problems that when a large skew cast-in-situ frame bridge crosses under a small-radius curve railway, there is a shortage of railway overhead range, the conversion of overhead system support points is cumbersome, the horizontal overhead span is small, and the frame bridge is difficult to be cast at one time and the conventional method is not applicable to such conditions, a double overhead reinforcement system of longitudinal beams and crossbeams is proposed. The first overhead system is the overhead of line track. The longitudinal beams are arranged in a zigzag line parallel to the line, and the crossbeam is arranged perpendicularly to the line. The second overhead system serves as the basis of the first overhead system. The longitudinal beams are parallel to the frame bridge, and the crossbeam is arranged perpendicularly to the longitudinal beam, which are supported on support piles. In addition, the Bridge Doctor V4.4 is used to establish the finite element spatial model with a double overhead reinforcement system of longitudinal beams and crossbeams to calculate the stress state of this system. The results show that the stress and deflection of the longitudinal beams and crossbeams in the construction stage meet the requirements of the specification, which can realize the one-time overall overhead of small-radius curved railway lines and the horizontal overhead span reaches 13.8 m so as to avoid the conversion of support points in the overhead system and the secondary reinforcement of the frame bridge structure, improve the overall structure, and is successfully applied in actual engineering.
