Research purposes: Taking the continuous beam-arch combined structure of the Yazi River Bridge in 56+116+56m of the Chengdu-Mianyang-Leshan Passenger Dedicated Line as the research background, the researches were done in detail on the beam-arch combined structure,including the conformation,loading features of hanger rod and abutment layout,and the introduction was given to the structure features of the beam-arch combined structure, including the establishment of the model, determination of the loading, calculation of the beam arch and hinger rod and analysis of the dynamic characteristics and the arch base for providing the reference to the similar works.
Research conclusions: The continuous beam-arch combined structure has the merits of both long - span continuous beam and arch. Combined with the same large span continuous beam, the height of the main beam can be lowered because of the arch effect. The pressure-resistant and deformation-resistant capacities of the concrete are much enhanced because of the hooping effect of the steel tube on the concrete. The stability of the steel tube is improved because of the concrete in the steel tube to make the arch and beam being able to bear the loads. So the beam-arch combined structure has the features of the good capacity of bearing load,the good stiffness of the structure,less height of architecture and mature construction methods, and this type of bridge will become one of the most competitive bridges.