Abstract:Abstract:Research purposes: A single arch ril) prestressed concrete beam arch combination bridge was studied. The prestressed concrete beam and arch bridge will be two kinds of structure system organically unifies in together,which has the advantages with a big stiffness,low construction height,and attractive appearance,but this kind of structure for multiple statically indeterminate structure,mechanical performance is complex,the design is difficult. The research was made in this paper to reveal its mechanical characteristics. Research conclusions :( 1) The arch and beam combination bridge bears loads togetlier,which include compression of arch rib,and tension of girder,the interaction of the balance system, greatly reduces the arch and beam bending moment,uniforms beam stress,the static and dynamic performance and the operational performance of structure are better. (2) Girder adopt rigid collar beam and arch rib truss type,increasing the structure stiffness and bearing capacity, improve the structure of spanning capacity,through the optimization of arch rib and girder stiffness ratio,can further reduce the girder structure of t!ie building height. ( 3 ) When bridge crossing design,building height is constrained,and the class construction girder bridges by pushing,after pushing in place on the main girder of assembling the construction method of the single rib,greatly reduce the construction process and the late maintenance and repair of the busy traffic impact under t!ie bridge. (4 ) The conclusion could be used for design,calculation and analys of single arch hId beam arch combination bridge.