Research On The Upper Structure Checking Method Of The Existing Double-Curved Arch Bridges

Double-curved arch bridge is widely used in the short and middle span bridges in China. This paper takes the double-curved arch bridge as research object; mainly research several problems on how to examine the upper structure of the existing double-curved arch bridges. In the process of checking the upper structure of the existing double-curved arch bridges,the joint action of main arch and spandrel structure and the load transverse distribution of main arch are key contents. After studying existed literature of theoretical and experimental research, this paper carries through an in-depth study use the Finite element method, and suggests the corresponding checking method and Finite element models considering certain distress of the upper structure. Research indicates that the joint action of main arch and spandrel structure is notable for the bending moment and deformation to existing double-curved arch bridges; the ends of columns can't be simulated as pin-connection. The joint action of main arch and spandrel structure should be counted even when side spandrel arch rings have been cracked; Two-hinged arch would be used to simulate the cracked spandrel arch rings.It is proved that load transverse distribution in double-curved arch bridges exists abjectly, the load transverse distribution should be counted in the checking calculation. For narrow double-curved arch bridges, eccentric compressive method is suggested; for wider ones, extensive G-M method is suggested. The load transverse distribution in wide bridges should be calculated separately in arch top section and L/4 section, and the load transverse distribution of the arch foot section can be approximately equal to that of arch top section or L/4 section.