Study on dynamic characteristics of reclining arch bridges

reclining arch bridges;  finite element method;  frequency;  Mode shape

Zhanhe Bridge, Chengdonghe Road, Pingdingshan City, is a reclining reinforced concrete box rib arch bridge, the inner arch of the bridge is tilted outward, the outer arch is tilted inward, and the combined arch rib is combined with tie beam and beam to form a spatial structure system. This bridge type is rare, and in order to understand the dynamic performance of this bridge type, it is necessary to analyze the spatial dynamic characteristics of the bridge. ANSYS software was used to establish the finite element calculation model of the bridge, and the vibration period and mode shape of the bridge in the first 15 steps were calculated. The calculation results show that the stiffness inside and outside the arch rib surface of this bridge type is quite different, the lateral stiffness is weaker than the vertical stiffness, and the lower level of the bridge is dominated by the lateral vibration of the arch rib. The self-vibration period of the bridge is large; The bridge mode shape is relatively dense.