Study on Natural Vibration and Nonlinear Seismic Response of CFT Arch Bridge Constructed in China

Using CFT structure into arch rib of arch bridge is rational since CFT is resistant to the axial compressive force. In Japan, the first CFT arch bridge-the Second Saikai Bridge-is under the erection. In the meantime, the seismic safety of civil engineering structures is severely required. Therefore, the seismic safety of CFT arch bridges against strong earthquakes must be grasped. In this paper，the Jianghan Wuqiao Bridges，which is a CFT bridge in China and has the same span with the Second Saikai Bridge, is made to be the analysis object and the differences of natural vibration properties between these two bridges are discussed. Furthermore, the nonlinear seismic response properties of the Jianghan Wuquiao Bridge are discussed

Study on Dynamic Properties of Partially Concrete Filled Steel Tubular Arch Bridge

Concrete Filled Steel Tubular (CFT) arch bridges are excellent in strength under in-plane load. However, they are not always excellent in seismic safety under out-of plane seismic load. A partial CFT arch bridge may be useful to improve seismic safety. In this paper, the dynamic properties of the partial CFT arch bridge are discussed by using the existing partial CFT arch bridge built in China (Sanqian Bridge). Firstly, the validity of analytical model is examined by ambient vibration test of this bridge and vibration experiment using moving vehicle. Then，by changing the concrete filled length，the effect of the filled length on the natural frequencies and earthquake response is discussed