Study On Seismic Response Of 600m Super-span Reinforced Concrete Arch Bridge

Earthquake taken place all over the world cause huge losses to human life and property. Bridge as the lifeline engineering, once damaged in the earthquake, it will bring serious obstacles to rescue and relief. Reinforced concrete arch bridge is suitable for construction in mountain area for its beautiful appearance, strong spanning capacity, low cost. So far, Wan Zhou Yangtze River Bridge located at Chongqing is still the biggest span reinforced concrete arch bridge in the world. Europe and the United States, Japan, China, etc have done explorative study on 600m-1000 m grade span reinforced concrete arch bridge.In this paper, 600 m reinforced concrete arch bridge as the research object, based on OpenSEES software to performed seismic studies and seismic response of performance:For trial design research of 600 m reinforced concrete arch bridge, the linear elastic finite element model, the material nonlinear model and geometric nonlinear model considering the material nonlinearity of bridge structure were established, and then comparative study on the dynamic characteristics of the three models was conducted; on this basis, 20 natural seismic waves under consistent excitation were applied to the structure for IDA analysis, calculation results of typical seismic waves on seismic response of the structure value were compared, studies have shown that the material nonlinearity and geometrical nonlinearity have great influence on the internal force and displacement response of 600 m reinforced concrete arch bridge. Considering the material nonlinearity, under portrait + vertical and landscape + vertical seismic action, Compared to the linear elastic finite element model, the biggest bending moment respectively increased by 44.1% and by 84.8%; considering geometric nonlinearity + material nonlinearity later, under Portrait + vertical and landscape + vertical seismic action, Compared to the material nonlinear model, the biggest bending moment respectively increase by 32.5% and by 4.4%.Considering the material nonlinearity and geometric nonlinearity, the effects of main arch ring steel consumption on anti-seismic property of the main arch ring under the seismic action were studied. Comparing and analyzing the internal force and displacement response of the main arch under Longitudinal-vertical and Lateral –vertical ground motions, results showed that the impact of in longitudinal reinforcement is not big before the main arch ring entering the nonlinear, it begin to rise after the main arch ring entering the nonlinear. And amount change of the stirrup has a great influence on the anti-seismic property of the main arch ring, the entrance of nonlinear lead to great changes on seismic peak acceleration.For beam bridge road, continuous beam- continuous frame system(Scheme A) and set the T junction pier structure continuous beam- continuous frame system(Scheme B) were adopted. Research seismic response analysis under different arrangement way beam span bridge considering material nonlinearity and geometrical nonlinear, internal force and displacement response in the seismic peak acceleration of 0.1 g, 0.4 g, 0.8 g and 1.2 g. by comparison and analysis, the reasonable solutions of A and B trail design can be acquired. On this basis, through analysis and comparison on design scheme, the optimal design scheme can be obtained.