The Seismic Response Analysis Of Arch Bridge CFST

Earthquake is more in our country, especially since the Wenchuan earthquake, in Yushu earthquake, ya, country and strengthening the research o f seismic fortification. Earthquake often brings serious economic losses, caused by structure and severe damage to structures. As once the bridge is damaged in transportation engineering, want to in a short period of time is very difficult to repair, delay the subsequent rescue and relief work, produce secondary disasters, aggravating the situation. Concrete filled steel tubular(CFST) arch bridge in our country, a large number of construction, also is the future development trend of the arch bridge, the dynamic characteristics and seismic performance analysis and research is particularly important.Though more studies on the seismic performance of arch bridge, but the research on seismic performance of concrete-filled steel tube concrete arc bridge is less. This article summarizes the common forms of damage, bridge structure home and abroad are introduced about the development of the arch bridge, steel tube concrete arch bridge with the characteristics and the seismic research present situation. This paper introduces the current main methods of several kinds of a seismic calculation and analysis. Established the calculation model of the space finite element analysis of Bridges, and made the first ten frequencies and modal analysis. Respectively by using response spectrum method, the input of the E1 and E2 acceleration spectrum curve, and consider only in transverse to the bridge, only in the bridge to and only under the effect of the vertical of the seismic response of the structure of the bridge. Choose Taft seismic wave, using time history analysis method, considering only only in transverse, longitudinal and only in the vertical seismic wave E1 and E2 respectively under the action of earthquake response. Comparison and analysis the E1 and E2 earthquake under the action of the acceleration response spectrum and Taft seismic wave under the action of E1 and E2 earthquake time history analysis of the calculation results. It is concluded that under the horizontal earthquake excitation, arch rib mainly lateral movement. Basic does not affect the lateral seismic vertical and longitudinal displacement. Arch foot arch rib axial force is bigger, should pay attention to the strength of the this part. Longitudinal seismic excitation, the arch rib is mainly produce longitudinal motion and the vertical movement. The location of the maximal displacement occurred in about a quarter dome. My and arch rib of arch rib Fx is larger, at the bottom of the pier Fx and My value is also bigger. Vertical seismic excitation, the arch rib of Fx is opposite bigger, but the displacement of arch rib value is smaller, My and Fx larger piers. Both response spectrum and seismic excitation, the displacement of the arch rib or axial force, shearing force, torque, bending moment is roughly symmetric. Response spectrum and time history analysis results of the two can check each other, analysis of response spectrum method and time history analysis of data, found that almost the same change rule, but still part of the internal force difference is bigger. This bridge analysis results, transverse displacement of arch rib, the schedule is slightly less than a response spectrum analysis of numerical results. The remaining displacement, the schedule is slightly greater than the response spectrum analysis of numerical results. For internal force, the response spectrum analysis of slightly less than the time history analysis values.In a similar this kind of bridge design and calculation of different direction seismic action or very be necessary. Another respon se spectrum analysis and time history analysis at the same time is also necessary, can be compared each other, check each other. Negative value for bridge seismic design, thus to strengthen a seismic measures, improve the seismic resistance of Bridges, ach ieve good social and economic benefits.Finally, illustrates some this article consider not considerate and insufficient place. At the same time puts forward some need further research and discussion on the problem.