Seismic Response Analysis And Dynamic Characteristics Of Deck Type Concrete Filled Steel Tubular Arch Bridge

The development of concrete filled steel tube composite materials has a long-standing history.In the early 20th century,the Soviet Union built the world's first concrete filled steel tube arch bridge in Siberia,It was a 140m upper arch bridge.At the end of the 20th century,China built the first concrete filled steel tube arch bridge in Sichuan.It was a 110m down-supported tied arch bridge.With the advancement of technology and people's constant exploration,Concrete filled steel tube arch bridges are widely used on roads and railways.Earthquake disasters have brought painful lessons to our country.The 7.8-magnitude earthquake in Tangshan in 1976 and the Wenchuan magnitude 8.0 earthquake in 2008,They are relatively large earthquake disasters in China in recent decades.The earthquake not only caused great damage to the local area,It also caused local people to be displaced and the country's economic losses were irreparable.Experts in the international professional field pay great attention to the study of seismic resistance of bridges.This paper takes the Tangjiahe Bridge of Guzhang Expressway of Zhanghua Expressway as the research background,and The dynamic characteristics and seismic response of the bridge were calculated using the software Midas/Civil 2015,The main contents are as follows:(1)The development of arch bridges and the development of concrete-filled steel tubular arch bridges,the characteristics of concrete and steel pipe composite materials and the research status of seismic analysis of arch bridges are introduced.(2)Describes the methods of earthquake disaster and seismic theory analysis,The development and basic theories of elastic static method,response spectrum method and dynamic time history method are listed.(3)A detailed divisional introduction was made to the engineering overview of the bridge,and a finite element model was established.The calculation theory of the self-vibration characteristics of the bridge is expounded,Then analyzed its mode shape and frequency.Finally,the influence of the arrangement of the transverse bracing and the change of the boundary conditions of the main beam on the natural vibration characteristics is discussed.(4)The response spectrum analysis of the bridge was carried out,and the calculation results of the two forms of cross bracing arrangement were compared,Then discuss its impact on seismic response.Finally,the influence of the boundary conditions of the main beam on the seismic response is discussed.(5)The bridge was analyzed by time history and the characteristics of the bridge under earthquake action were analyzed.(6)Summarize the conclusions of the calculation of the bridge,Insufficient in the content of this paper and the need to further explore.