Static And Seismic Response Analysis Of Steel-Concrete Composite PC Continuous Rigid Frame Bridge

With the wider application of prestressed concrete in bridge structure,the span of bridge is gradually increasing.While the span of the prestressed concrete continuous rigid frame bridge increases,there are many diseases in the bridge structure.For example,the deflection in the middle of the span increases with the increase of the span,and the cracking of the floor and web is unavoidable.In view of this situation,structural designers have developed a new type of steel-concrete composite structure on the basis of traditional materials and structures.The application of this structure in continuous steel bridge is to replace the web of concrete material with corrugated steel plate.Compared with the traditional prestressed concrete continuous rigid frame bridge,this design makes the weight of the main girder structure much smaller and makes it more steel-bonded.Compared with the constructed bridges,the steel consumption is greatly reduced and the durability of the structure is increased.This type of bridge has a very good applicability and development prospects.Many countries in the world have achieved fairly good development,including France and Japan,where the development is very rapid.From the initial simple-supported beam to the uniform cross-section box girder and then to the final variable cross-section box girder,large-span continuous rigid frame bridges not only confined to the development of appearance,but also have a better development in the structural system.From the research results of this kind of steel-concrete composite structure in recent years,it can be known that the use of this kind of steel-concrete composite structure in long-span bridges reduces the weight of the structure itself,because there is a certain relationship between the quality of the structure and the stiffness of the structure.Based on this situation,the dynamic characteristics of the structure itself will be affected,and the response effect of the structure under earthquake action will be weakened.As a result,it is very meaningful to study the structure under earthquake.The concrete research work of PC continuous rigid frame bridge with corrugated steel webs is as follows:(1)At the beginning of this paper,the development history of this steel-concrete composite structure is introduced in detail,and the research results of some experts and scholars at home and abroad are elaborated and summarized.The development status of corrugated steel webs continuous rigid frame bridge at home and abroad is summarized,and the main contents of this paper are put forward.(2)Aiming at the analysis of dynamic characteristics of bridge structures,the method and dynamic equation of dynamic characteristics analysis of bridge structures are proposed based on the theory of finite element structure.The theoretical expatiation and research are carried out from three aspects of mass,stiffness and damping,and their formulas are deduced and demonstrated in detail.Combining with the dynamic characteristic vibration equation of steel web box girder bridge,the theoretical basis for the dynamic vibration equation of corrugated steel web continuous rigid frame bridge is provided.The dynamic characteristic vibration equation is elaborated from three aspects: external prestressing,shear deformation and shear lag effect.(3)In the follow-up work of this paper,the static situation of the whole bridge structure is analyzed and compared in detail,and the theoretical development process of response spectrum and time history analysis method is also introduced in detail.The response spectrum and dynamic time history analysis of the centipede River Bridge under the two design schemes are carried out respectively.Finally,the analysis results under response spectrum method and dynamic time history analysis method are carried out.By comparison,we can know the rationality of the seismic design analysis of the centipede River bridge.