The Correlation Research On Structure Design And Analysis For Heterotype Steel Truss Bridge

With the rapid development of China's economy and the continuous increase of steel production,steel truss bridge is widely applied in highway and municipal field due to its advantages of light structure,large bearing capacity,high speed,short construction period,beautiful and so on.This paper take Simapo bridge as engineering background,based on the basic form of the classic steel truss girders,innovative put forward a new kind of long-span steel truss bridge: "herringbone" triangle structure form,and take deep research on the sides of design principles,design concepts,structural features and so on.Secondly,by using the large finite element analysis software Midas/Civil,the stress and deformation characteristics of main truss,beam and longitudinal beam under different load condition combination are obtained.Then,according to the stress analysis results,the stress tests are performed on the structural components.At the same time,buckling analysis results show that the stability of the structure is good.Then,based on the established finite element analysis model,the dynamic characteristics of the structure are analyzed,obtained the basic mode and frequency of the structure.And the influence of dead load on structure dynamic characteristics are studied,the research results show that the improvement of dead load ratio for Simapo bridge has great influence on the natural frequency,it can greatly reduce the natural frequency of bridge.In addition,on the basis of wind tunnel test data,this article establish a bridge three-dimensional time-domain load model,and based on the modal superposition theory,analyzed the wind-induced vibration characteristics of counteracting force,node displacement and member internal force,provides a useful reference for analysis of the same kind of bridge structure.