The Research On Force Of The Curved Bridge With Small Radius Big Span

Along with the rapid development of transportation in our country,the curved beam bridges have generally appeared in the highway,high-speed railway,urban expressway,and other various grades of bridge engineering.Due to some mechanical properties of its own,the stress of the curved beam bridge is much more complicated than straight bridge.In practical engineering was also seen to master is not comprehensive and lead to stress its collapse,causing casualties and huge property losses.Therefore,the domestic and foreign scholars have conducted a lot of research,however,the current domestic design specifications of curved beam bridge has no special guidelines.When the designers are designing curved beam bridge,they almost refer to the design of straight bridge.It may be feasible for those curved beam bridges with longer radius of curvature,however,considering the problems arising in the used curved beam bridges,this design doesn't conform to the force bearing feature of those curved beam bridges with shorter radius of curvature.Therefore,the curved beam bridge analysis and study of mechanical performance,can be more comprehensive,accurately grasp its stress state,which has practical sense in design and construction.Through broad access and organize documents,papers on the development situation and mechanical characteristics of curved beam bridge are introduced,the analysis theory and analysis method on the curved girder bridges are elaborated,key points of design of curved beam bridge are summarized in detail in this paper.Taking a prestressed concrete continuous curved beam bridge as the object,respectively compared finite element model with single beam method and beam grid method.The effects of different working conditions on the support reaction and the bending moment are studied.Also,some related transformation rules are obtained.In addition,in order to verify the correctness of the calculation results and provide reference for the design of similar bridges,the indoor model load test is carried out,calculation results and test results are compare,the validity of the calculation model is teste,the actual working condition of the model bridge is evaluated.This thesis is based on an actual bridge project with the span of 3×40m,and the obtained experiment result basically conforms to the theory result,as follows:(1)Under the effect of dead load and live load,Single Beam Theory can be applied in the displacement calculation analysis of actual curved beam design.(2)Under the effect of dead load and live load,Single Beam Theory can be applied in the support reaction calculation analysis of actual curved beam design.(3)Under the effect of dead load and live load,the distortion calculated by Single Beam Method can't truly reflect the distortion's lateral distribution condition in curved beam design,so more accurate Beam Grid Method or Substantial Finite Element Method should be used to make calculation and analysis.