Design Theory And Engineering Application Of Curved Girder Bridges

With the development of urban road and highroad traffic, the curved girders are increasingly widely applied and become an important bridge style in modern communication engineering. But the　content　of　using　bridge　criterion　have　lagged　behind　the　development　of　bridge,　can't　guide　the　design　of curved girders, there are some difficulties with　designing　curved girders.　In　this　paper,　the　research　on　some　problems　of　the　design　of　curved　girders　has　been　carried　on.　It　has　some　practicality in engineering.　A curved girder is a spacial structure under the coupled actions of bending and torsion, so planar analysis isn't applicable for it. In this thesis, based on the thinned wall theory of Volasov's and the engineering practice application, the analysis theory of continuous curved girder bridge and the frequently used analysis methods in engineering are introduced and concluded. The　mechanics characteristic of structure load has been studied, with coupled effect of bending and torsion, unbalanced force on inner beam and outer beam, and the effect of dead load and live load. It give some advices about compute model of curved girder bridge, the choice of compute program, and the design progress. Some problem such as the choice of section and path, compute　analysis, supporting restriction, bearing eccentricity in advance and generally collocation of curved girder bridge are discussed. It bring forward some theory that the reason casing the outward displacement along radial direction of curved bridges is temperature, and the mostly measure solving the motion is selecting rational supporting restriction. It also bring forward that the key factor affect the magnitude of internal force in beam is the size of curved girder bridges' radius,　central angle to every span. the span is selected based on curve radius to assure the structure reasonable and economy. Finally, based on two practical project, the design method of curved girder bridges and the key problem with it are discussed, and it is analysed and compared to the characteristic of different supporting restriction.