The Space Mechanical Analysis On Curved Continuous Rigid Frame Bridge

With the rapid development of mountain expressway and elevated road, the curved continuous rigid frame bridge has been widely expanded in recent years. Because it can be well adapted too the topography constraints, reduce road length, make the road smoother, fluid, and have other distinctive advantages it has been widely used in highway and urban overpass in these years. Meanwhile, there are some problems exist in curved bridges, such as: the influence of temperature and prestress reinforcement. The bridge of NiXiGou 2# is taken as the research object to research the influence of the temperature and the prestress reinforcement with the help of FEM software Midas FEA.Firstly, summarized the load-carrying capability characteristic and research present status of curved bridge. I have discussed the fundamental theories of curved bridge including deducing the differential formula, the method that can solve the question of Shear Lag Effect and the torsion theory.Secondly, considering the effect of prestressed steel beam on curved girder bridge ,this paper discussed the action principle of Prestressed steel beams on concrete box girder and derived the curved girder bridge prestressed equilibrium differential equations. Based on the actual project, using the finite element method, the artificial models which have different curve radius are built: 800m, 1500m, curves and straight-line continuous rigid frame bridge. Through the discussion of the calculation results, I obtained the important conclusion that during the process of construction the roof prestressed beam has a significant impact and in the process of the bridge into a state, the cross-floor beams have a significant impact on the curve rigid frame bridge deformation and stress, also.Finally, considering the effect of the temperature on the curved bridges, this paper summarized the study of curved girder temperature effect and the rules of some countries about temperature loads. According to the local meteorological data, I studied the reactions of the curved continuous rigid frame bridge with different curve radius and concluded the regulation caused by sunshine temperature and year temperature. The laws which are put forward in this article are very important for the designers who design the same type of bridges.