Mechanical Behave Analysis Of The Small-radius Bridge

With the rapid development of urban roads, in order to obey the plane linear arrangement and improve the transportation hub of use features, curve beam bridge has been widely used, the type of the overpass has becomes an indispensable part of urban road network. As the curve radius bridge's curvature decreasing, The mechanical behave of small-radius curve box girder bridge becomes more and more complex, in view of this, it need further mechanical behave research to a small-radius curve box girder bridge. This article includes the following:1. The preliminary analysis of the mechanical behave to small-radius curve box girder bridge; for different curved bridge, analysis and compare theoretical calculations of mechanical behave of the curved bridge, and sums up the scope and calculation of theoretical advantages and disadvantages, the study focus on the beam grid method in the analysis of curved box girder.2.The research in the backgroud of Suifenhe tongtian road small-radius curve box girder bridge, ues the method of space grillage, with bridge structural analysis software for simulation of real bridge, from the curvature radius, diaphragm beam, section forms of the main beam, the distence of supports, ratio of bending and torsion stiffness, central angle, the ratio of beam width and curvature radius and supporting forms and so on, for small-radius curve box girder bridge's vertical bending moment, torque, vertical shear strength, deflection and support reactions and other properties of the force carried out a detailed analysis.3. In order to study small-radius curve box girder bridge's mechanical behave, make a load test to Suifenhe tongtian road small-radius curve box girder bridge, sub-eight kinds of conditions on the small-radius curve of the strain, deflection and bearing deflection studies, throught analysis and compare the measured data and the theoretical data, get the mechanical behave law of the small-radius curve box beam bridges.The results show that:the ratio of bridge width and curvature radius is the greatest influence to longitudinal bending moment; central angle is the greatest influence to against torsion; section form is the greatest influence to the vertical shear; we can throught increase the radius of curvature, setting pier top diaphragm, increase box room, increase the distence of supports, satisfy the premise of the bending moment of inertia used to increase against torsion moment;reduce the central angle, decrease the ratio of width and curvature radius, set double supports way to increase the against torsion behave to the small-radius curve box girder bridge, reduce the "Bending-Torsion" Coupling behave. But, the different degrees on the longitudinal bending moment and vertical shear. Using single column pier, the pier top with vase-like,and use double-supports, can greatly enhance the against torsion behave of the small-radius curve box girder bridge.