The Research On The Overturning Stability And Supporting Optimization Of Single-point-supported Curved Girder Bridge

"Bending- Torsion" effect of Curved bridge making it has a great torsion deformation in the symmetric loads, under partial loads, the effect is more obvious. Especially for Single-point-supported curved girder bridge, its beam end torque is extremely large for the middle supports can't pass the torque, it will lead to lack of stability of such reserves bridge problems. Therefore, in the design process of Single-point-supported curved girder bridge, how to improve the mechanical state and improve the stability of the structure is the primary problem. Furthermore, the supporting optimization can effectively improve the mechanical state of such a bridge abutment. Based on the basis of the existing theory, the main factors affecting curved bridge with characteristics are analyzed by numerical simulation method, and supporting optimization of single-point-supported curved girder bridge is of in-depth research. The dissertation mainly completes the research in the following aspects:(1)Expounded the application and engineering accident general situation of curved girder, further put forward the existing problems of single-point-supported curved girder bridge;(2)By establishing the equilibrium equations, the theoretical geometric equations and the derivation of the relationship between internal forces and deformation of micro-beams, three equilibrium differential equations expressed in displacement component are deduced. Further indicates that the main factors affecting structure characteristics;(3) By establishing the finite element model of straight girder and curved girder with the same span combination, indicates that the unique mechanical characteristics of curved girder through their comparison of internal force, deformation and reaction force. Through the relevant introduction of resistive overturning stability checking basis and the comparison of checking method, finally a safer checking method is received.(4) By setting the radius of curvature and the diaphragm number as a parameter, changing its values, studied the influence of them to the structure characteristics. Finally discusses the influence on structure resistive overturning stability(5) Introduced the commonly used three kinds of Supporting methods, compared the influence on structure characteristics and overturning stability with them.(6) The principle and method to adjust torsion through presetting decentration of support abutment is introduced. By setting the presetting decentration and the end bearing transverse spacing as parameters, changing their values, and analyzed the influence on the superstructure and overturning stability of Single-point-supported curved girder bridge. Finally the principle of determining supporting optimization goal with Single-point-supported curved girder bridge for various radius is deduced.