Affecting Factors On Shear Center Of The Curved Continuance Rigid Frame Bridge

In recent years, with the city flyovers and highways, particularly the large-scale construction of mountain highway development, curved bridge because of its good will to overcome the topography, landscape, or to limit the road alignment, and to reflect the building Investment in the economy, mechanics, the perfect combination of aesthetics and are widely used. The construction of Long-span prestressed concrete curved rigid frame Bridges are more and more used. Compare with a straight rigid frame Bridge, because of bending and torsion coupling, the curve rigid frame Bridge for the forces and deformations has a significant of the space, the existence of horizontal and transverse moment to deformation, making the beam of internal forces and deformation of more complex.The method of calculation and analysis theory of Continuous curved box-girder bridge is not under 10 methods, the current development of the theory is: Pure Twisting Theory and Constraint Twisting Theory by the theory of analytical method. Many researches that based at Vlasov Differential Equation are guided by applied only to the invariable cross section of curved beam differential equation. The Vlasov Differential Equations is established under the assumption that, assuming that heart-shaped cross section and the shear center is coincidence. Although the results are consistent with the actual. However, in practical engineering of commonly used thin-walled beam, the curved beam of its own characteristics forces that determined the type of the section it is very difficult to meet the above assumption.The position of the torsion center is an important geometric parameter of box girder , and it plays a significant part in the calculation of torsion displacement and internal force for thin-walled box girder bridges . The Shear center is Of the inherent cross-section of the geometric properties, it is from cross-section of the decision by the geometric shape. This article to Yin Shui Gou Bridge as the background mainly use MIDAS software of finite element, respectively Changes were made on different factors in the prestressed concrete curved for a modeling analysis in order to verify that the Vlasov differential equation assumption is universal. Through a certain key function in the software show a different cross-section characteristics value and make a comparative analysis by changing the values of the following factors: curve radius, box-girder beam height, box-girder bottom slab thickness, box-girder web slab thickness and top width of the cross section ,and measure the impact effects upon the shear center location, and then make a proper analysis of the distance between heart-shaped cross section and shear centre which can be drawn on it the factor with the biggest affection.