Analysis Of The Shear Lag Effect In Curved Continuous Box-girder Bridge And The Research On Practical Calculating Method

The shear lag effect can't be ignored in the design of curved box-girder bridges with wide flange and small span. Due to curvature, the curved box-girder bridges have more complex stress distribution in the section; it is difficult to calculate its effective width. In order to come up with a method to calculate the effective width which is fit for curved box-girder bridges, it needs to research the laws of the shear lag effect. This paper uses large general finite element program ANSYS to analyze the shear lag effect in curved box-girder bridges. It confirms element that named three-dimensional-degenerated shell element as the modeling element; creates a finite element model of three-span continuous curved box-girder bridge; calculates the transverse and longitudinal shear lag coefficient; uses program ORIGIN to make simulations. The rules of transverse and longitudinal shear lag coefficients of continuous curved box-girder bridge are summarized. On the basis of present research, analyses the influences of structure parameter to shear lag effect such as radius of curvature, width-to-span ratio. At last, applicable calculation formulas of curved box-girder were made,in which the curved box-girder bridges are divided into some sorts by their radius of curvature and width-to-span ratio.