The Shear Strength And Experimental Study Of Girders With Corrugated Steel Webs

The prestressed concrete composite girder bridge with corrugated steel webs is a new type of bridge structure which has been widely applied in domestic in the past ten years.Due to the mechanical properties of the prestressed concrete composite girder with corrugated steel webs,the calculation of shear strength of corrugated steel webs is an important issue in the shear design of the prestressed concrete composite girder with corrugated steel webs.In this paper,the elastic shear buckling strength and ultimate shear bearing capacity calculation methods for corrugated steel webs were analyzed and studied.Due to the mechanical properties,the ultimate shear bearing capacity of the beam with corrugated steel webs is closely related to the shear strength,and the shear buckling strength is significantly affect the shear strength.The theoretical formulas for local elastic shear buckling strength and global elastic shear buckling strength of the corrugated steel webs were summarized,and analyzed the empirical calculation formulas for interactive elastic shear buckling strength.Based on the theoretical calculation formulas,the shear buckling analysis of the Qian Shan River Bridge was analyzed,and the relevant sections were checked.Five I-shaped steel beams with different longitudinal stiffeners were conducted static experiment to collect strain and deflection to compare with finite analysis.The results showed that the finite element and experiment were well matched.By theoretical analysis,the longitudinal stiffeners can effectively reduce the web height so as to improve its ability to resist buckling.The buckling form of steel beams with different longitudinal stiffeners is related to the stiffness of the stiffeners and the stiffness of the plate.If the stiffness ratio about the stiffeners and the plate beam is bigger than the limit of the ratio,the stiffeners buckling will not happen and the buckling occurs in the webs such as simply supported boundary.When setting up the stiffeners,it is necessary to consider the stiffness of the plate to prevent stiffeners buckling,and buckling occurred in the corrugated steel webs to improve its buckling strength.With the span of the prestressed concrete composite girder bridge with corrugated steel webs increasing,the corrugated steel webs are more and more high,it is necessary to study the type 2400 corrugated steel webs buckling stability.On the basis of a reliable shear buckling analysis results about the corrugated steel webs,the formulas about local elastic shear buckling strength and global elastic shear buckling strength of the type 2400 corrugated steel webs were corrected related to geometric parameters of the webs height and thickness.Through the interactive elastic shear buckling strength formulas,and should be controlled ?s?0.6,the shear stress of steel webs under shear load is lower than the allowable shear buckling stress of steel and the buckling of the corrugated steel webs will not occur.Under the design which controlled by shear buckling strength,it can give full using of steel strength.