Standardized Design And Mechanical Properties Analysis Of Prefabricated Railway Continuous Beam Bridge With Corrugated Steel Webs

As a new type of bridge structure,prestressed concrete(PC)box girder with corrugated steel web(CSW)combines the advantages of concrete and steel.and it has been widely used in highway bridges.Howver,it is rarely used in railways.In this thesis,a continuous PC composite box girder of railway with CSW was designed based on the(40 + 64 + 40)m PC continuous box girder bridge.The deflection,shear lag effect and buckling behavior of the newly designed CSW bridge were analyzed.The main research contents and conclusions of the dissertation are summarized as follows:1.A prefabricated construction scheme which is applicable to the CSW bridge was designed.The static performance between the composite box girder bridge with CSW and the PC continuous box girder bridge were compared.The mechanical properties of the CSW bridge met the codes according to the results,.2.The formula for deflection of the composite box girder with CSW and variable cross-section in cantilever state is derived using equivalent section stiffness method and Simpson formula,and the results of the formula was compared with finite element analysis.3.The shear lag effect of the composite box girder with CSW was analyzed,and the results was compared with that of the PC continuous box girder.It shows that the maximum shear lag coefficients of the two kinds of box girders have the same distribution pattern along the longitudinal direction of the bridge due to different load cases.At the most unfavorable sections of the shear lag effect,the maximum shear lag coefficient of the composite box girder with CSW at the top plate is larger than that of the PC continuous box girder but smaller than that of the PC continuous box girder at the bottom plate.The variation of the effective width ratio with width span ratio of the composite box girder of railway with CSW was studied,and the formula of the effective width ratio of the critical section was fitted according to the results.4.The shear buckling behavior of CSW was studied,and the geometric factors affecting the shear buckling of CSW were analyzed by considering the influence of double nonlinearity and initial defect.The results show that the stability of CSW is positively correlated with the thickness and the bending angle of inclined plate but negatively correlated with the beam height.When the wave height is too large or too small,the stability of CSW will decrease.In addition,the stability of CSW is closely related to the length of inclined plate.When the inclined plate is too long,the stability of CSW decreases,and the failure mode of CSW is local buckling of the inclined plate.