Theoretical Study On Accordion Effect Of Composite Box Girder With Corrugated Steel Webs

Corrugated steel webs can be freely telescopic along the longitudinal direction of the bridge because of the accordion effect. Corrugated steel webs have high shear strength and the bending effect is mostly considered not exist. ANSYS software simulation and theoretical analysis is adopted in this paper, on accordion effect of composite box girder with corrugated steel webs were more detailed study, the main work and research conclusions are as follows:(1) ANSYS finite element simulation are used to different materials(concrete, flat plate, corrugated steel) of Jane supported box girder. The ANSYS to simulate the deflection, the deflection theory calculation results and existing experimental results compared to prove the reliability of finite element model;(2) Effective elastic modulus of corrugated steel web model was analyzed theoretically, and with the three different web(concrete, flat plate and a corrugated steel webs) box girder model which are combined with the axial force analysis of the lower abdominal plate at the same level of axial force. It shows that the axial stiffness of corrugated steel web is very small, and the ratio of horizontal axial force is small, so it can hardly resist horizontal axial force.(3) The finite element analysis and theoretical analysis of the top plate and bottom plate under the action of longitudinal bending moment are carried out on the box girder with three different web plates, It shows that the simplified model of the section of corrugated steel webs in the theoretical analysis is right. It is further illustrated that the corrugated steel web plate due to the accordion effect along the longitudinal direction of the bridge basically does not resist bending moment.(4) Compared with shear comparison of theoretical performance calculation and finite element simulation analysis on the above three different web of simply supported box girder model, it is proved that in the box girder with corrugated steel web box beam, under the concrete slab on shear contribution is negligible.(5) Under three different load conditions(pure bending, approximate pure shear and symmetrical concentrated load), the influence of geometric parameters of corrugated steel webs on the mechanical properties of corrugated steel webs was compared and analyzed. It is proved that the shear behavior of corrugated steel webs will decreases with the length of the straight steel webs increasing, but will increases with the bending angle increasing,normal stress and shear stress are increased with the increase of the thickness of corrugated steel webs decreases gradually.