| The corrugated steel webs composite girder bridge is a new type of steel-concrete composite structure bridge which replaces the traditional box girder concrete webs with corrugated steel webs.With the increase of the span of this bridge type,the shear buckling problem of the section near the root of corrugated steel webs is more prominent.It is a good structural measure to strengthen the shear resistance of corrugated steel webs by lining concrete locally.In this paper,the force transfer mechanism and design of concrete composite webs lining of corrugated steel webs composite girder bridges with variable cross-section are studied.The main research work and achievements are as follows:1.Aiming at the scale loading test model of double cantilever composite beams,the finite element analysis is carried out.The shear stress distribution and shear force distribution ratio of corrugated steel webs and corrugated steel webs with lining are compared,and the influence of concrete with or without lining on flexural performance,stiffness,shear stress distribution and shear force distribution is studied..2.The analytical formulas of shearing stress for composite beams with corrugated steel webs with variable cross-section lined concrete considering axial force,shear force,bending moment and axially distributed loads are derived.The correctness and applicability of the formulas are verified by the finite element method and experimental data.The influence of axial force,bending moment and axially distributed load on the shear stress of beam section is studied by using the analytic formula.The influence of variable cross-section parameters on the shear stress distribution and the change of shear ratio is analyzed.3.Based on a practical bridge structure,a finite element parameter analysis model is established to analyze the influence of different lining lengths on shear stress,deflection and buckling stability.Suggestions for reasonable setting of length and thickness are given,and the calculation method for deflection and buckling of composite beams under the influence of lining is given.4.On the basis of the above research,the related design suggestions for the shearing resistance design of composite web are put forward. |
