Research On Seismic Performance Of Corrugated Sheet Web Plate Pc Combined Box Crossbeam Of Tower Of Suspension Bridge

Because of the suspension bridge has excellent crossing ability,it has become the most competitive bridge in the highway design in mountain areas and highly seismic regions.However,the weight and rigidity of the traditional PC beam bridge tower are relatively large,under the action of seismic load bridge tower prone to damage,In particular,the shear strength resistance of beams is not easy to pass.PC Box Girder with Corrugated Steel Webs has the advantages of light weight,small stiffness and the behavior of hig shear bearing capacity,the internal force response under seismic load is small,which is more consistent with the stress demand of bridge tower in highly seismic regions.At present,there had only a little research in this field,so it is necessary to study the loading characteristics of the structure under seismic load,this dissertation has carried on the discussion and the research in this aspect,the concrete research content and the achievement are as follows:Take a single span steel truss girder suspension bridge as the target of study,On the basis of considering the connection between stiffening girder and bridge tower,interaction between pile and soil established a finite element model.Developed 2 beams,3 beams,4 beams of the three-different beam program,each program is divided into PC beam and P C Box Girder with Corrugated Steel Webs.Calculation of Internal Force Response of Bridges in Seismic Loads by Time-history Analysis function.Choose the best 3 beam program,Application of section seismic analysis software XTRACT analysis of the yield moment of the upper,middle and lower beam of the bridge tower,Comparative analysis ultimate load of the bridge tower betwen PC beam and P C Box Girder with Corrugated Steel Webs.6 finite element model for different roof and baseplate thickness and different wide span ratio were established by ANSYS.Analysis the size and distribution of shear lag coefficient and to konw the influence of geometric structure on P C Box Girder with Corrugated Steel Webs through comparative analyses.Combined with the strain gauge test data from construction site to check the finite element calculation results.The results of the calculation show that,Under the same seismic load,bridge tower with P C Box Girder with Corrugated Steel Webs's most unfavorable moment and shear are significantly less than the results of bridge tower with PC beam.With the increase in the number of bridge towers beam,the most unfavorable moment and shear force of the middle beam and lower beam show a tendency to increase gradually,the most unfavorable moment and shear force of the upper beam show a tendency to decrease gradually,With the linear increase in seismic load,the bridge tower,the internal force distribution changed.P C Box Girder with Corrugated Steel Webs relative to PC beam can improve the initial failure of the bridge tower load intensity,effectively improve the ultimate bearing capacity of the bridge.As the roof and floor of P C Box Girder with Corrugated Steel Webs becomes thicker,the shear lag effect curve is more and more average,the shear lag coefficient of the outer web region increases rapidly with the increase of the beam width,the shear lag coefficient of the inner web region decreases as the beam width increases.