Transverse Force Analysis On Prestressed Concrete Continuous Steel Box Girder Bridge

With the development of society,Large span and wide range is about to the direction of highway bridge development.On the choice of cross section,mostly box section had been used in the bridge,in long-span box beam caused by live load effect which accounts for only about 20% of the total load,mostly caused by dead weight,unit weight in long-span Bridges reduces the important topic in front,the reasonable design of cross section is crucial.Its performance in the box beam cross section is wide box applications of thin walled section become more and more widely.Wide box thin-walled box girder due to the top of the box girder is wide,rib spacing is bigger,transverse effect is particularly obvious,therefore to wide box of thin-walled box beam transverse stress distribution study is very necessary.In this paper,a three spans continuous variable cross-section continuous rigid frame bridge as the research object,the deck width is 16 m,with single box section,belongs to the typical cases of thin-walled box beam wide,the author use the large general finite element software Midas FEA three-dimensional entity model is established for the bridge,the mid-span cross back first,after the first roof plate order,different section of the bridge in self-respect,transverse prestressing,vehicle load conditions of lateral force are analyzed in detail,and the need to pay attention to remind engineering personnel.Based on wide box of thin-walled box girder transverse stress analysis,found that under different conditions,certain parts box girder will there is a large tensile stress,this paper puts forward three ways to improve lateral force,namely,add diaphragm plate,change of section for the single box double room section,reasonable decorate transverse prestress;By not setting transverse diaphragm and diaphragm plate spacing is set to L,L / 2,L / 4 to establish solid finite element model,this paper coMPares and analyzes the diaphragm plate on its influence on the transverse force of gravity and partial load;By establishing the finite element model of single box double chamber section entities corresponding,and the gravity,the force of the vehicle under partial load conditions and single box section were analyzed to study the lateral force change conditions;By single weight,weight+prestressed,partial load and partial load+prestressing force analysis are studied under different working conditions prestressing effect on cross force of gravity and partial load.AS the results indicated,the reasonable putted forward decorate horizontal baffle spacing,single box double room instead of cross section for two kinds of methods of box girder cross force improve play a large role,and the transverse prestressing due to its own limitations,can be used as an auxiliary measure,hope this thesis can offer engineering construction in the field of study as a reference.