Pushing Construction And Anti Overturning Analysis Of Curved Steel Box Girder Bridge

With the continuous development of China’s transportation,as of 2018,China has built more than 800,000 bridges,reaching the world’s leading level of bridge construction.Curved steel box girder bridges have the characteristics of beautiful appearance,good visual effects,large span capacity,and fast installation speed,thus it occupies a large proportion in the built bridges.However,the stress characteristics and construction process of the curved steel box girder bridges are different from that of the straight one.Moreover,in recent years,the collapse of curved bridges has occurred frequently,which also brings a good early warning function to the design and construction of curved steel box girder bridges.Although the existing research has been relatively complete,it is rare to study the combination of the push-over construction of the curved beam bridge and the anti-overturn analysis after the bridge is completed.Therefore,in this paper,the development of curved bridge and the research on anti overturning of curved bridge in recent years are introduced,the relevant provisions of the domestic and foreign codes are studied.Furthermore,with the help of engineering examples,the safety analysis of the bridge in the jacking construction are analyzed.The influence of different parameters on the anti overturning performance of the bridge is investigated.The main work is as follows:(1)The jacking construction scheme of the engineering example is described and the key construction technology is analyzed.Combined with the actual bridge,the reasonable recommendations for the safety of the jacking structure of the steel box girder bridge are proposed.(2)A finite element model of jacking construction of curved girder bridge is established by using the FE software Midas Civil,and the construction stage analysis is carried out to study the bearing reaction of each pier in the process of jacking construction and the stress state of box girder in the process of jacking.Furthermore,according to the requirements of relevant codes at home and abroad,the longitudinal anti overturning calculation of the structure is carried out to verify the rationality of the design of the project.(3)The mechanism and calculation method of anti-overturning of box girder are discussed and analyzed,and the differences between different national codes and domestic new and old codes are compared.Based on the finite element model,the influence of pre-eccentricity of support,spacing between side supports,arrangement form of support and other parameters on the anti-overturning performance of the curved steel box girder bridge is analyzed,and reasonable suggestions for similar actual engineering design and construction are proposed.