Research On Excessive Deflection Of Midspan In Long-span Continuous Rigid Frame Bridges

In recent years, prestressed concrete continuous rigid frame bridge with itscharacteristics of great spanning capacity, economical and practical, has been widely used inbridge construction. But along with the construction of the bridge, excessivemid-span deflection problem increasingly prominent, seriously affected the safety, durabilityand the normal use of the bridge structure. Therefore, study how to control the problem ofmid-span deflection of the large span prestressed concrete continuous rigid frame bridge haspractical significance.This paper analyzes the development and research status of long-span continuous rigidframe bridge, Introduced the instance of the deflection diseases of bridge. From the twoaspects of creep of concrete and prestressed reinforcement, mechanism of action on thestructure and the effect on the deflection of continuous rigid frame bridge are analyzedtheoretically. Taking a large continuous rigid frame bridge in shanxi province as anengineering background, built finite element model, calculate and analyse finite elementmodel, study the effect of concrete creep, prestress loss and other factors on the mid-spandeflection of long-span continuous rigid frame bridge. The control measures for thephenomenon of excessive deflection of long-span continuous rigid frame bridge are presentedfrom the aspects of design, construction and operation management etc.