Abstract:Research purposes : In recent years several large - span prestressed concrete continuous girder bridges appear large deflection in the main span after opened a period of time at home and abroad,which not only influences the comfort and security of the passing vehicle, but also threatens the safety of the bridge and shortens the service life of the bridge. This study aims to analyze how the prestress loss affect long — term deflection of large — span continuous girder bridge, the research conclusions may be the theory basis for taking effective measures to control the continuous down — warping in the design, construction and reinforcement for large — span prestressed concrete continuous girder bridge across.
Research conclusions : The deflection of large — span prestressed concrete continuous girder bridges is long — term growth,and its growth rate is uncertain. The mid — span deflection increases with the span length,the growth rate has a close relationship with the span length and prestress loss degree, and the prestress loss effect is more obvious when bridge span length is greater. The prestress loss of top deck has more effect on mid — span deflection than that of bottom slab. The creep and shrinkage of concrete and the prestress loss caused by these are the main reason of mid — span deflection large — span prestressed concrete continuous girder bridges. This research results can be applied to optimization design and construction for large — span prestressed concrete continuous girder bridges.
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BU Jian - qing,CUI Jin - can. Impacts of Prestress Loss on the Deflection for Large - span Prestressed Concrete Continuous Girder Bridges. Journal of Railway Engineering Society, 2014, 31(7): 57-61.
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