Long-Term Deflections of Cantilever Segmental Bridges

Jaroslav Navrátil, Miloš Zich


The long-term deflections of cast-in-place segmental bridges constructed using the cantilever method are often larger than the deflections expected in the design. A detailed structural analysis and monitoring of these types of bridges have therefore become a matter of interest. The paper gives a comprehensive analysis of phenomena that frequently conspire to cause long-span pre-stressed concrete bridges to deflect more than predicted. The analysis is based on a parametric study and long-term monitoring of the behaviour of a motorway bridge across the Vltava River in the Czech Republic. To reveal and quantify possible reasons for excessive bridge deflections, a detailed time-dependent analysis was carried out. The results of the study were compared with in-situ measurements that have been regularly carried out since the very early stage of construction. Theoretical values of the increments of deflections, pre-stressing forces and concrete strains were compared with the measurements.


prestressed bridges; concrete bridges; long-term deflections; long-term behaviour; time-dependent analysis; creep; shrinkage

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DOI: 10.3846/bjrbe.2013.24


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