Long-Term Deflections of Cantilever Segmental Bridges

Authors

  • Jaroslav Navrátil IDEA RS Ltd, South Moravian Innovation Centre, U Vodárny 2a, 616 00 Brno, Czech Republic
  • Miloš Zich Dept of Concrete and Masonry Structures, Brno University of Technology, Veveri 95, 602 00 Brno, Czech Republic

DOI:

https://doi.org/10.3846/bjrbe.2013.24

Keywords:

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

Abstract

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.

References

Bažant, Z. P.; Hubler, M. J. 2013. Theory of Cyclic Creep of Concrete Based on Paris Law for Fatigue Growth of Subcritical Microcracks. Structural Engineering Report No. 13-07/936c. Dept of Civil and Environmental Engineering, Northwestern University, Illinois, USA.

Bažant, Z. P.; Li, G. H.; Yu, Q.; Klein, G.; Křístek, V. 2008. Explanation of Excessive Long-Time Deflections of Collapsed Record-Span Box Girder Bridge in Palau, Preliminary Report, in The 8th International Conference on Creep and Shrinkage of Concrete. September 30, 2008, Ise-Shima, Japan.

Bažant, Z. P.; Baweja, S. 2000. Creep and Shrinkage Prediction Model for Analysis and Design of Concrete Structures: Model B3, in Adam Neville Symposium: Creep and Shrinkage‒Structural Design Effects, ACI SP–194. Am. Concrete Institute, Farmington Hills, Michigan, 1–83.

Favre, R.; Markey, I. 1994. Generalization of the Load Balancing Method, in The 12th FIP Congress, Béton Précontraint en Suisse. Washington, 32–37.

Florian, A.; Navrátil, J. 1998. Stochastical Analysis of Highway Bridge Across Vltava River, in Structural Safety and Reliability, ed. by Shiraishi, Shinozuka, Wen, in Proc. of the 7th International Conference Icossar ´97: 1957–1960. Rotterdam: Balkema.

Křístek, V.; Bažant, Z. P.; Zich, M.; Kohoutková, A. 2006. Box Girder Bridge Deflections, ACI Concrete International Journal (28): 55–63.

Navrátil, J. 1999. Study of Long-Term Behaviour of Cast-in-Place Segmental Bridge, in Proc. of the Symposium 1999. Prague: Viacon Agency, 469–474.

Navrátil, J.; Zich, M.; Křístek, V. 1999. Influence of Differential Shrinkage on Deflection of Box Girders (in Czech), in Proc. of the Conference Concrete Days 1999. Pardubice: ČBS ČSSI, 174–181.

Navrátil, J. 1998a. Updating of Concrete Creep and Shrinkage Prediction (in Czech), Stavební obzor 2: 44–50.

Navrátil, J. 1998b. The Use of the B3 Model Extension for the Analysis of Bridge Structures (in Czech), Stavební obzor 4: 110–116.

Navrátil, J. 1992. Time-Dependent Analysis of Frame Structures (in Czech), Building Research Journal 7(40): 429–451.

Petřík, V.; Křístek, V. 1998. The Deflection Analysis of Box Girder Bridges with Respect to Shear Lag (in Czech). Project No. S303/120/602. Dept of Transport and Communications of Czech Republic, Prague: Czech Technical University.

Downloads

Published

27.09.2013

How to Cite

Navrátil, J., & Zich, M. (2013). Long-Term Deflections of Cantilever Segmental Bridges. The Baltic Journal of Road and Bridge Engineering, 8(3), 190-195. https://doi.org/10.3846/bjrbe.2013.24