Title: Temperature Induced Deformations in Match Cast Segments
Date: July-August, 1995
Volume: 40
Issue: 4
Page number: 62-71
Author(s): Carin L. Roberts Wollmann, John E. Breen, Michael E. Kreger
https://doi.org/10.15554/pcij.07011995.62.71

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Abstract

During the match casting operations of precast segments for segmental post-tensioned concrete box girder bridges, a problem can arise due to the heat of hydration of the newly cast segment. When the  segments have a particularly high ratio of wing span to segment length, warping of the match cast segment can occur due to a thermal gradient that is caused by the high temperatures in the adjacent  newly cast concrete. This warping, or bowing, has subsequently caused problems during erection operations. This paper presents the results of a field study of this phenomenon. Concrete temperatures  and segment deformations measured during the casting of several segments for the San Antonio "Y" project are reported along with observations from the erection operations. A simple method is presented to  determine whether, for a given bridge, measures to reduce the thermal gradient during match casting should be taken. 

References

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2. Podolny, W. Jr., "The Cause of Cracking in Post-Tensioned Concrete Box Girder Bridges and Retrofit Procedures," PCI JOURNAL, V. 30, No. 2, March-April 1985, pp. 82-139.

3. Figg and Muller Engineers, Prestressed Concrete Segmental Bridge Construction Manual, Bridge Contractors Seminar, Asheville, NC, June 1981.

4. Roberts, C. L., "Measurement Based Revisions for Segmental Bridge Design and Construction Criteria," Doctoral Dissertation, University of Texas at Austin, Austin, TX, December 1993.