Title: Prestress loss calculations: Another perspective
Date Published: May-June 2016
Volume: 61
Issue: 3
Page Number: 68-85
Authors: David B. Garber, José M. Gallardo, Dean J. Deschenes, and Oguzhan Bayrak
https://doi.org/10.15554/pcij61.3-04

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Abstract

The estimation of prestress loss is required for design and analysis of prestressed concrete bridges and buildings. A proper balance must be struck between accuracy, precision, and conservatism for prestress loss estimation in order to safely and efficiently design prestressed concrete members. An extensive research project was undertaken in which 30 full-scale bridge girders with a variety of applicable design parameters were instrumented, constructed, monitored, and tested; a comprehensive experimental database containing data from 140 full-scale bridge girders was assembled; and an extensive analytical program was conducted to investigate the sensitivity of current estimation methods and implications of loss estimation on final designs. Through the work of this project, a prestress loss estimation procedure was developed that is simple to use, precise, and offers an appropriate level of conservatism. This procedure can be used for both time-dependent and final prestress loss estimation.

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