Deflection Control of Prestressed Box Girder Bridges
Publication: Journal of Bridge Engineering
Volume 19, Issue 5
Abstract
The models for prediction of creep in codes and design guides are mainly based on tests in which the load is sustained for a number of years, rarely exceeding 10; however, most models predict that creep reaches its extreme after approximately 30 years. An exception is the frequently accepted Model B3; it predicts indefinite increase of creep with the logarithm of the number of days of sustained loading. Analysis of deflection using Model B3 of a large number of bridges agrees with measured deflection in terms of magnitude and continued increasing tendency. Modern design requires satisfactory serviceability sustainable for a long life span. The absolute value of camber or deflection must not be excessive. This paper shows that by adopting Model B3, combined with appropriate prestressing, it is possible to satisfy this requirement for 125 years.
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Information
Published In
Journal of Bridge Engineering
Volume 19 • Issue 5 • May 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Feb 22, 2013
Accepted: Oct 1, 2013
Published online: Dec 26, 2013
Published in print: May 1, 2014
Discussion open until: May 26, 2014
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