Partial Safety Factors for Prestressed Concrete Girders Strengthened with CFRP Laminates
Publication: Journal of Composites for Construction
Volume 24, Issue 1
Abstract
This paper provides a framework for the calibration of partial safety factors in prestressed concrete (PC) girders strengthened in flexure with carbon fiber–reinforced polymer (CFRP) laminates. A hybrid approach was proposed to take advantage of comprehensive nonlinear numerical models in reliability analysis using a first-order reliability method (FORM) in conjunction with the response surface method (RSM). The PC girders selected for analyses were taken from real structures designed and built in the 1980s based on old standards that now require strengthening and upgrade due to partial corrosion of the prestressing strands. Using the proposed approach, a sensitivity analysis was performed to identify the most relevant variables and assess the area of CFRP laminates needed to restore capacity up to new design standards. A partial safety factor was proposed for strengthening PC girders using CFRP laminates. Sensitivity analysis showed that traffic loads and model uncertainties are the most important variables for calibration.
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Data Availability Statement
Some or all data, models, or code generated or used during the study are available from the corresponding author by request.
Acknowledgments
S. Gomes acknowledges the financial support of the Portuguese Science and Technology Foundation (FCT) through Ph.D. Grant No. SFRH/BD/76345/2011. D. Dias-da-Costa acknowledges the support from the Australian Research Council through Discovery Early Career Researcher Award (Grant No. DE150101703) and Linkage Grant No. LP140100591. This work was also supported by FCT, within Institute for Sustainability and Innovation in Structural Engineering (ISISE), Project No. UID/ECI/04029/2013.
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Published In
Journal of Composites for Construction
Volume 24 • Issue 1 • February 2020
Copyright
©2019 American Society of Civil Engineers.
History
Received: Sep 27, 2018
Accepted: Jun 19, 2019
Published online: Dec 4, 2019
Published in print: Feb 1, 2020
Discussion open until: May 4, 2020
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