Improving Existing Inverted-T Bent Caps for Serviceability and Strength by Retrofitting with Supplemental Steel
Publication: Journal of Structural Engineering
Volume 148, Issue 7
Abstract
Undesirable cracking is commonly observed in existing bridge bents with inverted-T bent caps at the web-to-ledge interface. Although the cracking is unexpected, such cracks may decrease service life and are possible signs of structural deficiencies. In this study, concepts of retrofit solutions for improving the performance of such bent caps were developed and experimentally investigated. The solutions were designed to provide supplemental ledge and hanger load paths by attaching additional steel components: a post-tensioning (PT) threadbar with a “catcher” channel or end-region stiffeners. Experimental test results demonstrated the retrofitted inverted-T bent caps remained in a good (operational) condition to levels above the service limit state and had load carrying capacity up to 60% above the specified ultimate load demands. These experimental observations for both as-built and strengthened bent caps were compared to the calculated strength capacities, and the code-based strength capacities were shown to be overconservative. Repair and retrofit design recommendations are provided, including limitations, based on the experimental investigation.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
This project was conducted in cooperation with the Texas Department of Transportation (TxDOT) under Project 0-6893. The authors would like to express appreciation to TxDOT for their financial support and collaborative efforts. The project was conducted at Texas A&M University (TAMU) through the Texas A&M Transportation Institute (TTI). The findings and opinions presented herein are those of the authors and are not necessarily those of the sponsoring agency.
References
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Information
Published In
Journal of Structural Engineering
Volume 148 • Issue 7 • July 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Jul 20, 2021
Accepted: Feb 23, 2022
Published online: May 6, 2022
Published in print: Jul 1, 2022
Discussion open until: Oct 6, 2022
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