Estimating Plastic Strain and Residual Strain Capacity of Earthquake-Damaged Steel Reinforcing Bars
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VIEW THE REPLYPublication: Journal of Structural Engineering
Volume 144, Issue 5
Abstract
Modern seismic codes are based on capacity design and the hierarchy of strength philosophy that allows inelastic response in case of severe earthquakes. Thus, in most traditional systems, earthquake damage develops at well-defined locations in reinforced concrete (RC) structures. Plastic hinges form in beams, in coupling beams, and at the base of columns and walls. There is a perceived strong demand from government and industry to develop techniques for assessing damage to steel reinforcement bars embedded in cracked structural concrete elements of earthquake-damaged buildings. Although some studies have been conducted recently, a validated methodology to quantify the level and extent of plastic deformation and residual strain capacity has yet to be widely accepted. In this paper, a damage assessment methodology is proposed based on empirical relationships between hardness versus strain and residual strain capacity that accounts for the effects of strain aging. The method has been applied to buildings damaged in the 2010/2011 sequence of earthquakes in Christchurch, New Zealand.
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Acknowledgments
The authors would like to express their gratitude to the Natural Hazards Research Platform and the MBIE Building System Performance Branch for financial support through the SAFER Structures Research Project, Pacific Steel, and Bruce Roberts for providing the steel used in this research. We also acknowledge the many helpful discussions with Professor Norman Dowling from Virginia Tech and the late Emeritus Professor Les Erasmus from University of Canterbury.
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Published In
Journal of Structural Engineering
Volume 144 • Issue 5 • May 2018
Copyright
©2018 American Society of Civil Engineers.
History
Received: May 25, 2016
Accepted: Sep 6, 2017
Published online: Feb 19, 2018
Published in print: May 1, 2018
Discussion open until: Jul 19, 2018
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