Evolution of Localization Length during Postpeak Response of Steel in Tension: Experimental Study
Publication: Journal of Engineering Mechanics
Volume 146, Issue 7
Abstract
This paper presents an experimental study into the influence of localization length () and its evolution during the postpeak response of cylindrical low-carbon steel bars. A novel longitudinal strain method for the determination of the localization length is compared to the average strain method. Four specimen lengths [38.1 mm (1.5 in.), 76.2 mm (3 in.), 152.4 mm (6 in.), and 304.8 mm (12 in.)] with a diameter of 12.7 mm (0.5 in.) were tested according to ASTM A370 standards. A three-dimensional digital image correlation (3D DIC) measurement system was used to record the longitudinal and transverse deformations along the specimen length. The results indicate that the engineering stress-strain relation up to the peak load is almost identical for all tested specimens. However, the postpeak response shows a steeper softening response for longer specimens. Two methods were used to extract the localization length from the longitudinal engineering strain profile. The average strain method shows a length dependence for different specimen lengths, while the longitudinal strain method eliminates the length dependence. The consistency of the localization length obtained through the longitudinal strain method enables improved generalized analytical relationships. Linear and exponential curve fitting formulae are given to predict the localization length for a generic specimen.
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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. Items available include the data from the experimental tests (load, displacement, longitudinal strain, and transverse strain).
Acknowledgments
Student support for Saif Altai was provided by the Ministry of Higher Education and Scientific Research (MoHESR), Iraq. The opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the sponsor.
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Published In
Journal of Engineering Mechanics
Volume 146 • Issue 7 • July 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Mar 1, 2019
Accepted: Feb 18, 2020
Published online: Apr 28, 2020
Published in print: Jul 1, 2020
Discussion open until: Sep 28, 2020
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