Abstract
A rigorous probabilistic-based approach for load and resistance factor design (LRFD) calibration of internal stability tensile rupture and pullout limit states for geogrid reinforced mechanically stabilized earth (MSE) walls is presented. Load and resistance factors are provided for different combinations of the load model with pullout model and the tensile strength model used in current practice. The load models are the AASHTO Simplified Method and the Simplified Stiffness Method. Resistance factors are tabulated for use in LRFD foundation practice in Canada which rewards designers with larger resistance factors for greater project level of understanding. Resistance factors are also provided that are amenable to US practice where the notion of level of understanding is not explicitly considered in LRFD practice. The paper demonstrates the application of the load and resistance factors for tensile rupture and pullout internal stability limit states using a design example and shows the reduction in required reinforcement strength using the Simplified Stiffness Method. The paper is of value to practitioners and LRFD code writers in the United States and Canada for future revisions of design specifications in their jurisdictions.
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Acknowledgments
The authors are grateful for financial support through an ENGAGE research grant awarded to the first author by the Natural Sciences and Engineering Research Council of Canada (NSERC) (Grant No. 94344-2013) and the Ministry of Transportation of Ontario (MTO) Highway Infrastructure Innovations Funding Program (Grant No. 9017-R-0030).
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 145 • Issue 11 • November 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Oct 5, 2018
Accepted: Apr 15, 2019
Published online: Aug 16, 2019
Published in print: Nov 1, 2019
Discussion open until: Jan 16, 2020
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