Effect of Keying-Induced Soil Remolding on the Ultimate Pull-Out Capacity and Embedment Loss of Strip Anchors in Clay
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 147, Issue 10
Abstract
In this paper, the keying of strip anchors in clay has been studied by employing a large deformation finite-element methodology coupled with a soil constitutive model that takes strain rate and soil remolding into considerations. The influences of soil strength degradation during keying on the loss of embedment and undrained pull-out resistance of anchors have been investigated by varying several factors, such as soil sensitivity, initial embedment depth, loading eccentricity, and shear strength heterogeneity. The methodology is validated with results from experimental and theoretical studies available in the literature. A generalized approach is developed to assess the maximum embedment loss and ultimate pull-out capacity. A combined dimensionless parameter as a function of the initial anchor depth and normalized equivalent soil strength is introduced for the prediction of maximum embedment loss. Ultimate pull-out factors normalized by an equivalent shear strength of soil are presented as a function of the initial embedment for different soil-strength heterogeneity and anchor eccentricity. Simplified expressions are provided for adoption in the routine design practice.
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Data Availability Statement
All data generated during this research and the Abaqus files are available from the corresponding author by request.
Acknowledgments
The authors would like to acknowledge the support provided by the Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Government of India (Grant No. YSS/2014/000628/ES) for carrying out the research work.
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Journal of Geotechnical and Geoenvironmental Engineering
Volume 147 • Issue 10 • October 2021
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© 2021 American Society of Civil Engineers.
History
Received: Nov 14, 2020
Accepted: Jun 1, 2021
Published online: Aug 12, 2021
Published in print: Oct 1, 2021
Discussion open until: Jan 12, 2022
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