Optical Fiber Strain Measurements and Numerical Modeling of Load Tests on Grouted Anchors
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 145, Issue 12
Abstract
This paper reports on the behavior of a grouted anchor instrumented with a fiber optic strain sensor in the grout body along the entire anchor length. During load tests up to the estimated pull-out capacity, the strain measurements indicate that a delamination occurs in the tendon bond length between the steel tendons and the grout body. The upper delaminated part of the grout body is under compression, whereas the lower bonded part of the grout body is under tension. This delamination gradually progresses as the anchor load increases. Furthermore, a significant part of the load is transferred from the anchor to the soil in the tendon free length. The anchor behavior is further modeled with a one-dimensional finite-element model that includes the steel tendons and the grout body, where an interface damage model is used to account for possible delamination of the interface. The numerical model confirms that the observed compressive and tensile strains in the grout can be related to a delamination of the steel strands in the tendon bond length. The experiment and numerical modeling demonstrate how optical fiber measurements in the grout body can be used, in operational conditions, to assess the anchor behavior, the mobilization of the soil resistance, and the estimation of the remaining anchor capacity.
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Data Availability Statement
The measurement data and model output are available from the corresponding author by request.
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Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 145 • Issue 12 • December 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Dec 3, 2018
Accepted: Jun 28, 2019
Published online: Sep 18, 2019
Published in print: Dec 1, 2019
Discussion open until: Feb 18, 2020
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