Static Behavior of Cob: Experimental Testing and Finite-Element Modeling
Publication: Journal of Materials in Civil Engineering
Volume 31, Issue 4
Abstract
The aim of this paper is to implement a numerical model to reproduce the nonlinear behavior of cob walls under shear loading. Axial compression, pull-off, and diagonal compression tests were carried out to derive the mechanical parameters. In addition, the stress-strain relationships, the nonlinear behavior, and the failure modes were defined. The experimental results were then used to calibrate a finite-element model. The material behavior was simulated through a macromodeling approach adopting the total strain rotating crack model. A sensitivity analysis was conducted to assess the effects of varying the parameters with higher uncertainty on the structural behavior. The numerical model achieved good correspondence with the experimental results in terms of simulation of the shear stress–shear strain relationship and of damage pattern.
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Acknowledgments
The authors wish to express their gratitude to Mr. André Gardei for his important support in the experimental program and to Mr. Andreas Barner and Ms. Manuela Peuschel for their support with photogrammetric analyses. This study was funded by the European Commission within the framework of the project NIKER (Grant No. 244123) dealing with improving immovable Cultural Heritage assets against the risk of earthquakes. The study was partly financed by FEDER funds through the Competitivity Factors Operational Programme (project POCI-01-0145-FEDER-007633) and by national funds through the Portuguese Foundation for Science and Technology (project PTDC/ECM-EST/2777/2014 and Grant No. SFRH/BPD/97082/2013).
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Published In
Journal of Materials in Civil Engineering
Volume 31 • Issue 4 • April 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Apr 5, 2018
Accepted: Sep 12, 2018
Published online: Jan 30, 2019
Published in print: Apr 1, 2019
Discussion open until: Jun 30, 2019
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