Impact of Toe Resistance in Reinforced Masonry Block Walls: Design Dilemma
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 138, Issue 2
Abstract
Reinforced masonry block retaining walls are comprised of a narrow column of stacked blocks at their exposed end. This column is placed on a nonstructural leveling pad to facilitate the placement of facing units. Theoretically, this column can generate very large toe resistance to sliding. A recent publication indicates that an accepted design methodology implicitly counts on this resistance in assessing the reinforcement load. Although not calculated in this design, it unconditionally considers that over 60% of the resultant horizontal force in a 12-m-high wall is carried by the toe, which is made up of 0.3-m-deep blocks. This paper elucidates this issue by explicitly identifying the magnitude of toe resistance and critically reviews whether such high resistance is universally suitable for design. It shows that high toe resistance may not be feasible for most foundation soils. The high impact of toe resistance on the reinforcement force poses a design dilemma as to the reliability of this resistance, even if attainable. Practically, the leveling pad is not intended to serve as a critical structural element and thus should not be relied on for maintaining the toe resistance in long-term design. Economically, ignoring the toe resistance has little impact on the overall cost.
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Acknowledgments
The detailed and constructive comments by the reviewers are highly appreciated.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 138 • Issue 2 • February 2012
Pages: 236 - 240
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Jan 27, 2011
Accepted: Jun 10, 2011
Published online: Jan 17, 2012
Published in print: Feb 1, 2012
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