Dan D. Curtis
Acres International, 4342 Queen Street, P.O. Box 1001 Niagara Falls, ON, Canada L2E 6W1 ABSTRACT A review of the effects of alkali-aggregate reaction (AAR) in arch dams is presented. Numerous arch dams in the United States, Africa, Portugal and Spain have AAR and this paper presents a summary of observed/measured behavior of the dams. From the review, it is shown that arch dams can experience relatively large deformations and the displacement pattern is quite unique. A detailed finite element analysis of a typical arch dam is undertaken to demonstrate the mechanisms of behavior. From the analysis, it is shown that the stress-dependent behavior of AAR concrete expansion is a very important consideration for the proper analysis of arch dams. For example, an analysis which neglects the stress-dependent nature of concrete growth will significantly over-estimate the amount of tension in the dam. In addition, the unique displacement pattern of an arch dam with AAR is well matched by a finite element analysis which includes the stress dependent concrete growth behavior. Keywords: AAR, alkali-aggregate reaction, arch dam, finite element analysis, stressdependent.
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