ity range is similar to formation booms. Forma-
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range, are limited to shallower rivers due to
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cost. Tension weirs built to date (including the
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Cold Regions Research and Engineering Labor-
Of the two groups of breakup structures,
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Atkinson, C.H. and T.W. Waters (1978) Ice re-
In addition, the weir breakup structures do not
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depend solely on arching and the formation of a
of design expectations with actual performance.
grounded jam to impound flow and reduce the
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