Extract from CETMEF, 2005. Note on weirs : synthesis of flow laws at the right of weirs and spillways. Centre d'Études Techniques Maritimes Et Fluviales, Compiègne.
@@ -32,10 +32,12 @@ Extract from CETMEF, 2005. Note on weirs : synthesis of flow laws at the right o
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> On the other hand, the closer the upstream water line is to the weir crest, the greater the width of the weir appears in relation to the breadth of the water flowing over it and therefore the broader the weir crest appears.
> A weir in a river thus belongs to one of the three following categories:
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> - sharp-crested weir
> - broad-crested weir
> - weir with undefined crest
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> In order to determine the type of weir studied, the following conditions must be verified:
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> - if $C < \frac{H_1}{2}$, then the threshold is sharp-crested;
> - if $C > \frac{2H_1}{3}$, then the threshold is broad-crested.