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Honbest is the depth of the channel below the revetment.
Mbestorting is the horizontal projection of the length of the revetment.
In case no slope protection is present, if over the entire channel depth softening sensitive sand is present, this margin is thus equal twice the fictive channel depth (M = 2 H).
The inclined part of the observation profile in line with the horizontal portion. The inclination of the slope depends on the channel depth:
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