Stability During Sudden Drawdown

"Sudden drawdown stability computations are performed for conditions occurring when the water level adjacent to the slope is lowered rapidly. For analysis purposes, it is assumed that drawdown is very fast, and no drainage occurs in materials with low permeability; thus the term “sudden” drawdown. Materials with values of permeability greater than 10-4 cm/sec can be assumed to drain during drawdown, and drained strengths are used for these materials."

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