Atterberg limits

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Atterberg limits Series of thresholds which are observed when the water content of a soil is steadily changed. The ‘contraction limit’ occurs when sufficient water is added to a dry soil for contraction cracks to close. The addition of further water leads to plastic deformation at the ‘plastic limit’. The ‘liquid limit’ occurs when just enough water is then added for the soil to behave like a liquid. Knowledge of these limits is important for understanding and predicting hillslope failure. The difference in percentage water content between the liquid limit and the plastic limit is called the ‘plasticity index’.

Atterberg limits

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Atterberg limits A series of thresholds which are observed when the water content of a soil is steadily changed. The ‘contraction limit’ occurs when sufficient water is added to a dry soil for contraction cracks to close. The addition of further water leads to plastic deformation at the ‘plastic limit’. The ‘liquid limit’ occurs when just enough water is then added for the soil to behave like a liquid. Knowledge of these limits is important for understanding and predicting hill-slope failure.

Atterberg limits

views updated

Atterberg limits A series of thresholds that are observed when the water content of a soil is steadily changed. The ‘contraction limit’ occurs when sufficient water is added to a dry soil for contraction cracks to close. The addition of further water leads to plastic deformation at the ‘plastic limit’. The ‘liquid limit’ occurs when just enough water is then added for the soil to behave like a liquid. Knowledge of these limits is important for understanding and predicting hill-slope failure.