Index tests

pyeng.geotechnical.classification.index_tests.plasticity_chart(liquid_limit, plasticity_index, fail_silently=True, **kwargs)

Classification of fine-grained soils according to their plasticity. The plasticity chart comprises six regions divided by the so-called A-line. Soil above the A-line are inorganic clays and soils below the A-line are inorganic silts, organic silts or organic clays.

Parameters:
  • liquid_limit – Liquid limit (\(w_L\)) [\(\%\)] - Suggested range: 0.0<=liquid_limit<=100.0
  • plasticity_index – Plasticity index (\(PI\)) [\(\%\)] - Suggested range: 0.0<=plasticity_index<=70.0
\[PI = 0.73 (w_L - 20)\]
Returns:Classification [\(-\)], Aline plasticity index (\(PI_{Aline}\)) [\(\%\)]
Return type:Python dictionary with keys [‘classification [-]’,’aline_PI [%]’]
../../../_images/Casagrande_chart.PNG

Plasticity chart according to Casagrande (1948)

Reference - Casagrande, A. (1948). Classification and Identification of Soils. Transaction, ASCE, vol. 113, 901-930.