geotech.lab.index.get_plasticity_index#

DataFrame.geotech.lab.index.get_plasticity_index()#

Calculate and return the plasticity index.

The plasticity index is calculated as the difference between the liquid limit and the plastic limit.

Requires:

liquid_limit
plastic_limit
Returns:
Series

Series with plasticity index values.

Notes

The plasticity index is defined as:

\[PI = LL - PL\]

where:

  • \(PI =\) plasticity index, %,

  • \(LL =\) liquid limit, %,

  • \(PL =\) plastic limit, %.

References

[1]

ASTM International. (2018). Standard test methods for liquid limit, plastic limit, and plasticity index of soils (ASTM D4318-17e1). https://doi.org/10.1520/D4318-17E01

Examples

>>> df = pd.DataFrame(
...     {
...         "point_id": ["BH-1"],
...         "bottom": [1.0],
...         "liquid_limit": [47.5],
...         "plastic_limit": [25.3],
...     }
... )
>>> df.geotech.lab.index.get_plasticity_index()
0    22.2
Name: plasticity_index, dtype: Float64