Saturation is transient. It depends on density. The higher the density, the lower the moisture content at saturation. It is clearly related to the quantity of air voids. If air voids are present, saturation has not occurred.

Look at a moisture-density relationship curve (Proctor curve). The lines of "zero air voids" show the saturation point per unit weight. This is helpful in understanding the saturation points.

Do a few weight-volume calculations to also help you understand saturation.

you must know the specific gravity of the soil grains and you must also have some defined (molded or field) dry density. From there you can solve the weight and volume relations for any moisture content. You can also calculate the saturation moisture content from letting (calculating the condition for) all voids be filled with water.

f-d

¡papá gordo ain’t no madre flaca!

p.s., you may be able to do it by measuring soil suction.

f-d

¡papá gordo ain’t no madre flaca!

You can calculate it from the phase relationship

w(Gs)=e(Sr)...

If you know density/void ratio (e) and specific gravity (Gs), adopt Sr=1.0 and calculate w.