Moisture Content

From TML Testing Wiki
(Redirected from Water content)
Jump to: navigation, search
An idealized soil.

Moisture Content, also known as the Water Content, is the quantity of water or moisture contained within a material. The moisture content is commonly referred to as the percentage of the mass of water in relation to the mass of wet material or gross water content by weight (w1) except in geotechnical engineering, soil mechanics and woodworking where the moisture content is commonly referred to as the percentage of the mass of water in relation to the mass of dry material or net water content by weight (w).

The gross water content by weight and net water content by weight are both a measurement of the gravimetric water content of a material. Both the gross water content and net water content can also be determined by volume. This is known as the volumetric water content of a material.

The Transportable Moisture Limit (TML) of a Group A liquefiable cargo, as determined in Appendix 2 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code) is reported in the gross water content by weight.

Gravimetric Water Content[edit]

Relationship between Gross Water Content by Weight and Net Water Content by Weight.

Gross Water Content by Weight (GWC)[edit]

The following equation is used to determine the gross water content by weight:

Eqn (5).png

Where:

w1 = gross water content by weight (%),
Ww = mass of water,
Ws = mass of solids and
Wt = total mass.

Net Water Content by Weight (NWC)[edit]

The following equation is used to determine the net water content by weight:

NWCequation2016.png

Where:

w = net water content by weight (%),
Ww = mass of water and
Ws = mass of solids.

Convert Between Gravimetric Water Contents[edit]

To convert the net water content by weight to the gross water content by weight the following equation can be used:

Gwctonwcwithw.png

Where:

w1 = gross water content by weight (%) and
w = net water content by weight (%).

You can also use the converter provided on the main site by clicking the following link:

http://tmltesting.com/calc-moisturecontent.php


Volumetric Water Content[edit]

Relationship between the Gross Volumetric Water Content and Net Water Content by Weight for soils with different densities.
Relationship between the Gross Volumetric Water Content and Gross Water Content by Weight for soils with different densities.

The following equations are used to determine the gross volumetric water content:

VolumetricWaterContent5.png
VolumetricWaterContent6.png

Where:

θ = gross volumetric water content (%),
Ww = mass of water,
Ws = mass of solids,
ρw = density of water (~1 t/m3 or g/cm3),
ρd = dry density (t/m3 or g/cm3),
ρb = bulk density (t/m3 or g/cm3),
Vw = volume of water,
Vt = total volume,
w = net water content by weight (%) and
w1 = gross water content by weight (%).

You can also use the converter provided on the main site by clicking the following link:

http://tmltesting.com/calc-moisturecontent_vol.php


To determine the net volumetric water content, which is rarely used, the volume of solids (Vs) is used instead of the total volume (Vt) or:

VolumetricWaterContent7.png

Where:

θnet = net volumetric water content (%),
w = net water content by weight (%) and
ρst = specific gravity or particle density (t/m3 or g/cm3).

See Also[edit]


Share your opinion