Weight of soil in 1 m3, table of specific and volumetric soil weight
In engineering calculations, the specific weight of soil is usually treated as the weight of a unit volume of soil or its solid particles. The value depends on mineral composition, organic matter content, moisture and porosity. If the soil does not contain many plant residues, the specific weight of the solid particles usually changes only slightly. The table below gives values for several common soil types.
| Soil type | Specific weight, t/m³ | Specific weight deviation | |
| t/m³ | % | ||
| Fresh clay | 2.74 | ~0.027 | ~0.99 |
| Sand | 2.66 | ~0.010 | ~0.36 |
| Sandy loam | 2.70 | ~0.017 | ~0.63 |
| Loam | 2.71 | ~0.020 | ~0.74 |
| Black soil | 1.45 | ~0.05 | ~3.45 |
Volumetric soil weight
Volumetric soil weight is the weight of soil expressed per unit volume. It is not constant and changes depending on moisture content, compaction density and porosity. Dry and moist volumetric soil weight are usually distinguished.
The volumetric weight of dry soil, also called the weight of the soil skeleton, can be expressed by the formula: O = U x (1 - n), where U is the specific weight of the soil and n is porosity expressed as a fraction of one.
The volumetric weight of moist soil can be determined by the formula: O2 = O x (1 + W), where O is the volumetric weight of dry soil and W is the gravimetric moisture content.
Average volumetric weight values for moist soil are shown in the table below.
| Soil type | Porosity coefficient | Volumetric weight, t/m³ |
| Clay | 0.5 0.6 0.8 1.1 | 1.80 - 2.10 1.70 - 2.10 1.70 - 1.90 1.60 - 1.80 |
| Sand: - silty - fine, low-moisture - medium-grained - coarse and gravelly | not specified | 1.80 - 2.05 1.60 - 2.00 1.60 - 1.90 1.75 - 1.85 |
| Sandy loam | 0.5 0.7 | 1.70 - 2.00 1.50 - 1.90 |
| Loam | 0.5 0.7 1.0 | 1.80 - 2.05 1.75 - 1.95 1.70 - 1.80 |
| Peat | not specified | 0.55 - 1.02 |
Volumetric weight of soil under water
The volumetric weight of soil under water is the weight of a unit volume of soil at natural porosity in a water-saturated state. This value is used in calculations of slopes, foundation stability, suffosion assessment and other engineering tasks. It can be represented as the weight of the soil volume minus the weight of water displaced by solid particles: O3 = O - M, where O is the volumetric weight of soil and M is the amount of displaced water.
Frequently Asked Questions
Can the density of soil be used for precise calculations?
The density and weight values for soil in this article are reference values. They are suitable for preliminary estimates, but design, construction, production and other critical calculations should be checked against standards, material datasheets or measurement results.
Why can the actual weight of soil differ from the table?
The actual weight of soil depends on composition, moisture, temperature, porosity, fraction size, material grade and measurement conditions. Because of this, real values may differ from the average table data.
How do you calculate the mass of soil from density?
For an approximate calculation, use the formula: mass = density × volume. If the density of soil is given in kg/m³ and the volume is in m³, the result will be in kilograms.