Silt specific weight: weight of 1 m³ by condition
Silt is a substance formed at the bottom of standing water bodies or in channels of flowing water. It is a mixture of very fine particles of organic and mineral origin. The average amount of silt fractions smaller than 0.01 mm reaches 50% of the total mass.
Under natural conditions this fine-grained material is in a viscous, flowing state. Lying at the bottom of water bodies such as seas or lakes, silt may consist of particles of disintegrating rocks and solid remains of living organisms inhabiting these water bodies. Depending on the main components saturating the silt, the following types are distinguished:
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calcareous, terrigenous, aleuritic and pelitic silts;
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diatom, radiolarian, pteropod and globigerina silts.
There are also silts saturated with remains of volcanic origin or putrefactive deposits formed as a result of decomposition of a large amount of organic matter. This substance, sapropel, causes active release of hydrogen sulfide.
How Much Does Silt Weigh?
The question of silt weight arises during construction work, transportation of bottom soil, calculation of the mass of silt deposits, determination of sapropel density and other technical tasks.
The average specific weight of silt sediment is taken as 1.6 t/m³. Depending on the type of silt and its physical condition, dry or wet, density changes accordingly. Silt in its natural state and the weight of loose sapropel have different density values. The data are shown in the table.
| Condition | Silt weight (t/m³) | Silt volume (m³/t) |
|---|---|---|
| Wet silt | 1.8-2.2 | 0.46-0.55 |
| Dry silt | 1.4-1.7 | 0.59-0.71 |
Use of Silt
Humans have learned to use silt for their needs. As the initial stage through which bound sedimentary rocks pass, silt can be used in the production of mineral extracts for animals and as a soil fertilizer in agriculture.
Lake sapropel is considered the best for improving soil quality. It contains many useful organic substances and minerals. It actively stimulates plant growth and development and is also a natural antiseptic.
Silt is sometimes considered an organic-mineral raw material for fertilizers, but it should not be applied to gardens without composition analysis and sanitary assessment. Bottom sediments may accumulate heavy metals, petroleum products, pathogens and excess salts. If the material is used in compost, proper maturation, origin control and agricultural standards are required; simply adding silt does not guarantee that infection risk disappears.
Some types of silt and bottom deposits are used as part of therapeutic muds in sanatorium practice. Usually, deposits from salt lakes that have passed composition and safety control are used for this. Silt should not be used independently for medical purposes: the properties of such materials depend on origin, composition and sanitary condition.
Frequently Asked Questions
How much does 1 m³ of silt weigh?
According to the table, wet silt weighs roughly 1.8-2.2 t/m³, while dry silt weighs about 1.4-1.7 t/m³. Actual mass depends on water content, organic matter, mineral particles and compaction.
Why does silt density vary so much?
Silt contains fine mineral and organic particles, water and pores. The more water it contains and the denser the deposit is, the heavier one cubic meter will be.
Can table values be used for a project?
They are suitable for a preliminary estimate, but slope, foundation, dredged material transport or sanitary calculations require laboratory data and the conditions of the specific site.