Is cohesive soil load-bearing?

Cohesive soil has a low load-bearing capacity , as it softens when wet and loses stability. soil compaction or the application of gravel the load-bearing capacity can be improved.

How does non-cohesive soil behave in frost?

Non-cohesive soil such as sand or gravel remains largely stable in frost because it hardly stores any water. This makes it frost-proof and does not tend to swell or settle like cohesive soils .

Is cohesive soil frost-proof?

No, cohesive soil is not frost-proof. It stores a lot of water, which freezes in frost and damages the soil swell When thawing, it can lead to subsidence and cracks which affects stability.

Is rock a cohesive soil?

No, rock is not one of the cohesive soils . It consists of solid rock and is neither fine-grained nor water-binding. Cohesive soils such as clay or silt store water and change their consistency, while rock has a high Load capacity and stability.

Cohesive Soil – All Information

Zusammenfassung

Cohesive soil such as loam or clay changes its load-bearing capacity depending on the moisture content – and quickly becomes a problem for heavy machinery when wet.The result: subsidence, poor trafficability and unstable construction site conditions.

With targeted soil improvement, drainage, geogrids and off-road technology such as crawler platforms or all-terrain forklifts, you can still work safely and efficiently.Careful analysis of the subsoil is crucial – especially in changeable weather or on uneven surfaces.

Whether on construction sites, in agriculture, or during geotechnical investigations, soil quality plays a crucial role. Cohesive soils, in particular, can be challenging, as their properties change significantly depending on moisture content.

What is cohesive soil?

Cohesive soil consists of fine-grained material such as clay or silt. It is called cohesive soil because the fine particles retain water and thus hold it together. Unlike non-cohesive soils , which consist of coarse-grained material such as stone or sand and drain water quickly, cohesive soil can absorb large amounts of moisture. This causes it to become soft and mushy when wet, while during dry periods it shrinks, hardens, and cracks. This is particularly problematic for construction projects, as it causes the soil to lose stability.

Cohesive vs. non-cohesive soil – The most important differences

Characteristic	Cohesive soil (clay, silt)	Non-cohesive soil (sand, gravel)
Grain structure	Very fine-grained, high density	Coarse-grained, loose structure
Water absorption	Stores a lot of water, swells	Allows water to pass through quickly, remains stable
Load capacity	Low, risk of sinking	High, carries heavy loads well
Behavior in wet conditions	Muddy, slippery, difficult to drive on	Remains dimensionally stable, drains quickly
Behavior in dry conditions	Shrinks, forms cracks	Remains largely unchanged
Compactability	Can be compacted well, but difficult to loosen again	Difficult to compact, but stable after compaction

What does this mean for construction sites?

Cohesive soil is problematic for heavy machinery because it can deform and offers little stability.
Non-cohesive soil is more suitable for the use of work platforms and forklifts because it is more stable and has a better load-bearing capacity.

Problems with cohesive soil in construction

Especially on construction sites, cohesive soil can cause difficulties:

Sinking of machines such as aerial work platforms or forklifts.
Instability in buildings because the ground changes when it is wet.
Difficult to navigate , especially after rainfall.

Solutions for construction sites with cohesive soil

Soil improvement on the building site

To improve the load-bearing capacity of cohesive soils , a layer of gravel or crushed stone can be applied. This measure stabilizes the subsoil and prevents machinery from sinking in. Targeted soil compaction also helps to make the subsoil more load-bearing and increase its stability. Another option is the use of soil mats or geogrids , which distribute the load more evenly and so reduce the pressure on the soil. This type of stabilization is particularly important for loamy soils , which have a high proportion of fine-grained material such as clay and silt , as their properties can change relatively differently depending on the moisture content. In some cases, drainage can also be useful to regulate the water content in the soil and improve the load-bearing capacity in the long term.

Choosing the right machine

You should choose the right machinery when working on cohesive soils . This type of soil is often made up of a mixture of clay , silt and other fine-grained materials, which means that the load-bearing capacity of the subsoil is highly dependent on the moisture content. In contrast to non-cohesive soils , which are considered to be permeable to water and offer greater stability, cohesive soils can quickly lose their load-bearing capacity. The condition of the subsoil must be examined very carefully, especially under changing weather conditions, for example when rain or wind softens the soil even further. Depending on the composition and moisture content, the classification into suitable or unsuitable soil types for certain machines can change.

Crawler work platforms that distribute the weight better than wheels.
All-terrain forklifts and telehandlers specifically designed for soft ground.
Work platforms with support systems to provide additional stability.

The choice of the right machine therefore depends not only on the soil's load-bearing capacity, but also on its material composition and the friction between the individual grains . A careful analysis of the soil is essential before constructing a structure or using heavy machinery.

Pay attention to the weather

Adjust application times to avoid extreme humidity or dryness.
Ground test before starting work to ensure stability.

Conclusion

The difference between cohesive and non-cohesive soil is crucial for planning construction projects. Cohesive soil presents a greater challenge, as it changes significantly with moisture and causes machinery to sink. However, with the right measures—such as soil improvement and the selection of suitable machinery—work can be carried out safely even on cohesive soil.