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Theodore Ray
Planning and development surveyor
Asked a question last year

What is adsorbed water, and how does it affect the permeability of soil?

What is adsorbed water, and how does it affect the permeability of soil?

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For fine-grained soils there will be a microscopic water layer bound around the grains due to some electrochemical process. This water is called adsorbed water or hygroscopic water. Adsorbed water fills the voids of the soil. For clayey soil, the adsorbed water is in the diffused double-layer form.

The presence of adsorbed water around soil grains consumes a considerable amount of void space. It will intact reduce the permeability of soil though already voids contain some amount of water. Due to the reduction in effective pore space, water is not free to move through soil and thus reduces the permeability.

Meaning of absorbed water:

Here I will give you the answer to your first question, please have a look;

Simply we can say if the water that fills the voids of soil is nothing but absorbed water.

When water that is held in a film on the surface of the soil particle than that type of water is nothing but adsorbed water.

Whenever soil is transported with the help of wind then that type of soil is nothing but aeolian soil

The amount of water absorbed in the composites was specially calculated with the help of weight difference between the samples exposed to distilled water and the wetting and drying cycled samples.

The cycles of wetting and drying also have an influence on the water absorption curves

Thank you 

Hi, soil is a tri-axial material which contains air water and solids. The air are the remains present in the pores of soil. Permeability is the property of the soil to transmits the water through the series of pores through it. The water absorbed by the soil are remains present in pores.it12 blocks the powers and restrict the further absorption of water or even passing of water from the soil pores. This type of soil is called a saturated soil. It has 100% saturation. That is for the addition of water is not allowed. It makes water money in nature and increases its viscosity and flowability. The stability of soil decreases, which is the main cause of land slides during rainy season.

Flenn Hale
Construction Manager

Adsorbed water

The term ‘Adsorbed water’ as it applies to the area of reclamation can be defined as ‘ Water in a soil or rock mass, held by physico-chemical forces, having physical properties substantially different from absorbed water or chemically combined water, at the same temperature and pressure’.

How affects the permeability :

Fine particles of clay are surrounded by films of adsorbed water. Forces of adsorption and development of diffuse ion-layer around the clay particles create immobilized hydrodynamic layers of water, thereby reducing the effective pore space available for seepage.