What is free swell of soil?

Objective: Free swell or differential free swell, also termed as “free swell index”, is the increase in volume of soil without any external constraint when subjected to submergence in water.

What is the swell index?

The swell index which is the slope of the rebound curve of void ratio versus the logarithm of the effective pressure curve is used to estimate the consolidation settlement of over-consolidated fine grained soils.

How do you classify expansive soil?

Based upon the Atterberg limits, the degree of expansion of a soil can be classified as presented in Table 11.3. Similarly, as per the ASTM D4829-11, the degree of expansion may be very low (EI = 0–20), low (EI = 21–50), medium (EI = 51–90), high (EI = 91–130), and very high (EI > 130), where EI is the expansion index.

What do you mean by Free Swell Index?

DEFINITION • Free Swell Index is the increase in volume of a soil, without any external constraints, on submergence in water.

What is the importance of swelling index?

The swell index test procedure is used to determine the general swelling characteristics of bentonite clay. The Swell Index test has not been demonstrated to have a proportional correlation to hydraulic properties, a high swell is considered by most to be a good indicator of bentonite quality.

How do you calculate swell index?

Is code a soil classification?

According to this system, the symbols of the various soils are as: Gravel (G), Sand (S), Silt or Silty (M), Clay or Clayey (C), Organic (O), Peat (Pt), Well graded (W), Poorly graded (P). To classify the fine-grained soil, plasticity chart (as shown in Figure 2) is used.

How do you calculate swelling pressure in soil?

The difference between the final and initial dial readings of the proving ring gives total load in terms of division which when multiplied by the calibration factor gives the total load. This when divided by the cross-sectional area of the soil specimen gives the swell pressure expressed in kN/m2 (kgf/cm2).

What is the unit of compression index?

The Compression Index (Cc) is equal to the slope of the graph of pressure versus void ratio (log scale) [7]. Compression Index (Cc) for clay is in the range 0.258 to 0.968, while for laterite soil was in the range 0.101 to 0.940. Value of Compression Index (Cc) is different between each type of soil.

What is swelling index of bentonite?

Overview: Bentofix® Sodium Bentonite clay is widely known for its high swelling characteristics. A typical sodium bentonite clay has the ability to absorb 4-5 times its own weight in water and can swell 5 – 15 times its dry volume at full-unconfined saturation.

What is swelling of coal?

Coal swelling is observed when one or both of the gases (carbon dioxide or methane) are sorbed into the coal matrix. Similarly, coal shrinkage is observed when one or both of the gases (carbon dioxide or methane) are desorbed.

Why is the foaming index determined?

Foam Index test is a rapid method to determine the relative levels of Air Entraining Agent (AEA) needed during concrete mixing, with or without mineral additives like combustion fly ash, that control air void volumes within cured concrete.

What do you mean by swelling power?

BACKGROUND- Bentonite. is a natural, colloidal, hydrated aluminium silicate that has been processed to remove grit and non-swelling components of the ore. It is under the category of pharmaceutical aid.

What is swelling caused by?

Swelling is the result of the increased movement of fluid and white blood cells into the injured area. The release of chemicals and the compression of nerves in the area of injury cause pain. The pain and swelling can keep the athlete from using the injured part, serving to protect it from further injury.

What is caking index of coal?

caking index. measure of the magnitude of the binding strength between coal particles or between coal particles and inert particles after coal is heated at 850 °C.