Determine Free Swell Index Of Soil

Posted in Civil Engineering Tests | Email This Post Email This Post |
Print Friendly

To determine the free swell index of soil as per IS: 2720 (Part XL) – 1977. 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. The apparatus used :

i) IS Sieve of size 425µm

ii) Oven

iii) Balance, with an accuracy of 0.01g

iv) Graduated glass cylinder- 2 nos., each of 100ml capacity

strong>Procedure to determine Free Swell Index Of Soil
i) Take two specimens of 10g each of pulverised soil passing through 425µm IS Sieve and oven-dry.

ii) Pour each soil specimen into a graduated glass cylinder of 100ml capacity.

iii) Pour distilled water in one and kerosene oil in the other cylinder upto 100ml mark.

iv) Remove entrapped air by gently shaking or stirring with a glass rod.

v) Allow the suspension to attain the state of equilibrium (for not less than 24hours).

vi) Final volume of soil in each of the cylinder should be read out.

REPORTING OF RESULTS
Free swell index = [Vd - Vk] / Vk x 100%
where,
Vd = volume of soil specimen read from the graduated cylinder containing distilled water.
Vk = volume of soil specimen read from the graduated cylinder containing kerosene.

Free Swell

Index

Degree of

expansiveness

LL

PL

SL

<20

Low

0.50

0-35%

>17%

20-35

Moderate

40-60%

25-50%

8-18%

35-50

High

50-75%

35-65%

6-12%

>50

Very high

>60%

>45%

<10%

We are thankful to Er Jithesh for submitting the table to us

More Entries :
Comments
  • sameer singh November 7, 2013 at 5:25 am

    what value should be suitable for using soil at different places such as for subgrade,for foundation…according to IS codes.ans what is significance of this test

  • Post a comment

1 2

Share Information

What is Civil Engineering

Journals Books And Softwares

Branches Of Civil Engineering

Civil Engineering Jobs

Follow Us On FB

Knowledge Center

Civil Engineering Universities/Events

Gallery - Civil Engineering Pictures

Civil Engineering Forum

civil engineering forum

Search


engineeringcivil.com awarded best online publication by CIDC 2013

Top Contributors

Yahoo Group - Civil Engineering Portal

Subscribe to EngineeringCivil.com


Powered by groups.yahoo.com

Recently Added

Civil Engineering Links

Follow Us On FB