08-08-2014, 11:06 AM
Test for Soundness (IS 4031) of Cement
Soundness is the ability of a hardened paste to retain its volume after setting.
A cement is said to be unsound (i.e. having lack of soundness) if it is subjected to delayed destructive expansion.
The Soundness test is an indication of excess of lime caused by inadequate burning of cement or excess of magnesia or sulphates .
Le chatelier’s Test
This test shows unsoundness dur to lime only. Unaerated cement paste at normal consistency is first tested for expansion. If the test results does not satisfy requirement of 10mm expansion .
Another test shall be made after aeration of cement by spreading of sample to a depth of 75mm at relative humidity of 50% to 80% for 7 days the expansion in this aerated cement test should not be more then 5 mm
Autocalve test
Autocalve Test is used for both lime and magnesia excess indication .
All the cement having a magnesia content more then 3 % is to be tested for soundness by this test with unaerated cement .
The test consist of heating bar made of cement paste with water of normal consistency and measuring its expansion
Soundness is the ability of a hardened paste to retain its volume after setting.
A cement is said to be unsound (i.e. having lack of soundness) if it is subjected to delayed destructive expansion.
The Soundness test is an indication of excess of lime caused by inadequate burning of cement or excess of magnesia or sulphates .
Le chatelier’s Test
This test shows unsoundness dur to lime only. Unaerated cement paste at normal consistency is first tested for expansion. If the test results does not satisfy requirement of 10mm expansion .
Another test shall be made after aeration of cement by spreading of sample to a depth of 75mm at relative humidity of 50% to 80% for 7 days the expansion in this aerated cement test should not be more then 5 mm
Autocalve test
Autocalve Test is used for both lime and magnesia excess indication .
All the cement having a magnesia content more then 3 % is to be tested for soundness by this test with unaerated cement .
The test consist of heating bar made of cement paste with water of normal consistency and measuring its expansion