It is necessary to check the quality of cement on site at the time of preliminary inspection. It is not possible to check all the engineering qualities of cement on site but there exist some field test which gives us a rough idea of quality of cement. While on site we can perform these field tests to judge the quality of cement. These field tests are as follows:
- Date of packing
- Colour
- Rubbing
- Hand Insertion
- Float Test
- Smell Test
- Presence of lumps
- Shape Test
- Strength Test
Field Tests on Cement
1. Date of Packing
Date of manufacture should be seen on the bag. It is important because the strength of cement reduces with age.
2. Colour
The cement should be uniform in colour. In general the colour of cement is grey with a light greenish shade. The colour of cement gives an indication of excess lime or clay and the degree of burning.
3. Rubbing
Take a pinch of cement between fingers and rub it. It should feel smooth while rubbing. If it is rough, that means adulteration with sand.
4. Hand Insertion
Thrust your hand into the cement bag and it should give cool feeling. It indicates that no hydration reaction is taking place in the bag.
5. Float test
Throw a small quantity of cement in a bucket of water. It should sink and should not float on the surface.
6. Smell Test
Take a pinch of cement and smell it. If the cement contains too much of pounded clay and silt as an adulterant, the paste will give an earthy smell.
7. Presence of Lumps
Open the bag and see that lumps should not be present in the bag. It will ensure that no setting has taken place.
8. Shape Test
Take 100g of cement and make a stiff paste. Prepare a cake with sharp edges and put on the glass plate. Immerse this plate in water. Observe that the shape shouldn’t get disturbed while settling. It should be able to set and attain strength. Cement is capable of setting under water also and that is why it is also called ‘Hydraulic Cement’.
9. Strength Test
A block of cement 25 mm*25 mm and 200 mm long is prepared and it is immersed for 7 days in water. It is then placed on supports 15000 mm apart and it is loaded with a weight of 340 N. the block should not show any sign of failure.
Sir in strength test why only 340N load is applied
Yes I also have this doubt
very useful article thank for admin of this blog
please explain float test?
Please read this also
http://readcivil.com/quality-water-used-concrete/
Please Read this
http://readcivil.com/types-cement-used-construction/
Good article…
Which class of cement is understood?
How do you understand the stale of cement? Is there a test method for this? Can you explain?
Thank you so much for important information about cement tests …
very important information
very nice information…..
DEAR SIR,
PLEASE TELL ME HOW TO IDENTIFY THIS CEMENT IS (33,43,53)GRADE CEMENT IN FIELD
very nice presentation on visual sound cement.
sir pleas provide details of test
Dear Sir,
I am confused in ” Floating test of cement”
You say ” Throw a small quantity of cement in a bucket of water. It should sink and should not float on the surface”
But theconstrutor.org says ” (e) If a small quantity of cement is thrown in a bucket of water, the particles should float for some time before it sink.”
Let me know clearly ” sholud float or should not float”.or can you guide me anything for reference. Thanks for your kindreply.
Thank you
cement particles should float sometime before it sinks…..
if it sinks directly it indicates cement particles are larger in size & clickers are not crushed properly
good presentation!. Thank you!!
Thank you.
Thank you so much for important information about cement tests …
PLEASE REQUIRED TEST REPORT WITH ALL DETAIL
good decription
very good presentation. it will help QA QC engineers for better performance. many thanks.