What Is Fineness of Cement
The fineness of cement is a measure of cement particle size and is denoted in terms of the specific surface area of cement.
The Fineness Test of Cement is done by sieving cement samples through a standard IS sieve. The weight of a cement particle whose size is greater than 90 microns is determined.
Then the percentage of retained cement particles is calculated. This is known as the Fineness of cement.
Different Tests on Cement
The following tests are conducted on cement in the laboratory as follows:
- Fineness Test of Cement
- Consistency Test of Cement
- Setting Time Test of Cement
- Soundness Test of Cement
- The Heat of Hydration Test
- Specific Gravity Test of Cement
- Tensile Strength Test
- Chemical Composition Test
Why Fineness of Cement Test Required?
We know that cement hydrates when cement is mixed with water and a thin layer are formed around the particle.
This thin layer grows bigger and makes cement particles separate. Because of this, the cement hydration process slows down.
On other hand, cement smaller particles react much quicker than larger particles.
A cement particle with a diameter of 1µm will react entirely in 1 day, whereas the particle with a diameter of 10µm takes about 1 month.
But, there is a side effect of having too much smaller particles in cement results in a quick setting, leaving no time for mixing, handling, and placing.
Therefore to increase the setting time of cement, cement must be manufactured in a different range of particle sizes. The fineness of the cement test measures this parameter of cement.
Fineness Test of Cement
To determine the fineness of cement by using a 90 µm IS sieve as per IS: 4031 (Part 1) – 1996.
- 90µm IS Sieve,
- Weight Balance has a capacity of 10 mg to 100 g,
- Nylon or pure bristle brush
Fineness Test of Cement Procedure
- Collect a sample of cement and rub it with your hands. The Fineness test sample should be free of lumps.
- Take 100 gm of cement sample and note its weight as W1.
- Drop 100 gm of cement in a 90 µm sieve and close it with the lid.
- Now, shake the sieve with your hands by agitating the sieve in planetary and linear movements for 15 minutes.
- After that take the weight of the retained cement on the 90 µm sieve as W2. To calculate the fineness of cement formula is given below,
Fineness = (W2/W1) * 100
Then, calculate the percentage of Weight of cement retained on Sieve.
Repeat this procedure with three different samples of cement and average the values for accurate results.
The fineness of Cement Calculation
The following table shows the fineness of cement value,
|Sr.No.||Weight of Cement |
|Weight Cement Sample |
Retained on 90µm Sieve
|Fineness of Cement|
|1||100 gm||4.65||4.65 %|
|2||100 gm||8.25||8.25 %|
|3||100 gm||7.95||7.95 %|
Result: The standard value of fineness of cement should have fineness less than 10 % or fineness of cement should not be more than 10% as per IS Recommendations.
The size of the sieve used to test the fineness of cement is?
The size of the sieve used to test the fineness test of cement is 90 micron IS Sieve.
What is the value of the fineness of cement?
Generally, Cement used for construction should have a value of fineness less than 10%.
Why fineness of cement is important?
Cement smaller particles react much quicker than larger particles. A cement particle with a diameter of 1µm will react entirely in 1 day, whereas the particle with a diameter of 10µm takes about 1 month. If a fine cement particle is more in cement then it will be set too quickly and that not feasible on-site to place concrete properly.
fineness of cement
The fineness of cement is a measure of cement particle size and is denoted in terms of the specific surface area of cement. The weight of cement particle whose size is greater than 90 microns is determined and the percentage of retained cement particle are calculated. This is known as the Fineness of cement.
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