specific gravity of cement | specific gravity of opc cement | ppc cement specific gravity
Specific gravity of cement | specific gravity of opc cement | ppc cement specific gravity
Specific Gravity of Cement
We all know that the specific gravity of cement is 3.15, But we don't know why specific gravity of cement is required and practically where it is used. for your every question we will find here answer
In this post, we will learn
- What is Specific Gravity?
- Why are we calculating this value for cement?
- Significance of specific gravity of cement
- Experiment to determine this value
Definition – Specific Gravity is just a comparison between the weight of a volume of a particular material to the weight of the same volume of water at a predetermined temperature.
It is a value to calculate whether the material is able to sink or float on water. Every material has some specific gravity. The value is normally in digits like 0.1 – 100. If the value is less than 1, then the material will float on water. If the value is greater than 1, then the material will sink.
3.15g/cc means the cement is 3.15 times heavier than the water of the same volume.
Why are we calculating this value for cement?
If the cement has been exposed to extreme moisture content then, the specific gravity of cement will differ because of the moisture content present in the pores which alter the specific gravity.
Normally our nominal mix design is based on the value of specific gravity of cement as 3.15. The value will change over time if the cement is exposed to various weather conditions. So it is essential to determine the specific gravity of cement before using it.
This is the reason why we need to calculate the specific gravity of cement
The significance of specific gravity of cement
We all know that the water-cement ratio is an important factor. It is directly proportional to workability (free to flow) and the strength of bonding. If the cement has already more moisture in it then, the value of the water-cement ratio will actually affect the workability and strength rather than increasing it.
If the specific gravity of cement is greater than 3.19 then, the cement is either not minced finely as per the industry standard or it has more moisture content which will affect the mix and bonding.
How to calculate cement specific gravity?
Le chatlier apparatus used to find specific gravity of cement
Required Materials & Apparatus:
- Ordinary Portland Cement
- Kerosene
- Le-Chatelier Flask capacity of 250 ml or Specific Gravity Bottle / Pycnometer (100 ml)
- Weighing balance with 0.1 gm accurate
Why are we using Kerosene instead of water?
To calculate specific gravity for any material, we have to use water. But water reacts with cement & forms calcium oxide. So that we are using Kerosene. It doesn’t react with cement. This is why we are using 0.79 g/cc (specific gravity of kerosene) in our calculation (specific gravity of water – 1g/cc)
Test Procedure:
The Flask should be free from the liquid that means it should be fully dry. Weigh the empty flask(W1)
Fill the cement on the bottle up to half of the flask (about 50gm) and weigh with its stopper (W2)
Add Kerosene to the cement up to the top of the bottle. Mix well to remove the air bubbles in it. Weigh the flask with cement and kerosene (W3)
Empty the flask. Fill the bottle with kerosene up to the top and weigh the flask (W4)
Calculation:
Specific Gravity,Specific Gravity of Cement Formula
The specific gravity of kerosene is 0.79 g/cc
Note:
- The error value will be acceptable ±0.01.
- The practical will be done within 30° C temperature.
RESIDENTIAL PLAN
#1 (40' x 80') - Click here
#2 (30' x 50') - Click here
#3 (30' x 24') - Click here
#4 (30' x 60') - Click here
#5 (30' x 70') - Click here
#6 (25' x 60') - Click here
#7 (20' x 60') - Click here
#8 (30' x 40') - Click here
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