Calculator for specific gravity of cement

Specific gravity of cement

Determination of specific gravity of given sample of cement

Aim:

Determination of specific gravity of cement as per IS 4031-(Part 11)-1988.

Equipments Required:

• Le-Chatelier Flask (Specific gravity bottle).
• Trowel.
• Measuring jar.
• Weighing balance
• Other accessories.
• Plate
• Rubber glove.

Theory:

The specific gravity of cement is the ratio of the weight of a given volume of substance to the weight of an equal volume of water. It is a number and denotes how many times a substance is heavy as water. To find the specific gravity of cement, it is required to find the weight of a certain volume cement and the weight of an equal volume of water. As cement reacts with water its specific gravity is determined with reference to a non-reactive liquid like kerosene. The specific gravity of ordinary portland cement is generally around 3.15. Equation for specific gravity, G is

\[G = \frac{{\left( {\mathop W\nolimits_2 - \mathop W\nolimits_1 } \right) \times \left( {\mathop W\nolimits_4 - \mathop W\nolimits_1 } \right)}}{{\left[ {\left( {\mathop W\nolimits_4 - \mathop W\nolimits_1 } \right) - \left( {\mathop W\nolimits_3 - \mathop W\nolimits_2 } \right)} \right] \times \left( {\mathop W\nolimits_5 - \mathop W\nolimits_1 } \right)}}\]

Where,

• W₁ = Weight of empty dry bottle in grams.
• W₂ = Weight of bottle + cement in grams.
• W₃ = Weight of bottle + Cement + Kerosene in grams.
• W₄ = Weight of bottle + Full Kerosene.
• W₅ = Weight of bottle + Full Water.

Precautions:

• Only kerosene which is free of water is to be used.
• All air bubbles shall be eliminated in filling the apparatus and inserting the stopper.
• Weighing is to be done quickly after filling the apparatus and shall be accurate to 0.1 mg.
• Precautions are to be taken to prevent expansion and overflow of the contents resulting from the heat of the hand when wiping the surface of the apparatus.

Procedure:

1. Clean and dry the specific gravity bottle and weigh it with the stopper is taken as, (W₁ in gm).
2. Fill the specific gravity bottle with cement sample at least half of the bottle and weigh with stopper is taken as, (W₂ in gm).
3. Fill the specific gravity bottle containing the cement, with kerosene (free of water) placing the stopper and weigh it (W₃ in gm) ,While doing this do not allow any air bubbles to remain in the specific gravity bottle. (W₃ in gm).
4. After weighing the bottle, the bottle shall be cleaned and dried again.
5. Then fill it with fresh kerosene and weigh it with stopper is taken as, (W₄ in gm).
6. Remove the kerosene from the bottle and fill it with full of water and weigh it with stopper is taken as, (W₅ in gm).

Table:

Sl.No	Particulars	Test No.1	Test No.2	Test No.3
1.	Weight of empty dry bottle (W1), gm
2.	Weight of bottle + cement (W2), gm
3.	Weight of bottle + Cement + Kerosene (W3), gm
4.	Weight of bottle + Full Kerosene (W4), gm
5.	Weight of bottle + Full Water (W5), gm.
6.	Specific gravity, G
5.	Average G = (G1+G2+G3)/3

Result:

Average, G=

Verification/ Validation:

The specific gravity of ordinary portland cement is around 3.15. If the difference between the three tests differ by more than 0.03, the test shall be repeated.

Conclusion:

Specific gravity of the given cement obtained as ___________.

Viva Questions:

1. Define specific gravity.
2. Why is kerosene used instead of water in the specific gravity test.
3. What is the use of specific gravity of cement ?
4. Is specific gravity of cement constant ?
5. Name the factors affecting the specific gravity of cement.

Determination of specific gravity of given sample of cement

Aim:

Determination of specific gravity of cement as per IS 4031-(Part 11)-1988.

Equipments Required:

• Le-Chatelier Flask (Specific gravity bottle).
• Trowel.
• Measuring jar.
• Weighing balance
• Other accessories.
• Plate
• Rubber glove.

Theory:

The specific gravity of cement is the ratio of the weight of a given volume of substance to the weight of an equal volume of water. It is a number and denotes how many times a substance is heavy as water. To find the specific gravity of cement, it is required to find the weight of a certain volume cement and the weight of an equal volume of water. As cement reacts with water its specific gravity is determined with reference to a non-reactive liquid like kerosene. The specific gravity of ordinary portland cement is generally around 3.15. Equation for specific gravity, G is

\[G = \frac{{\left( {\mathop W\nolimits_2 - \mathop W\nolimits_1 } \right) \times \left( {\mathop W\nolimits_4 - \mathop W\nolimits_1 } \right)}}{{\left[ {\left( {\mathop W\nolimits_4 - \mathop W\nolimits_1 } \right) - \left( {\mathop W\nolimits_3 - \mathop W\nolimits_2 } \right)} \right] \times \left( {\mathop W\nolimits_5 - \mathop W\nolimits_1 } \right)}}\]

Where,

• W₁ = Weight of empty dry bottle in grams.
• W₂ = Weight of bottle + cement in grams.
• W₃ = Weight of bottle + Cement + Kerosene in grams.
• W₄ = Weight of bottle + Full Kerosene.
• W₅ = Weight of bottle + Full Water.

Precautions:

• Only kerosene which is free of water is to be used.
• All air bubbles shall be eliminated in filling the apparatus and inserting the stopper.
• Weighing is to be done quickly after filling the apparatus and shall be accurate to 0.1 mg.
• Precautions are to be taken to prevent expansion and overflow of the contents resulting from the heat of the hand when wiping the surface of the apparatus.

Procedure:

1. Clean and dry the specific gravity bottle and weigh it with the stopper is taken as, (W₁ in gm).
2. Fill the specific gravity bottle with cement sample at least half of the bottle and weigh with stopper is taken as, (W₂ in gm).
3. Fill the specific gravity bottle containing the cement, with kerosene (free of water) placing the stopper and weigh it (W₃ in gm) ,While doing this do not allow any air bubbles to remain in the specific gravity bottle. (W₃ in gm).
4. After weighing the bottle, the bottle shall be cleaned and dried again.
5. Then fill it with fresh kerosene and weigh it with stopper is taken as, (W₄ in gm).
6. Remove the kerosene from the bottle and fill it with full of water and weigh it with stopper is taken as, (W₅ in gm).

Table:

Sl.No	Particulars	Test No.1	Test No.2	Test No.3
1.	Weight of empty dry bottle (W1), gm	57	57.1	57.05
2.	Weight of bottle + cement (W2), gm	107	107.1	106.9
3.	Weight of bottle + Cement + Kerosene (W3), gm	174	174.1	173.9
4.	Weight of bottle + Full Kerosene (W4), gm	136	136.1	136.2
5.	Weight of bottle + Full Water (W5), gm.	157	157.1	156.9
6.	Specific gravity, G
5.	Average G = (G1+G2+G3)/3

Result:

Average, G=

Verification/ Validation:

The specific gravity of ordinary portland cement is around 3.15. If the difference between the three tests differ by more than 0.03, the test shall be repeated.

Conclusion:

Specific gravity of the given cement obtained as .

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3. Third video

Blogs

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Refrence

1. Brooks, J.J & Neville A. M. (2019). Concrete Technology (2^nd ed.). Pearson Publishers Pvt Ltd.

2. Shetty, M. S & Jain, A. K. ( 2018). Concrete Technology: Theory And Practice (8^thed.).S Chand Publishers Pvt Ltd.