Test for Density of Hydraulic Cement
Purpose
Determination of the density of hydraulic cement in connection with the design of Portland cement concrete mixtures
Equipment and Materials
- Standard Le-Chatelier Flask as shown below
- Heavy rubber pad about 12 in. × 12 in. square
- Lead ring weight to fit around stem of the flask
- Funnel
- Thermometer
- Portland cement
- Kerosene
Test Procedure
- Fill the flask with kerosene to a mark on the stem between the 0 and the 1 cm mark. Dry the inside of the flask if there are any drops above the liquid level.
- Place the flask in a constant temperature bath and record the initial height of the kerosene in the flask. The constant temperature bath should be maintained at a temperature such that its temperature variation between the initial and final readings within the flask does not vary by more than 0.2°C.
- Carefully introduce about 64 grams of cement, weighed to the nearest 0.1 grams. Try to avoid the cement adhering to the inside of the flask or sticking to the neck. The cement should be introduced slowly through a funnel. Place the stopper on the flask.
- Remove the flask from the bath and place it on the rubber mat. Take off the lead weight and manipulate the flask on the mat so as to remove all air bubbles from the flask.
- Return the flask to the bath and check the temperature within the flask. If it is within 0.2°C of the original temperature inside the flask, take the final reading.
Calculation
Density of hydraulic cement is calculated using following formula
Density, p = mass of cement/displaced volume
Conduct the density determination on two samples of cement. If they do not differ by more than 0.03 g/cm3, take the average. Otherwise, run three additional determinations until a pair of valves are obtained within 0.03 g/cm3.
Record the readings and complete the following data sheet.
Specimen Numbers |
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1 |
2 |
3 |
4 |
|
Initial bath temp., °C | ||||
Final height, cm | ||||
Initial height, cm | ||||
Displaced volume, cm3 | ||||
Final bath temp., °C | ||||
Specific gravity = 64grams/displacement, cm3 | ||||
Average specific gravity of accepted specimen result = |
Why 64 gms only? Why can’t be less ?
good article.
density is 1400 kg/m3 & specific gravity 3.15 approx.
what will u say this test
I like all articles of physical testing of cement.
good aricle, i like it