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LABORATORY EXERCISE 8
BULKING OF FINE AGGREGATES
Objective
This laboratory exercise aims to determine the bulking of fine aggregaes.
Significance:
In RC structure, cement concrete is one of the most important constituent as it forms the bulk
of construction. Cement concrete can be a nominal mix or design mix. Various ingredients of
concrete mix are cement, aggregates (both fine and coarse), and water for causing hydration of
cement. Among the various ingredients of concrete, fine aggregates play a vital role in
minimizing the segregation of concrete besides reducing the voids. With this the correct
measure of fine aggregates, as per the design proportion, must be added. The proportion of
fine aggregates to be added should be measured either by weight or by volume. If measured by
weight, no corrections to the design proportions of fine aggregates need to be applied due to
bulking of sand. However, if measured by volume, then bulking of sand should be determined
and necessary corrections need to be applied to the design proportions of fine aggregates.
Equipment/Apparatus
container (beaker)
steel rule
steel rod (6mm)
graduated cylinder (250 ml capacity)
scoop or spoon
Sample
The fine aggregate sample shall be obtained in accordance with AASHTO T2 (Sampling of
Aggregates) and reduced in accordance with AASHTO T248 (Reducing Field Sample of
Aggregates to Test Size).
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Procedure:
1. Take a sample of fine aggregate
and fill the graduated cylinder up
to 200 ml graduation mark.
2. Level with the steel rule without
shaking the cylinder.
3. Transfer the sample of sand in
another container.
4. Refill the graduated cylinder with
water.
5. Pour the sample of sand in the
cylinder filled with water and stir
well so that it is thoroughly mixed
with water.
6. Allow it to settle for some time.
Note the new level of sand’s
surface and denote it as “y”.
7. Calculate the bulking of sand
using the formula
𝐵𝑢𝑙𝑘𝑖𝑛𝑔 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑎𝑛𝑑 =
200 − 𝑦
𝑥 100%
𝑦
8. Repeat the procedure for two more
samples of fine aggregates and
record the readings. The average of
the three readings is taken as the
final result.
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BULKING OF FINE AGGREGATES
DATA SHEET
Date Presented:
February 7, 2025
__________________
February 21, 2025
__________________
Submitted By:
__________________
Group No.:
__________________
Date Performed:
Data
Sample No.
Description
1
2
3
200mL
44.35%
200mL
200mL
164mL
171mL
163mL
21.95%
16.95%
22.7%
Moisture Content of Fine Aggregate, %
Volume of Loose Fine Aggregate, mL
Volume of Saturated Fine Aggregate, mL
Bulking of Fine Aggregate, %
𝐵𝑢𝑙𝑘𝑖𝑛𝑔 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑎𝑛𝑑 =
200 − 𝑦
𝑦
𝑥 100%
Average Bulking of Fine Aggregate, %
Calculations:
Moisture % =
Bulking:
𝟔𝟓𝟏−𝟒𝟓𝟏
Sample No. 1 =
Sample No. 2 =
Sample No. 3 =
𝟒𝟓𝟏
𝟐𝟎𝟎−𝟏𝟔𝟒
𝟏𝟔𝟒
𝟐𝟎𝟎−𝟏𝟕𝟏
𝟏𝟕𝟏
𝟐𝟎𝟎−𝟏𝟔𝟑
Average Bulking:
%=
𝟏𝟔𝟑
𝟐𝟏.𝟗𝟓+𝟏𝟔.𝟗𝟓+𝟐𝟐.𝟕𝟎
𝟑
× 𝟏𝟎𝟎 = 44.35%
× 𝟏𝟎𝟎 = 21.95%
× 𝟏𝟎𝟎 = 16.95%
× 𝟏𝟎𝟎 = 22.70%
= 𝟐𝟎. 𝟓𝟑
20.53%
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Observations:
In this experiment, the bulking of fine aggregate was measured by mixing 200 mL
___________________________________________________________________________
of loose sand with water and observing the volume change. The bulking percentages
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for the three samples were 21.95%, 16.95%, and 22.7%, with an average of
___________________________________________________________________________
20.53%. This means the sand's volume increased by about 20.53% when water was
___________________________________________________________________________
added. The differences in bulking percentages show that the sand’s properties, like
___________________________________________________________________________
size or moisture, can affect the results. This test helps understand how sand behaves
___________________________________________________________________________
when wet, which is important for accurate measurements in construction. The
___________________________________________________________________________
findings ensure that enough material is available for building projects.
Analysis and Interpretation of the Results:
The results show that when water is added to sand, its volume increases due to
___________________________________________________________________________
bulking. The average bulking percentage was 20.53%, meaning the sand expanded
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by about 20.5%. The difference in bulking percentages between the samples
___________________________________________________________________________
suggests that the sand had different characteristics, such as moisture content or
___________________________________________________________________________
particle size. The sample with the highest bulking percentage may have had more
___________________________________________________________________________
air spaces between particles, allowing for more expansion. This experiment highlights
___________________________________________________________________________
how moisture affects the volume of sand, which is important when calculating the
___________________________________________________________________________
amount of sand needed for construction.
Conclusion:
In conclusion, this lab experiment successfully demonstrated the bulking effect of
___________________________________________________________________________
fine aggregates when mixed with water. The average bulking percentage of 20.53%
___________________________________________________________________________
indicates a significant increase in sand volume due to moisture. This experiment
___________________________________________________________________________
provides valuable insight for construction projects, ensuring accurate material
___________________________________________________________________________
quantities are used for optimal results.
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___________________________________________________________________________
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