UNIVERSITY OF SAN CARLOS
Name: Jasmin S. Arquillano Group 2 Date: August 12, 2014
Schedule: 8:30-11:30 AM (Tuesday) Instructor: Engr. Kathrina Marie I. Malinao
SPECIFIC GRAVITY AND ABSORPTION I. OBJECTIVE

To determine the Apparent, Bulk (Dry), Bulk (SSD) specific gravity and the absorption in percentage of the coarse and fine aggregate sample

II. PROCEDURE WITH PICTURES

COARSE AGGREGATES

1. Approximately five kilograms of the coarse aggregate sample was taken by method of quartering. The 5 kg coarse aggregate sample was sieved by the 3/8” sieve and the materials passing through were discarded. (Figure 1)

2. The sample coarse aggregate was washed thoroughly with water to remove dust and other materials coating the individual aggregate and the sample was soaked under water for 24 hours. (Figure 2)

3. The soaked aggregates were removed and each aggregate was wiped to saturated surface dry (SSD) condition. (Figure 3)

4. The SSD weight in air (B) of aggregate to the nearest 0.1 gram was obtained. This was done quickly to prevent evaporation.

5. The weight of the wire mesh basket was determined. The coarse aggregate sample was placed in the wire mesh basket and its weight in water (C) was determined. The weight of the wire mesh basket in water was subtracted. (Figure 4)

6. The wet aggregate was placed inside the oven at a temperature not exceeding 110°C and the constant oven dry weight (A) was determined. (Figure 5)

7. From the data obtained, the specific gravity and absorption as defined below were solved:

a) Apparent Specific Gravity = AA-C

b) Bulk Specific Gravity (Dry) = AB-C

c) Bulk Specific Gravity (SSD) = BB-C

d) Absorption = B-AA*100
Figure 5. The sample coarse aggregates removed from water and set for oven-drying
Figure 4. The coarse aggregates with the wire mesh basket was weighed under water
Figure 3. Each aggregate was wiped change its state to a Saturated Surface Dry condition
Figure 1. Coarse aggregates sieved by the 3/8 ” sieve
Figure 2. Coarse aggregates washed with running water and soaked for 24 hours

FINE AGGREGATES

1. Approximately one kilogram of the fine aggregate sample was taken by method of quartering.

2. The fine aggregate sample was placed in a pan covered with water and was stood for 24 hours. (Figure 1)

3. The 1 kg sample was brought to saturated surface dry condition with the use of a blower. (Figure 2)

4. 500 grams of the SSD fine aggregate was taken and the exact weight of the SSD fine aggregate was recorded as (D).

5. The specific gravity bottle was filled with water until the 800 ml mark and the weight of the specific gravity bottle plus water in grams was recorded as (B). The water temperature was set to be about 23±1.5°C.

6. Some of the water of the specific gravity bottle was removed but 200 ml was retained and the 500 g SSD fine aggregate was added into the bottle. Enough water was added to establish the level to the 450 ml mark. (Figure 3)

7. The specific gravity bottle was rolled on a flat surface to eliminate entrapped air before more water was added up to the 800 ml mark. The weight of saturated aggregate plus water plus specific gravity bottle was recorded as (C).

8. The contents of the bottle were placed in a pan and placed inside the oven. All aggregates were washed out of the bottle by the use of tap water. The oven dry weight (A) was obtained after 24 hours.

9. From the data obtained, the specific gravity and absorption as defined below were solved:

a) Apparent Specific Gravity = AB+A-C

b) Bulk Specific Gravity (Dry) = AB+D-C

c) Bulk Specific Gravity (SSD) = DB+D-C

d) Absorption = D-AA*100
Figure 4. Fine aggregates removed from the bottle and placed in a pan before oven-drying
Figure 3. 500 grams of fine aggregates added to the specific gravity bottle with 200 ml water and bottle was filled until the 800 ml mark
Figure 2. Fine aggregates brought to Saturated Surface Dry condition
Figure 1. Fine aggregates soaked for 24 hours

III. TABULATIONS OF DATA

COARSE AGGREGATES

Weight of SSD Aggregate in Air, g (B) | 3768.1 | Weight of Saturated Aggregate in Water, g (C) | 2305.0 | Weight of Oven Dry Aggregate, g (A) | 3681.9 | | Apparent Specific Gravity | 2.6741 | Bulk Specific Gravity (Dry) | 2.5165 | Bulk Specific Gravity (SSD) | 2.5754 | Absorption, % | 2.3419 |

a) Apparent Specific Gravity = AA-C = 3681.9 g3681.9 g - 2305.0 g

b) Bulk Specific Gravity (Dry) = AB-C = 3681.9 g3768.1 g - 2305.0 g

c) Bulk Specific Gravity (SSD) = BB-C= 3768.1 g3768.1 g - 2305.0 g

d) Absorption = B-AA*100 = 3768.1 g - 3681.9 g3681.9 g*100

FINE AGGREGATES

Weight of SSD Aggregate in Air, g (D) | 500.0 | Weight of Sp. Gr. Bottle + Water, g (B) | 1383.5 | Weight of Sp. Gr. Bottle + Water + Saturated Aggregate, g (C) | 1683.0 | Weight of Oven Dry Aggregate, g (A) | 460.1 | | Apparent Specific Gravity | 2.8649 | Bulk Specific Gravity (Dry) | 2.2948 | Bulk Specific Gravity (SSD) | 2.4938 | Absorption, % | 8.6720 |

a) Apparent Specific Gravity = AB+A-C = 460.1 g1383.5 g + 460.1 g - 1683.0 g

b) Bulk Specific Gravity (Dry) = AB+D-C = 460.1 g1383.5 g +500.0 g - 1683.0 g

c) Bulk Specific Gravity (SSD) = DB+D-C = 500.0 g1383.5 g + 500 g- 1683.0 g

d) Absorption = D-AA*100 = 500g - 460.1 g460.1 g *100

IV. INTERPRETATION OF RESULTS

V. CONCLUSION