What does the particle density of ASTM C128 represent?

  • Thread starter goldfish9776
  • Start date
  • Tags
    Gr
However, upon the addition of water, the aggregate will displace some of the water, resulting in a lower density. In summary, the bulk density of SP Gr of ASTM C128 for fine aggregate is calculated by dividing the dry weight of the aggregate by the weight of the pycnometer filled with water plus the weight of the saturated surface dry sample minus the weight of the pycnometer filled with water and aggregate. This represents the weight of the water displaced by the aggregate (plus the weight of the pycnometer). The numerator in the calculation should also be the weight of the pycnometer with only the saturated surface dry sample.
  • #1
goldfish9776
310
1
I was told that the bulk density of SP Gr of ASTM C128 for fine aggregrate is (dry weight of aggragrate)/ ( weight of pycnometer filled with water + saturated surface dry of sample - weight of pycnometer filled with water and aggragrate )...What does the ( weight of pycnometer filled with water + saturated surface dry of sample - weight of pycnometer filled with water and aggragrate ) represent ?
 
  • #3
goldfish9776 said:
What does the ( weight of pycnometer filled with water + weight of pycnometer with only saturated surface dry [] sample - weight of pycnometer filled with water and aggragrate ) represent ?
This represents the weight of the water displaced by the aggregate (plus the weight of the pycnometer). Notice my changes in red above. Note also that the numerator in your calculation should also be "weight of pycnometer with only saturated surface dry sample."

ASTM C128 actually gives the "particle density" of the aggregate.
 
Last edited:

1. What is ASTM C128 bulk dry sp. Gr?

ASTM C128 bulk dry sp. Gr is a test method used to determine the bulk specific gravity of coarse aggregates. This measurement is important in determining the quality and properties of aggregates used in construction materials.

2. How is the bulk specific gravity of coarse aggregates determined using ASTM C128?

The bulk specific gravity of coarse aggregates is determined by filling a measure with a known volume of the aggregate, immersing it in water, and then determining the weight of the aggregate in water. This weight is then compared to the weight of an equal volume of water to calculate the bulk specific gravity.

3. What is the significance of bulk specific gravity in construction materials?

The bulk specific gravity of coarse aggregates is important because it affects the strength, durability, and workability of construction materials. It is also used in determining the amount of water needed in concrete mixes and to ensure the proper proportioning of aggregates in asphalt mixes.

4. Is ASTM C128 bulk dry sp. Gr applicable to all types of coarse aggregates?

No, ASTM C128 is specifically designed for determining the bulk specific gravity of coarse aggregates with a maximum particle size of 37.5 mm (1.5 inches). It is not applicable to fine aggregates or coarse aggregates with larger particle sizes.

5. Are there any other methods for determining the bulk specific gravity of coarse aggregates?

Yes, there are other methods such as the displacement method and the vacuum saturation method. However, ASTM C128 is the most commonly used method in the construction industry and is recognized by many regulatory agencies.

Similar threads

  • Engineering and Comp Sci Homework Help
Replies
1
Views
50K
Replies
9
Views
3K
  • Introductory Physics Homework Help
Replies
5
Views
3K
  • Chemistry
Replies
8
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
Replies
3
Views
2K
  • Special and General Relativity
Replies
20
Views
2K
  • Introductory Physics Homework Help
Replies
26
Views
4K
  • Introductory Physics Homework Help
Replies
5
Views
4K
  • Biology and Chemistry Homework Help
Replies
1
Views
6K
Back
Top