how to calculate % voids in course aggregrate

by Mr. Salvador Murphy 9 min read

And percentage of voids present in coarse aggregate is calculated with the help of specific gravity of coarse aggregate and their Loose bulk density by the following formula % of voids = {(Gs _R)/Gs}×100. Where Gs = specific gravity of coarse aggregate and their value is 2.65. R = loose bulk density of coarse aggregate = 1.337 kg/L. Putting all this values in formula we get % of voids = {(2.65 _ 1.337)/2.65}×100 % of voids = (1.313/2.65)×100 % of voids = 0.495×100. Hence % of voids of ...

Uncompacted void content is computed as the difference between the volume of the cylindrical measure and the absolute volume of tho coarse aggregate collected in the measure (Based on bulk dry specific gravity as determined by AASHTO T85).

Full Answer

How to calculate the percentage of voids present in coarse aggregate?

And percentage of voids present in coarse aggregate is calculated with the help of specific gravity of coarse aggregate and their Loose bulk density by the following formula How many shingles do i need for a 12×16 shed…

What is a void percentage?

The percentage of space or voids between the individual particles and in a unit volume of the aggregate mass is known as a void percentage.

What are the voids in unit volume of aggregate?

Voids in unit volume of aggregate are the space between particles in an aggregate mass not occupied by solid minerals. The bulk density values determined based on this test can be used for many methods of selecting proportions for concrete mixtures.

What is the condition of sample aggregate for voids?

The voids in aggregate will be reported as a percentage to the nearest whole number. The condition of sample aggregate at the time of test shall be stated, that is (a) oven dry, (b) saturated and surface dry, or (c) with a given percentage of moisture.

How do you calculate aggregate void?

Voids in unit volume of aggregate are the space between particles in an aggregate mass not occupied by solid minerals....3. Cylindrical Metal Measure.Nominal Maximum Size of Aggregate, mmCapacity of Measure, m^3 (L)750.028 (28)1000.070 (70)1250.100 [100]3 more rows•Nov 23, 2019

How do you find voids?

Divide the weight by the volume (1,000 ml) to find the density of the sand. For example, if the sand weighs 1,500 grams, the density is 1.5. Multiply the voidage by the volume of the dry sand to find the volume of the void. With 1,000 ml of dry sand and a voidage of 0.4, you have a void volume of 400 ml.

How is void space calculated?

To calculate the void ratio we must first calculate the volume of solids. Then we can find the volume of voids by subtracting the volume of solids from the total volume.

What is the void ratio in aggregates?

In soil mechanics, the void ratio describes the relationship between the volume of voids, or spaces, in the soil or aggregate to the volume of solid constituents, or grains. Algebraically, e = Vv /Vs, where e represents the void ratio, Vv represents the volume of voids and Vs represent the volume of solid grains.

How do you calculate the void content of concrete?

This sample calculation includes 6-10 mm size of aggregates with 375 kg/m3 cement content, 0.3 w/c ratio. The values below are the average of 3 cubes. (1.12/(1*1000))) T = 2531 kg/m3. Void content (%) = ((2531-1560)/2531)*100 = 38.4%.

How do you calculate the void ratio of concrete?

Volume of water collected in container is measured and it is equal to the volume of voids in cube, using it and volume of Pervious Concrete cube, void ratio is found out. 7. Void ratio = volume of voids/volume of cube x 100.

How do you calculate porosity and void ratio?

The Void ratio of soil given the porosity formula is defined as the relationship between void ratio and porosity of soil sample and is represented as e = (η/(1-η)) or Void ratio = (Porosity of soil/(1-Porosity of soil)). Porosity of soil is the ratio of the volume of voids to the volume of soil.

What is the void volume?

Void volume refers specifically to the volume of the liquid phase contained inside a column. The same term is sometimes also used informally to refer to the volume of a cavity in the column/tubing or fittings. Void volume is also known as dead volume.

When porosity is 50% the void ratio is?

Porosity is defined as the ratio of the volume of voids to the total volume of the soil. So porosity is always less than the void ratio. Here the void ratio is 0.5, so the porosity should be less than 50% i.e. 33%.

What percentage is void?

The percentage of voids (V %) was calculated by using the formula Vv/(Vv+VM)×100.

What is the maximum void ratio?

The maximum void ratio is 0.91 for a simple cubic packing of monosize spheres. The maximum void ratio for a packing of randomly arranged monosize spheres is about 0.70–0.80 (Dullien, 1992). The particle shape has noteworthy influence on the maximum void ratio of a packing.

What is void content?

Void Content measures the voids in reinforced polymers and composites. Information on void content is useful because high void contents can significantly reduce the composites' strength. Monitoring lot-to-lot void contents can also act as a measure of the consistency of the composites' manufacturing process.

Apparatus

Sample Preparation

  1. The size of the test sample ranges from 125% to 200 % of the amount required to fill the measure.
  2. Dry the aggregate sample to constant mass in an oven at 110±5 °C.
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Determination of Volume of Measure

  1. Evaluate the mass of the plate glass and measure the nearest 0.05 kg.
  2. Place a thin layer of grease on the rim of the measure to prevent leakage of water.
  3. Fill the measure with water and cover it with the plate glass in a manner to remove bubbles and excess water.
  4. Determine the mass of the water, plate glass, and measure to the nearest 0.05 kg.
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Test Procedure

  1. Take the weight of the empty measure (W) to the nearest 0.05kg, as per procedure provided above.
  2. Fill the measure to in three layers and compact the aggregate in three layers using one of the three methods based on the aggregate size.
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Calculations

  • 1. Calculation of Compacted Bulk Density of aggregate
    Bulk density (M)= (G-T) / V Equation 3 Or Bulk density (M)= (G-T) / F Equation 4 where: M: bulk density of the aggregate, kg/m^3, G: mass of theaggregate plus the measure, kg, T: mass of themeasure, kg, V:volume of the measure, m^3, F: factor for measure, m^3, computed from equa…
  • 2. Void Content
    Calculatethe void content in the aggregate using the bulk density determined by eitherthe rodding, jigging, or shoveling procedure, as follows: %Voids= 100[(SxW)-M]/ (SxW) Equation 6 where: M: bulk density of the aggregate, kg/m^3, S:bulk specific gravity W:density of water, 998 kg/m^3. Re…
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