How do you calculate specific gravity of asphalt

Theoretical maximum specific gravity is determined by taking a sample of loose HMA (i.e., not compacted), weighing it and then determining its volume by calculating the volume of water it displaces (Figure 1). Theoretical maximum specific gravity is then the sample weight divided by its volume.

What is the specific gravity of asphalt?

Because the specific gravity of asphalt binders change with temperature, specific gravity tests are useful in making volume corrections based on temperature. The specific gravity at 15.6° C (60° F) is commonly used when buying/selling asphalt cements. A typical specific gravity for asphalt is around 1.03.

How do you calculate specific gravity of bitumen?

The specific gravity of semi-solid bituminous material, asphalt cements, and soft tar pitches shall be expressed as the ratio of the mass of a given volume of the material at 25 °C to that of an equal volume of water at the same temperature.

How do you calculate density of asphalt?

Estimate the volume of asphalt needed, using geometrical formulas and plans or measurements, including width, length, and depth (thickness). Estimate the density of the hotmix to be used. Standard density for asphalt is 145 lb/ft3 (2322 kg/m3). Multiply the volume by the density (in the same units) to get the weight.

How do you calculate effective specific gravity?

Gmm = maximum specific gravity of paving mixture (no air voids) Pmm = total loose mixture = 100% Ps = aggregate, percent by total weight of mixture (P1 + P2 + P3 + Pn) Pb = asphalt, percent by total weight of mixture. Gse = effective specific gravity of aggregate.

Why do we test specific gravity?

‌A urine concentration test provides the specific gravity of your urine. This measures your kidneys’ ability to balance water content and excrete waste. It is important in diagnosing some health conditions that impact water content in your urine.

How do you calculate specific gravity in bulk?

The bulk specific gravity of a compacted asphalt mix specimen is determined by computing the ratio of its mass in air to its bulk volume.

How is asphalt compaction measured?

The most common method is a Nuclear Density Gauge. The gauge measures compaction as the pavement is placed. Therefore, a technician can tell the roller operator if additional compaction is needed. Once the pavement is placed, core samples with laboratory analysis can also be performed to confirm the compaction levels.

How do you calculate tons of asphalt?

1. Step 1: Measure your pathway.
2. Step 2: Convert the measurements to feet.
3. Step 3: Multiply the measurements to cubic feet.
4. Step 4: Multiply the weight density of asphalt with the volume figure.
5. Step 5: Covert the amount to tons.

What are the apparatus needed in determining the specific gravity and density of asphalt?

A Pycnometer or Filter Flask which meets ASTM and AASHTO specifications is required for specific gravity determinations. Note that a Flask Adapter or Pycnometer Adapter set may also be required depending upon the model used. A thick-walled Glass Vacuum Flask can be used for weighing in the air only.

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What is the specific gravity of coarse aggregate?

The specific gravity of aggregates normally used in road construction ranges from about 2.5 to 3.0 with an average of about 2.68. Water absorption shall not be more than 0.6 per unit by weight.

What is the specific gravity of Portland cement?

Specific gravity is normally used in mixture proportioning calculations. The specific gravity of portland cement is generally around 3.15 while the specific gravity of portland-blast-furnace-slag and portland-pozzolan cements may have specific gravities near 2.90 (PCA, 1988).

What is difference between GMM and GMB?

The difference between Gmm and Gmb is volume. The weights are identical. The difference in volume is the volume of air in the compacted HMA mixture.

How do you find the specific gravity of aggregate?

1. A clean, dry pycnometer is taken and its empty weight is determined.
2. About 1000g of clean sample is taken into the pycnometer, and it is weighed.
3. Water at 270C is filled up in the pycnometer with aggregate sample, to just immerse sample.

How do you calculate percentage of bitumen in asphalt?

1. Find out the dimension (Width and thickness)
2. Calculate Volume of Asphalt = (Long * Width * Thickness) m^3.
3. Find out the density of Asphalt (2330 or 2450 Kg/m^3)
4. Calculate the quantity of Asphalt= ( Density* Volume) Kg/MTon.

What is bulk specific gravity of asphalt?

Typical values for bulk specific gravity range from 2.200 to 2.500 depending upon the bulk specific gravity of the aggregate, the asphalt binder content, and the amount of compaction. Absorption should typically be below 2 percent.

What is the difference between specific gravity and bulk specific gravity?

Relationship with Other Specific Gravities Both use the aggregate’s oven dry weight. The difference between Gsb and bulk (SSD) specific gravity is the weight of aggregate used in the calculations. The difference between these weights is the weight of absorbed water in the aggregate’s permeable voids.

What is the difference between specific gravity and unit weight?

The specific weight, also known as the unit weight, is the weight per unit volume of a material. … The terms specific gravity, and less often specific weight, are also used for relative density.

What does a specific gravity of 1.020 mean?

Normal results in adults generally range from 1.010 to 1.020. Abnormal results are generally those below 1.010 or above 1.020. In patients with certain kidney diseases, USG doesn’t vary with fluid intake and is called a fixed specific gravity.

What is a normal specific gravity?

In general, normal values for specific gravity are as follows: 1.005 to 1.030 (normal specific gravity) 1.001 after drinking excessive amounts of water.

What does a specific gravity of 1.030 mean?

Normal: 1.005–1.030 footnote 1. Abnormal: A very high specific gravity means very concentrated urine, which may be caused by not drinking enough fluid, loss of too much fluid (excessive vomiting, sweating, or diarrhea), or substances (such as sugar or protein) in the urine.

How many square meters is a ton of asphalt?

One ton of asphalt covers: 2” or 50.8 mm thick = 24 SqM.

How do you figure square yards for asphalt?

1. First, you need to obtain the square measurement using a tape measure.
2. Second, you determine the dimension of the yard in cubic meters and multiply by the depth.
3. Third, you get the volume of the yard and multiply by the density and then change the cubic meter to ton asphalt.

What is the unit weight of asphalt?

Asphalt Mixture typically weighs from 142 to 148 pounds per cubic foot (PCF) in-place.

How do you calculate tons?

Length in feet x Width in feet x Depth in feet (inches divided by 12). Take the total and divide by 21.6 (the amount of cubic feet in a ton). The final figure will be the estimated amount of tons required.

How do you convert tons to SF?

1. Multiply the length of the area by the width of the area = Square Feet.
2. Multiply Square Feet by the Depth* = Cubic Feet.
3. Divide Cubic Feet by 27 = Cubic Yards.
4. Multiply Cubic Yards by 1.5 = Tons Needed.

What is the bulk specific gravity?

Bulk Specific Gravity (also known as Bulk Dry Specific Gravity): The ratio of the weight in air of a unit volume of aggregate at a stated temperature to the weight in air of an equal volume of gas-free distilled water at the stated temperature.

How do you calculate the number of compaction passes?

Begin with a lift of 15cm and add 7.5 cm until you find the optimum lift thickness and number of passes for the given condition. One can use strip test to determine the number of passes and equipment types to achieve the required degree of compaction for the given soil type and condition.

How is optimum binder content calculated?

The optimum asphalt content is determined by judging the appearance of the asphalt through the pyrex dishes. The optimum binder content should be determined by observing the excessive mixture draindown, or filling of un-compacted air voids through the pyrex dish.

What is the principle use of specific gravity test of bituminous materials?

It is often required to know the specific gravity of straight run and cut-back bitumen for purposes of calculating rates of spread, asphaltic concrete mix properties etc. The standard specific gravity test is carried out at a temperature of 250C.

What is true specific gravity?

4.1 The true specific gravity of a material is the ratio of its true density, determined at a specific temperature, to the true density of water, determined at a specific temperature. Thus, the true specific gravity of a material is a primary property which is related to chemical and mineralogical composition.