Question

What are the different Asphalt Tests at least 5 Tests

Format

1. Name of Test

Reference

Objective

Materials and Equipment

Procedure

THANK YOU we were asked to describe 20 Tests and I have done 12 so far.

To the person who will help. SUPER THANK YOU

Answer 1

1. PENETRATION TEST

Reference:

     Highway Engineering by S.K. Khanna, C.E.G. Justo

Objective:

      To determine the hardness or softness of asphalt by measuring the depth in tenth of a millimeter to which a standard needle will penetrate vertically in five seconds.

Materials and Equipments:

a. Penetrometer – It consists of a needle assembly with a total weight of 100 g and device for releasing and locking in any position.

b. A graduated dial to read penetration values to 1/10th of a millimeter.

Procedure

a. The asphalt is softened to a pouring consistency and stirred thoroughly.

b. Pour the asphalt into containers to a depth at least 15 mm in excess of the expected penetration.

c. The sample containers are placed in a temperature controlled water bath at a temperature of 25oC for 1 hour.

d. The sample with container is taken out and the needle is arranged to make contact with the surface of the sample.

e. The initial reading is taken and the needle is released for 5 seconds.

f. The final reading is taken on dial gauge.

g. The difference between the initial reading and final reading gives the penetration value.

h. After the test the needle is disengaged and wiped with benzene and dried.

i. The test is repeated for at least three penetration value on this sample by testing at distances of at least 10 mm apart.

j. The depth penetration is reported in 1/10th millimeter units. The average of these three values gives the required penetration value of the sample.

2. DUCTILITY TEST

Reference:

     Highway Engineering by S.K. Khanna, C.E.G. Justo

Objective:

      To determine ductile property of the binder. That is to measure the adhesive property and its ability to stretch.

Materials and Equipments:

a. Ductility machine with a pulling device at a pre-calibrated rate.

b. Two clips

Procedure

a. The asphalt sample is heated and poured in the mould assembly placed on a plate.

b. The sample along with the moulds are cooled in air and then in water bath maintained at 270C.

c. The excess asphalt material is cut and surface is leveled using a hot knife.

d. The mould assembly containing sample is replaced in water bath of the ductility testing machine for 85 to 95 minute.

e. The pointer is adjusted to zero.

f. The distance up to the point of breaking of thread is reported in centimeters as ductility value.

g. The ductility of asphalt varies from 5 to 100 for different bitumen grades.

3. SOLUBILITY TEST

Reference:

     Highway Engineering by S.K. Khanna, C.E.G. Justo

Objective:

      To determine the Solubility of asphalt in solvents like carbon disulphide and carbon tetrachloride..

Materials and Equipments:

a. A sample of about 2 g.

b. A solvent od about 100 ml

c. Filter for filtering the solution.

d. Weighing machine.

Procedure

a. A sample of about 2 g of asphalt is taken.

b. It is dissolved in a solvent of about 100 ml.

c. The solution is the filtered and the insoluble materials retained on filter is washed, dried and weighed.

d. It is expressed as a percentage of original sample.

e. The insoluble material should be preferably less than 1 percent.

f. In solubility test with carbon tetrachloride, if back carbonaceous residue is over 0.5 percent, the asphalt is considered to be cracked.

4. SOFTENING POINT TEST

Reference:

     Highway Engineering by S.K. Khanna, C.E.G. Justo

Objective:

      To determine the softening point of asphalt sample. The softening point is the temperature at which the substance attains a particular degree of softening under specified condition of test.

Materials and Equipments:

a. A brass ring.

b. A steel ball

c. A container for testing

d. A small metal plate

Procedure

a. A brass ring containing test sample of asphalt is suspended in liquid like water or glycerine at a given temperature.

b. A steel ball is placed upon the asphalt sample.

c. The liquid medium is the heated at a temperature of 5oC per minute.

d. The temperature at which the softened asphalt touches the metal placed at a specified distance below the ring is recorded as the softening point of the sample.

e. Hard grade asphalt possess higher softening point than soft grade asphalt.

5. VISCOSITY TEST

Reference:

     Highway Engineering by S.K. Khanna, C.E.G. Justo

Objective:

      To determine the viscosity of the given asphalt sample.

Materials and Equipments:

a. Orifice type viscometer.

b. Given asphalt sample.

Procedure

a. Take 50 ml of asphalt sample.

b. This sample is allowed to flow from a cup through a specified orifice under standard test conditions and specified temperature.

c. Note the time taken by the sample to flow through the orifice of the viscometer.

d. This time gives the measure of viscosity.

e. If the time required to flow is higher, the viscosity will be higher.