The test determines the bitumen content in a bituminous mixture by cold solvent extraction.
tools and solvents
- centrifuge equipment
- Take a representative sample of approximately 500 g, weigh it properly and place it in the bowl of the extraction apparatus (W.)1,
- Cover the sample with commercial grade trichloroethylene.
- Allow the mixture to stand for about an hour before starting the centrifugal machine.
- Weigh the dry filter ring and then fit it over the edge of the bowl. Close the cover of the bowl tightly.
- Place a beaker under the drain to drain.
- The machine is slowly rotated and then the speed is gradually increased to a maximum of 3600 rpm. The motion is maintained until the solvent stops flowing through the drain.
- The machine is allowed to stop, 200 ml of solvent is added and the above process is repeated. Several 200 ml solvent additions (not less than three) are used until the extract is clear and darkened to a light straw color.
- Remove the fitter ring from the bowl, first in the air and then in the oven. dry on0c to a constant weight, and weigh it.
- Withdraw the fine material that has passed through the filter by centrifuging. Wash and dry the material to a constant weight as before.
Calculate the percentage of binder in the bituminous mix sample as follows:
percentage of binder = [W1 – (W2 + W3 + W4) /W1] x 100
woo1 = weight of the sample, g
woo2 = weight of the sample after extraction, g
woo3 = weight of the fine material obtained from the extract, g
woo4 = increase in the weight of the filter ring, g
Record all test data in a form as shown below.