The Bitumen Extraction Test is a commonly used method to determine the amount of bitumen present in an asphaltic pavement. This test involves using a cold solvent extraction process to calculate the percentage of bitumen content in the pavement.
The percentage of bitumen used in the construction of a flexible pavement is a critical factor in determining its properties. The durability, compatibility, and resistance to common defects such as bleeding, raveling, and aging are largely dependent on the amount of bitumen mixed with the aggregate during the pavement-laying process.
Therefore, by performing the Bitumen Extraction Test, engineers and technicians can accurately assess the amount of bitumen used in a pavement and ensure that it meets the required specifications for optimal performance and longevity.
Aim of the Test
The cold solvent extraction method is used to determine the amount of binder content, or bitumen, in an asphalt mix. This method involves using a solvent, such as trichloroethylene, to extract the binder from the mixture while it is in a cold state. The extracted binder is then weighed to determine its mass, which can be used to calculate the percentage of binder in the asphalt mix. This method is often preferred over other methods because it is relatively simple and inexpensive, and it does not require high temperatures, which can alter the properties of the binder.
Code References
- IRC: SP 11 –1988 (Appendix – 5)
- ASTM D 2172
Apparatus Required
A centrifuge is a device with a capacity of 500 grams and a sensitivity of 0.01 grams that is used for separating substances of different densities by spinning them at high speeds. It is commonly used in scientific research and medical laboratories.
A balance is an instrument used for measuring the weight of an object. The balance in question has a capacity of 500 grams and a sensitivity of 0.01 grams, meaning it can accurately measure very small differences in weight.
A thermostatically controlled oven is a device used for heating materials to a specific temperature. The oven in question has a capacity of up to 2500 degrees Celsius and is used in scientific research and industrial applications.
A beaker is a container used for holding liquids during experiments. The beaker in question is used for collecting extracted material, such as oils or chemicals, during a scientific experiment or industrial process.
Procedure of Test
To begin the extraction process, take a representative sample weighing exactly 500 grams and place it in the extraction apparatus bowl (W1). Then, add enough benzene to submerge the sample completely.
Next, take a filter paper, dry and weigh it accurately, and place it over the bowl containing the sample (B). Clamp the cover of the bowl tightly to prevent any leakage during the extraction process.
To collect the extract, place a beaker under the drainpipe of the apparatus. Allow sufficient time for the solvent to disintegrate the sample, but not more than an hour, before running the centrifuge.
Begin running the centrifuge at a slow speed and gradually increase it to a maximum of 3600 rpm. Keep the centrifuge running at the same speed until the solvent stops flowing from the drainpipe. Continue running the centrifuge until all the bitumen and benzene are drained out completely.
Once the extraction process is completed, stop the machine and remove the cover of the bowl. Add 200ml of benzene to the material in the extraction bowl and repeat the same extraction process at least three times until the extract is clear and no darker than a light straw color.
Collect the material from the bowl of the extraction machine, including the filter paper, and dry it to a constant weight in the oven at a temperature of 1050 C to 1100 C. After cooling it to room temperature, weigh the material (W2) and the filter paper (D) separately with an accuracy of 0.01grams.
Calculation and Observation
| Sl No | Observation | Sample 1 | Sample 2 | Sample 3 |
| 1 | Weight of mix taken before extraction (W1) | |||
| 2 | Weight of filter paper before extraction (B) | |||
| 3 | Weight of mix after extraction (W2) | |||
| 4 | Weight of filter paper after extraction (D) | |||
| 5 | Weight of filler collected in filter paper (B-D) =W3 |
The given formula is used to calculate the percentage of binder content in a mixture. The binder content is an important factor to consider in many fields, such as construction and materials science. The formula allows for an accurate calculation of the percentage of binder in a mixture, which can help determine the strength and durability of the final product.
It is important to understand the composition of a mixture in order to calculate the percentage of binder content accurately. The binder is the substance that holds the mixture together, and its percentage can greatly affect the properties of the mixture. Therefore, the accurate determination of binder content is crucial to ensure the desired characteristics of the final product.
The formula itself is a mathematical expression that involves the weight of the binder and the weight of the mixture. By dividing the weight of the binder by the weight of the mixture and multiplying by 100, the percentage of binder content can be calculated. This formula is widely used in various fields, and accurate calculation of the binder content can lead to improved performance and longevity of the final product.
Overall, the formula for calculating the percentage of binder content is a valuable tool in many industries. It allows for an accurate determination of the amount of binder in a mixture, which can greatly affect the properties of the final product. Understanding the composition of a mixture and accurately calculating the binder content is essential for ensuring the desired characteristics of the final product.
Report
The task is to determine the average percentage of binder content in a particular Bitumen Mix. The final result should be reported with a precision of two decimal points, rounding off to the nearest value.