Needless to mention that bitumen 60/70 is a black, pasty material that has application in moisture insulation and asphalt construction.
Technically, there are different types of bitumen, each of which has a specific application. However, bitumen 60/70 is the most applicable type.
Chemically speaking, bitumen is a hydrocarbon black to dark brown in color that dissolves completely in carbon sulfide and carbon tetrachloride.
Besides, bitumen is solid at ambient temperature. But as the temperature rises, it becomes soft and then liquefies.
The great use of bitumen is due to the existence of two major features of this material;
- Being waterproof
- Adhesion of the substance
How to determine bitumen specifications?
- Degree of penetration: The degree of the penetration test determines the hardness of bitumen.
In this experiment, a standard needle penetrates the bitumen at a temperature of 25 degrees for 5 seconds under the effect of a 100 g load.
The amount of penetration in terms of tenths of a millimeter is the degree of penetration.
To be more specific, the lower the degree of penetration, the harder the bitumen. Bitumen 60/70 is a good example in this regard.
Gravity: The higher the bitumen is; the more solid properties it shows.
They measure this characteristic of bitumen by C-bolt fiorel device or kinematically.
- Flammability: The degree of ignition is the temperature that if the bitumen reaches that temperature,
the gases emitted from it ignite as the flame approaches and a flame forms on its surface.
Additionally, the maximum temperature at which bitumen
gets warm at the project depends on the degree of ignition.
- Weight loss: Weight loss of bitumen at high temperatures is due to the evaporation of some of its oils and petroleum compounds.
This characteristic is also one of the important properties of bitumen.
In general, we measure the weight loss of bitumen in the oven at 163 ° C for 5 hours.
- Ductility: If we draw a sample of bitumen with a cross-sectional area of 1 cm2 at a speed of 5 cm/min,the amount of increase in sample length before
the bituminous property of the bitumen tears, is the ductility test of bitumen.
- Degree of purity: We know that the solvent of bitumen is tetrachloride, carbon, and sulfur carbon.
Therefore, if we dissolve a sample of bitumen in any of these materials, its impurities remain,
and from there we can determine the degree of purity of the bitumen.
Mathematically, the degree of purity is: (weight of bitumen sample) ÷ [(weight of impurity) – (weight of bitumen)].