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Bitumen penetration test

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 The penetration test for bitumen determines its consistency by measuring how deep a standard needle penetrates the material under specific conditions of temperature, time, and load. This test, performed at 25°C with a 100-gram weight over 5 seconds, helps classify bitumen into grades like 30/40, 60/70, or 80/100. These grades indicate the hardness or softness of the bitumen, which is critical for its application in road construction and other industrial uses.





During the test, the bitumen sample is heated, poured into a container, and cooled under controlled conditions to ensure uniformity. The sample is then maintained at a constant temperature in a water bath. When the needle is applied, its penetration depth (measured in tenths of a millimeter) reflects the material's hardness or softness. Softer bitumen with higher penetration values is typically used in colder climates to prevent cracking, while harder grades with lower penetration values are better suited for high temperatures or heavy loads.

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