Grades of Bitumen

Bitumen grades are typically categorized based on their physical properties, such as viscosity, penetration, and softening point. The most common grading systems include:

1. Penetration Grade: This grading is based on the hardness of the bitumen, measured by the penetration depth of a standard needle under specified conditions. Common penetration grades include 60/70, 85/100, and 40/50. The numbers represent the penetration range in tenths of a millimeter.
2. Viscosity Grade: This system measures the bitumen’s resistance to flow at high temperatures, usually measured in centistokes (cSt). Examples include VG-10, VG-20, and VG-30.
3. Performance-Based Grade (PG): This grading system assesses the performance of bitumen under various temperature conditions and stresses. For example, PG 64-22 indicates a bitumen suitable for a maximum high temperature of 64°C and a minimum low temperature of -22°C.
4. Bitumen PMB stands for Polymer Modified Bitumen: It’s a type of asphalt binder that has been modified with polymers to enhance its properties. This modification improves the performance of the bitumen, making it more resistant to deformation, cracking, and aging, which is especially useful in heavy traffic areas and extreme weather conditions. PMB is commonly used in road construction and maintenance to extend the lifespan and durability of the pavement.

Different countries and standards may use variations of these systems. Let me know if you need details on a specific grade or system!