Question

Bitumen grade 80/100 indicates that under the standard test conditions, the penetration value of bitumen would vary from:

• A. 0.08 mm to 0.1 mm
• B. 80 mm to 100 mm
• C. 0.8 mm to 1 mm
• D. 8 mm to 10 mm

Hint:

In penetration grading, the number represents tenths of a millimeter of penetration at 25°C under 100 g load for 5 seconds.

Answer 1

The Correct Option is B

Step 1: Understand Bitumen Penetration Grade.
The penetration test quantifies bitumen's hardness/softness by measuring the depth (in tenths of a millimeter) a standard needle penetrates under specified conditions.

Step 2: Apply Specified Grade.
Bitumen grade 80/100 signifies a penetration value range of 80 to 100 tenths of a millimeter, equivalent to 8.0 mm to 10.0 mm.

Step 3: Correlate with Options.
Option (B) is the accurate selection: 80 mm to 100 mm (expressed in tenths of a mm, or penetration units).

Step 4: Finalize.
Consequently, the penetration value for 80/100 grade bitumen is 80 to 100 (in 0.1 mm units), corresponding to option (B).