Question

In a Brazilian test, the rock specimen diameter shall preferably be:

• A. not less than NX core size (54 mm), or at least 10 times the average grain size
• B. not less than NX core size (75 mm), or at least 10 times the average grain size
• C. not less than NX core size (54 mm), or at least 20 times the average grain size
• D. not less than NX core size (75 mm), or at least 20 times the average grain size

Hint:

Standard NX core = 54 mm. Use diameter ≥ 10× grain size to ensure accurate tensile strength measurement.

Answer 1

The Correct Option is A

In a Brazilian (Indirect Tensile Strength) test, the specimen should have a diameter not less than NX core size (54 mm) and be at least 10 times the grain size to ensure uniform stress distribution and to reduce grain-size-related bias.