Indirect Tension Test of Hardened Concrete (as per Indian Standard)

Indirect Tension Test of Hardened Concrete (as per Indian Standard)

Key Points:

1. Purpose:

   • To determine the tensile strength of hardened concrete.

2. Test Method:

   • Known as Split Cylinder Test or Brazilian Test.
   • Involves applying compressive load to a concrete cylinder placed horizontally.

3. Standards:

   • Conducted as per the Indian Standard (IS).

4. Formula:

   • Tensile Strength (T) is calculated using: $T=\frac{2P}{\pi LD}$ Where,
     • $P$ = Maximum Load applied (N)
     • $L$ = Length of the cylinder (mm)
     • $D$ = Diameter of the cylinder (mm)

5. Specimen Preparation:

   • Concrete cylinders typically of dimensions 150 mm diameter and 300 mm height.
   • Cured and aged as per IS recommendations.

6. Procedure:

   • Place the cylinder horizontally in the compression testing machine.
   • Apply load continuously without shock until failure.
   • Record the maximum load at failure.

7. Calculations:

   • Using the P (maximum load) from the test, calculate the tensile strength using the provided formula.

8. Observations:

   • Note any unusual failure patterns.
   • Record environmental conditions during the test.

9. Significance:

   • Provides an indirect measure of tensile strength which is critical for assessing the load-carrying capacity and durability of concrete structures.

10. Notes:

    • Ensure that the loading is applied uniformly across the specimen.
    • Make sure that the specimen is properly aligned in the testing apparatus.

Practical Tips:

• Always verify that testing machine calibration is up-to-date.
• Handle samples with care to avoid introducing flaws that could alter test results.
• Review IS standards regularly to ensure adherence to updated protocols.