Some useful concrete tests for checking the quality of concrete

Concrete Test is essential for verifying the quality of concrete based on the following points :-

1. To identify the deviation of quality of concrete that is delivered for a certain specification.
2. To ensure that there is ample strength in concrete or placing of concrete is adequate for stripping, stressing, de-propping, opening to traffic etc.
3. To ensure that the concrete has achieved enough strength for the future purpose.

Various types of tests can be initiated for verifying diverse qualities of concrete. Various tests provide results for their relevant quality of concrete. Due to high cost and time, it becomes difficult to carry all the tests at a time. So, the reasons for quality tests of concrete are very much crucial.

The most vital assessment for verifying the concrete quality is to identify the variation of concrete quality with the set specification and mix design throughout concrete mixing and positioning to make sure that the proper quality of concrete is being set at site and with checks for concrete placement in place, the quality of assembled concrete members will be as preferred.

The following tests are conducted to determine the quality of concrete: Tests on toughened concrete -

• Compressive strength (cylinder, cube, core)
• Tensile strength: Direct tension
• Modulus of rupture
• Indirect (splitting) Test
• Density
• Shrinkage
• Creep
• Modulus of elasticity
• Absorption
• Permeability Tests on Concrete
• Freeze/thaw resistance
• Resistance to aggressive chemicals
• Resistance to abrasion
• Bond to reinforcement
• Analysis for cement content and proportions
• In situ tests: Schmidt Hammer, Concrete pull-out, break-off, cones etc.
• Ultrasonic, nuclear.

Tests on fresh concrete:

• Workability Tests (slump test and others)
• Bleeding
• Air content
• Setting time
• Segregation resistance
• Unit weight
• Wet analysis
• Temperature
• Heat generation

Most of the above routine tests are based on compression tests and slump tests. It is also advantageous to carry out fresh concrete temperature and hardened concrete density determination tests.

Ref: theconstructor.org