Non-Destructive Tests are useful for testing and evaluation of concrete strength after construction and during its lifetime. NDT tests are conducted to ensure the quality of concrete construction as per required specification for intended use. Various Non Destructive Testing Equipments for concrete strength evaluation are available. These NDT Testing equipments are useful to assess concrete construction quality.
Following are various NDT Test equipments for concrete strength evaluation:
1. Rebound Hammer:
Rebound hammer is used for testing surface strength of concrete. Rebound hammer provides rebound number after testing of concrete which is used for concrete strength estimation.
Ultrasonic pulse velocity meter is used for quality of concrete after construction. Qualities such as uniformity and homogeneity of concrete, location of internal defects in concrete, porosity, cracks.
3. Concrete Pull off Tester:
Concrete pull off testing equipment is used for testing of bond strength of concrete. This test is used for assessment of surface zone strength of concrete.
4. Pull out Testing Equipment:
There are two types of pull out tests. One is Pull out “LOK” test which is used for testing concrete during construction stage while other test Pull Out “Capo” Test is used for testing concrete after construction. Both of these tests are used for assessment of concrete surface zone strength and measures the pull out force for concrete.
5. Break off Tester:
Break off test is used for assessment of compressive strength or flexure strength of concrete. This test is continued till the concrete fails.
Windsor probe test is also used for assessment of surface zone strength of concrete. This test is done to assess the penetration resistance of concrete.
7. Micro Core Test Apparatus:
This equipment is used for testing the core (micro core) strength of concrete. This is a in-situ test for concrete structures.
8. Bond Tester:
Bond tester equipment is used for testing the bond strength between two concrete layer. Bond strength between two layers also indicates the tensile strength of concrete between two layers.
9. Maturity Meters:
Maturity meters are used for estimation of compressive strength of concrete after placement of concrete and initial setting. This test predicts the concrete strength based on the temperature of history of concrete. This tests is a measure of progress of hydration reaction of concrete. This test can be useful for strength estimation if structure has to be occupied before final setting of concrete, or the construction of structure above has to be started.