This document discusses various non-destructive testing (NDT) methods used to evaluate concrete structures, including rebound hammer testing to measure compressive strength, ultrasonic pulse velocity testing to measure density and homogeneity, permeability testing to assess quality and density, and coring to directly measure compressive strength. It also outlines the use of instruments like video borescopes, corrosion analyzers, resistivity meters, eddy current devices, infrared cameras, and acoustic emission techniques to detect cracks, corrosion, and other issues. The conclusion states that NDT methods can provide strength data and assess reinforcement, cracks, corrosion, and repairs to prevent accidents.

1. NDT Tests and their importance
PRESENTED BY:-
Rajesh Kumar
Chanchal sonkar
M.Tech.-2nd sem

2. OUTLINE
NDT tests on concrete
Conclusion
REFERENCES

3. NDT tests on concrete
 Rebound Hammer:- (IS 13311(Part 2:1992)
(1) Based on principal of rebound of an elastic mass
(2) Use to measure compressive strength of concrete
(3) 4 Types available
(i)N M15-M45
(ii) L For light weight concrete, sensitive part
(iii) P Bellow M15
(iv) M Above M45

4. Ultrasonic Pulse Velocity Meter
(IS 13311(Part 2:1992)
 Use to measure ultrasonic velocity in Structure
To access density uniformity and homogeneity of
concrete
Excellent - above 4.5 km/sec
Good – 4.5 km/sec
Medium – 3.0 to 3.5 km/sec
Poor - 3.0 km/sec

5. Cut and Pullout
 To measure the compressive strength of concrete
By making hole 15 mm depth and 18 mm dia

6. Core cutter
To access for compressive strength of concrete
Core size – 50 mm to 70 mm
Length to Dia ratio – 1 to 2

7. Permeability test
• Use to measure permeability of surface coating
• To access quality of concrete, density
Very Bad > 10
Bad 1 to 10
Normal .1 to 1
Good .01 to .1
Very Good < .1

8. Video Borescope
• To view internal condition of structure By making holes

9. Corrosion Analyzer
 Based on electrochemical technique , half cell potential
 90% chance not corrosion- < -200 mv
Transient phase -200mv to -350 mv
90 % chance of corrosion. >-350 mv

10. Resistivity Meter
To assist corrosion of steel by measuring resistance of
steel wire
No corrosion R >12 Kohm.cm
Corrosion is possible R 8 to 12Kohm.cm
Corroded R< 8kohm.cm

11. Eddy Current Meter
• Used to detect crack in metal structure

12. Infra Red thermal imager
• To see thermal image of cracks point and stress point

13. Acoustic Emission Technique
• To detect crak in steel bridges in hidden location
Instrument:-
6 channel SPARTAN 2000 SYS
6 Channel MISTRAS 2001 SYS
Sensor ranging 30 khz -300 khz
PC and connecting cable

14. Digital Ultrasonic distance meter
• Used to measure length , area and volume
• Use laser beam for measuring dimensions

15. Conclusion
 NDT instrument provide strength , reinforcement bar dia
,cracks ,corrosion in bards , easy assessment to
repairing using these instrument we can prevents
accidents.

16. REFERENCES
 http://www.engineeringtoolbox.com/ndt-non
destructive-testing-d_314.html
 http://www.metso.com/pulpandpaper/mpwge
neral.nsf/webwid/wtb-111019-2256f-
eb3fd/$file/ndt.pdf
 http://www.ndted.org/AboutNDT/aboutndt.ht
m
 http://wwwpub.iaea.org/MTCD/publications/P
DF/TCS-13.pdf