Non destructive testing in civil engineering

This presentation provides info. on some of the basic NDT tests

1. NON-DESTRUCTIVE TESTING IN CIVIL ENGINEERING G.V.Manoj Kumar U.Maadaswamy RMK ENGG. COLLEGE

2. OBJECTIVE Assessment of existing structure for rehabilitation planning Detection of cracks, voids and other imperfections in the material Monitoring changes in the concrete with the passage of time

3. Non-destructive testing Is a form of testing to be carried out on various construction members and materials without causing any permanent damage to them . Does not permanently alter the article being tested

4. Difference between: Destructive testing Non-destructive testing Carried out until specimen’s failure will render the part unusable for its intended purpose Does not destroys the test specimen  after testing, allow the part to be used for its intended purpose

5. NDT-methods Visual inspection(VI) Liquid (dye) penetrant test Magnetic particle inspection(MI) Ultrasonic testing Radiography(X-ray) S chmidt rebound hammer

6. Visual inspection Oldest non-destructive testing method can successfully detect the unacceptable surface discontinuities cheap and reliable testing method

7. Liquid (Dye) penetrant test To detect surface-breaking discontinuities in all non-porous materials (metals, plastics, or ceramics). It is based  upon the principles of capillary action where  liquid penetrates into a cavity. Fast, economical and widely used method

8. Magnetic particle inspection Used to detect defects on the surface or near to the surface . Generate magnetic flux in article to be examined . The particles are often colored and usually coated with fluorescent dyes that are made visible with a hand-held ultraviolet (UV) light

9. Magnetic flux concentration

10. Ultrasonic testing Detect both internal and surface defect in sounding conducting material . Any change in acoustic impedance produces ultrasonic reflection or echo

11. Ultrasonic testing is done for the concrete

12. Ultrasonic testing machines

13. Radiography (X-ray) Radiography uses X-rays and gamma-rays to produce a radiograph of a specimen shows any changes in thickness, defects (internal and external) to obtain permanent image of surface and sub-surface discontinuities

14. Radiography test on a concrete beam

15. Rebound hammer Measures the rebound of a spring-loaded mass  hammer will hit the concrete and  rebound is dependent on the hardness of the concrete  The Schmidt hammer is an arbitrary scale ranging from 10 to 100 .

16. Procedure of the test

17. Suitability of testing Ultrasonic testing-sub surface, interstitial Magnetic particle inspection-surface, sub surface discontinues Dye penetrant test-surface-breaking defects in all non-porous materials Radiographic testing-surface, sub-surface defects

18. NDT- Benefits Sample - available afterwards for repeat or additional tests. E nables further use of work piece. Provides cost benefits. Enables comparison to standard and established results. Enables maintenance of statistical data for future interpretation.

19. Uses of NDT Flaw Detection and Evaluation Leak Detection Location Determination Dimensional Measurements Structure and Microstructure Characterization Estimation of Mechanical and Physical Properties

20. C onclusion Non-destructive testing is not only economical but gives very unique results Involves very less time when compared to universal testing machine

21. “KNOWING IS NOT ENOUGH, WE MUST APPLY WILLING IS NOT ENOUGH, WE MUST DO” Thank you!!!