Condition Survey, Evaluation & Damage Assessment

1. Condition Survey, Evaluation
& Damage Assessment
Wasim Shaikh
AIKTC, New Panvel.

2. Objectives of Condition Survey:
• The objectives of Condition survey of a building are as following
• To identify causes of distress and their sources.
• To assess the extent of distress due to corrosion, fire, earthquake or another
reason.
• To asses residual strength of structure.
• To rehabilitate the structure if needed.
• To Prioritise the distress element according to the seriousness for the repairs
• TO select and plan the effective remedy

3. Diagnostic methods & analysis
• Destructive
• semi-destructive
• Non-destructive methods

4. Non-destructive methods
• Rebound Hammer test
• Ultra-sonic pulse velocity test
• Carbonation test
• Chloride test
• Core cutting test
• Corrosion analysis by half-cell potentiometer

5. Rebound Hammer test (Schmidt hammer)

6. Working of Rebound Hammer
• Indian code IS: 13311(2)-1992
• Based on the principle that the rebound of an elastic mass depends
on the hardness of the concrete surface against which the mass
strikes
• To determine the compressive strength of the concrete by relating the
rebound index and the compressive strength
• To assess the uniformity of the concrete
• To assess the quality of the concrete based on the standard
specifications
• To relate one concrete element with other in terms of quality

7. Quality of Concrete for different values of
rebound number

8. Advantages of Rebound hammer tests are:
• Apparatus is easy to use
• Determines uniformity properties of the surface
• The equipment used is inexpensive
• Used for the rehabilitation of old monuments
The disadvantages of Rebound Hammer Test
• The results obtained is based on a local point
• The test results are not directly related to the strength and the deformation
property of the surface
• The probe and spring arrangement will require regular cleaning and maintenance
• Flaws cannot be detected with accuracy

9. Ultrasonic Testing of Concrete

10. Working of Ultrasonic pulse velocity test
• Ultrasonic pulse velocity test consists of measuring travel time, T of
ultrasonic pulse of 50 to 54 kHz
• Higher the elastic modulus, density and integrity of the concrete,
higher is the pulse velocity.

11. Arrangement of Transducer and Receiver

12. Results of UPV test

13. Additional Interpretations

14. Factors affecting pulse velocity
• Path length.
• The influence of path length will be negligible provided it is not less
than 100mm
• Pulse velocity will not be influenced by the shape of the specimen
• Presence of reinforcement steel. (Higher density)
• Moisture content of the concrete. (Increase in velocity)

15. Carbonation test
0.2% solution of the phenolphthalein

16. Corrosion analysis by half-cell potentiometer

17. Corrosion analysis by half-cell potentiometer
Half – cell potential ( mv) % chance of corrosion activity
Less than - 200 10%
Between – 200 to – 350 50%
above – 350 90%

18. Pull out test

19. Pull out test

20. Pull out test

21. Factors Affecting the Concrete Pull Out Test:
• The arrangement of the embedded insert.
• The dimensions of bearing ring.
• The depth of embedment
• The type of aggregates uses in concrete.

22. Use of Concrete Pull Out Test
• To determine the strength of concrete for carrying out post- tensioning
operations.
• To Measure the time for removal of forms work based on the actual
strength of the in-situ concrete; or
• To terminate the curing of concrete based on the targeted strength
achievement.
• To estimate the strength of concrete in existing construction.

23. Pull Off Test

24. Pull Off Test

25. Pull Off Test

26. Concrete core cutter test

27. Concrete core cutter test

28. Use of Core Cutter test
• Strength and density determination
• Depth of carbonation of concrete
• Chemical analysis
• Water or Gas permeability
• Chloride permeability test

29. Chloride Content Test For Concrete
• What is Chloride Attacks?
It destroys that protective layer and corrosion starts taking place
resulting in subsequently reducing of strength the strength,
serviceability, and aesthetics of the structure

31. Procedure of Chloride Content Test
• Rapid Chloride Test (RCT)
• Chemical Analysis.
• Rapid Chloride Test (RCT)
• It works like a chloride battery
• Mix the 1.5gm sample with a special chloride extraction liquid.
Measure the electrical potential of the liquid by the chloride ion
selective electrode.

32. Cover Meter Test

33. Cover Meter Test

34. Concrete endoscopy

35. Concrete endoscopy
• Concrete pipes
• Sewer Lines,
• Culvert
• Cavity walls,
• Air ducts, Vents,
• Chimneys,
• Ceiling, roof and floor voids,
• Water tanks,
• Heritage structures,
• Timber structures,
• Concrete or Masonry structures with large voids

36. Concrete crack measurement
• Direct measurements
• Visual Examination of Concrete Cores
• Impact Echo
• Ultrasonic Pulse Velocity

37. Direct measurements

38. Direct measurements

39. Microwave image processing

40. Impact Echo