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SEMINAR REPORT ONNON DESTRUCTIVE TEST

Presented by

Timmareddy

VIII sem civil engg

under guide

prof ; RENUKASWAMY GAVAI

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INTRODUCTION

NEED FOR TESTING

VISUAL INSPECTION FOR NDT TESTING

NDT METHOD OF TESTING

CONCLUSION

CONTENTES

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The quality of product was checked & evaluated by

NDT method .

most of the materials made of concrete such as

buildings,tunnels,dams,bridges etc

NDT as ability to determine the strength &

durability of critical construction without

damaging them

The main advantages is the quality of concrete

structure is determine without damaging

INTRODUCTION

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Proposed change of usage or extension of a

structure

Acceptability of a structure for purchase

Acceptability of a structure for insurance

To test the material components without

disturbing its excites

Monitoring long-term changes in material

properties and structural performance

NEED FOR TESTING

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Visual inspection is very important to knowing structure details about any defects in concrete .to note any presences of cracking and the cracking type .

History of the structure

VISUAL INSPECTION FOR NDT TESTING

6Fig 3: Serious crack at building structure. Fig 4: Exposed bar

Fig 1: Serious cracks at bridge structure

Fig 2: Watermark indicates leak

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There are several NDT methods are applicable to concrete structure

METHOD OF NDT TESTINGS

1. Ultrasonic pulse velocity test

2. Rebound test

3. Rebar detective test

4. Rebar corrosion detective test

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Used to asses the quality and strength of in-situ

concrete in structural member.

Its used to check the compaction of

concrete,uniformity,determination of cracks

PUNDIT (portable ultrasonic NON-destructive digital

indicating tester ) from U.K

Consists of a pair of transducers (probes) of different

frequencies, electrical pulse generatet,eletrical timing

devices and cables.

It’s based on the through-transmission technique.

ULTRASONIC PULS VELOCITY TEST

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Portable Ultrasonic Nondestructive Digital Indicative

Technique (PUNDIT)

Size: 180 X 110 X 160mm

Weight 3kg

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PUNDITH METHOD OF TESTING

1. DIRECT METHOD

2. IN DIRECT METHOD

3. SEMI DIRECT METHOD

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DIRECT METHOD

SEMI-DIRECT METHOD

INDIRECT METHOD

PUNDITH METHODS

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Pulse velocity will be measured in concrete by placing “TRANSDUCERS ACROSS” the member exactly opposite to each other.

DIRECT METHOD

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INDIRECT METHOD

Pulse velocity will be measured in concrete by placing transducers on the SAME PLANE of the member

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Pulse velocity will be measured in concrete by placing transducers intermediate between those of the other two method.

SEMI DIRECT METHOD

SEMI-DIRECT TRANSMISSION OF PULSE IN R.C.DECK

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METHOD OF CALCULATION OF PULSE VELOCITY

Velocity = distance traveled / path lengthTime taken

Pulse Velocity in concrete will be represented in Km/sec.Classification of the quality of concrete on the basis of the pulse velocityPLUSE VELOCITY (KM/SEC) QUALITY OF CONCRETE

ABOVE 4.5 EXCELLENT

3.5 TO 4.5 GOOD

3.1 TO 3.5 POOR

BELOW 3.O VERY POOR

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This is quick method or assessing the quality

of concrete based on the surface hardness

indicated by the rebound number.

An higher rebound value indicates the higher

strength or surface hardness of concrete.

This equipment works based on the spring

controlled hammer mass or slides on a

plunger within a tubular housing.

REBOUND HAMMER TEST

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Fig: Rebound Hammer.Weight < 2Kg

Impact Energy = 2.2Nm

Suitability 20 – 60 MPa

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REBOUND HAMMER WORKING

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METHOD OF TESTING Rebounb hammer can be used on the

concrete surface at five different positions for assessment of surface hardness and strength estimation at site depending on the availability of exposed surface of concrete.

oHORIZONTAL

oVERTICALLY UPWARDS

oVERTICALLY DOWNWARDS

oINCLINED VERTICALLY UPWARDS

oINCLINED VERTICAL DOWNWARDS

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Fig: Testing by Rebound Hammer

by Horizantal

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POSITION OF REBOUND HAMMER - VERTICAL UPWARDS

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POSITION OF REBOUND HAMMER - VERTICAL DOWNWARDS

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DIGITAL REBOUND HAMMER

REBOUND HAMMER

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REBAR DETECTIVE TEST

The PROFOMETER 5 locates reinforcing bars,

spacing of bar, complete accuracy.

It also helps in preparing structural drawing of

the structural member in the absence of

details about the building.

This is works on electromagnetic principle

equipment consists of display unit coupled

with probes of different types

The identified concrete surface will be cleaned

such that it if free from dust, oil,

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ESTIMATION OF COVER AND MAPPING OF REBARS IN ABUTMENT

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ESTIMATION OF COVER AND MAPPING OF REBARS IN BEAM

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DISPLAY VIEW ONLY

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The method of half cell potential measurements normally involves measuring the potential of an embedded reinforcing bar.

This is usually a copper / copper sulphate, or silver /silver chloride cell

EQUIPMENTS RAE USED HALF CELL ELECTRICAL JUNCTION DEVIES VOLTMETER ELECTRICAL LEAD WIRES

REBAR CAROSSIVE

DETECTIVE TEST

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Potential difference level (m v)

Chances of rebar corroded

Less than -500 Visible evidence of corrosion

-350 to -500 95%

-200 to -350 50%

More then -200 05%

RISK OF CORROSION AGAINST THE POTENTIAL DIFFERENCES READING

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Non destructive test are relatively performed in

concrete structure

The quality of product was checked & evaluated

by NDT method without disturbing the structure

NDT now considered as a powerful method for

evaluating existing concrete structure

Cover meter is the method from which

approximate mapping of the structure can be

done

CONCLUSION

THANK YOU