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- since 1996 -

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Application of the newest technologies, such as air-coupled ultrasound, digital instrumentation, signal processing, and transducer technology.

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Technical Discussions
Rolf Diederichs
Director,
NDT.net, Germany, Joined Nov 1998, 604

Rolf Diederichs

Director,
NDT.net,
Germany,
Joined Nov 1998
604
03:07 Feb-18-2003
How to detect cracks in dams

On behalf of a reader I post this message:
I am not sure if UT could work, but what about GPR or IRT?
------
Dear Mr. Diedericks,

We have divers that do maintenance and repair dams underwater. I was asked if there is an acoustical mean (ultrasound or else) that could be used underwater to detect cracks in dams as a preventive measure.

Thank you for paying attention to my request.

Regards!


    
 
 
Franc Buijsen
Franc Buijsen
03:27 Feb-18-2003
Re: How to detect cracks in dams
Assuming the dams are of steel. Cracks can be found underwater by means of eddy current or magnetic. Both techniques are intensively used on the North sea and in the harbours. There are a lot of companies in The Netherlands and the UK offering this service. We have trained divers to do this kind of work.


Franc


: On behalf of a reader I post this message:
: I am not sure if UT could work, but what about GPR or IRT?
: ------
: Dear Mr. Diedericks,
:
: We have divers that do maintenance and repair dams underwater. I was asked if there is an acoustical mean (ultrasound or else) that could be used underwater to detect cracks in dams as a preventive measure.
:
: Thank you for paying attention to my request.
:
: Regards!
.



    
 
 
Todd Allen
Consultant, Ground Penetrating Radar ( GPR )
Radarview Concrete and Underground 3D Imaging, USA, Joined Jan 2003, 7

Todd Allen

Consultant, Ground Penetrating Radar ( GPR )
Radarview Concrete and Underground 3D Imaging,
USA,
Joined Jan 2003
7
02:59 Feb-19-2003
Re: How to detect cracks in dams
If the Dam is concrete, GPR is great for thickness, and reinforcement location, but for cracks you need to use the Ultrasonic Impact-Echo method. If you need more information call me at 281-705-9476 (USA).

Thanks,
-Todd Allen

: On behalf of a reader I post this message:
: I am not sure if UT could work, but what about GPR or IRT?
: ------
: Dear Mr. Diedericks,
:
: We have divers that do maintenance and repair dams underwater. I was asked if there is an acoustical mean (ultrasound or else) that could be used underwater to detect cracks in dams as a preventive measure.
:
: Thank you for paying attention to my request.
:
: Regards!
.



    
 
 
Neil Gibson
Director
CNS Farnell Ltd, United Kingdom, Joined Jul 2003, 2

Neil Gibson

Director
CNS Farnell Ltd,
United Kingdom,
Joined Jul 2003
2
08:58 Feb-20-2003
Re: How to detect cracks in dams
: On behalf of a reader I post this message:
: I am not sure if UT could work, but what about GPR or IRT?
: ------
: Dear Mr. Diedericks,
:
: We have divers that do maintenance and repair dams underwater. I was asked if there is an acoustical mean (ultrasound or else) that could be used underwater to detect cracks in dams as a preventive measure.
:
: Thank you for paying attention to my request.
:
: Regards!
.

The ultrasonic pulse velocity technique is widely used to detect cracks in concrete structures (assuming your dam is concrete! CNS Farnell can supply instruments and transducers for this purpose. Transducers for use at depths much below 1-2m are not standard but can be made. You will need access to both sides of the dam to detect cracks and other defects.

Take a look at our website www.cnsfarnell.com or call me for more information on +44 (0)20 8238 6900



    
 
 
asif
asif
05:50 Dec-11-2003
Re: How to detect cracks in dams
i m student of msc civil engg. i have to deliver a presentation so plz post it to me
thanks
asif


    
 
 

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