Among the existing methods of Non-destructive Concrete Tests, The ultrasonic inspection can be considered as one of the most promising and reliable methods for testing of concrete. The non-destructive test (NDT) of concrete by UPV Test is a recognised test for the evolution of the in-situ concrete. Ultrasonic inspection is useful in qualitative assessment as well as realistic evaluation more of homogeneity & integrity of RCC structure rather than strength.
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Learn the procedure for ultrasonic testing and get the idea about the factors that affect ultrasonic pulse velocity in concrete. Here are the advantages of ultrasonic inspection in the concrete structures.
Advantages of Ultrasonic Inspection in Concrete Structure:
Following are the advantages of ultrasonic inspection in the concrete structure.
01. Ultrasonic inspection is useful in the qualitative assessment of the strength of concrete.
02. It is used to check the gradation of the concrete at different locations of structural members and plotting the same.
03. It is used to determine any discontinuity in cross sections like cracks, cover concrete, delamination, etc.
How to Estimate the Depth of Cracks?
The ultrasonic inspection can measure the depth of cracks in concrete elements. In UPV test, one transducer is placed on one side of the crack to produce the stress waves (ultrasonic pulse). The other transducer is positioned on the opposite side to receive the stress wave and the arrival times (transmit time) of waves will be monitored. Based on the transmit travel time of the wave, depth of cracks can be measured by mathematical equation method or graphical method.
There are other techniques available to measure the depth of cracks, but the ultrasonic testing is very simple and easy to perform. The ultrasonic testing gives a rapid measurements of the cracking depth.
04. It is used to evaluate the depth of surface layer or thickness of the concrete components.
05. It is used to find the spots that have different properties than the surrounding materials.
06. It is used to obtain a total control of a concrete structure, using the concrete property variations with the time.
07. It makes possible the continuous evaluation of concrete conditions during the entire service life of the structure.
08. Results of ultrasonic inspection can be used for diagnosis, prognosis and quality control.
In short, the UPV test is used:
- To assess the uniformity in the concrete members.
- To detect the internal imperfections.
- To evaluate the depth of imperfections.
- To estimate the deformation and distresses.
- To assess the compressive strength.
- To track the characteristics variations of concrete.
It is essential that test results are carefully evaluated and interpreted by the expert, who understand the ultrasonic inspection. Nowadays device of ultrasonic inspection has high penetrating power. It also ensures very easy measurement even for the very deep concrete members, and it is also highly sensitive thereby giving accurate results.