Reinforcement Effect on the Ultrasonic Pulse Velocity in Concrete, Depending on the Sounding Method and Measuring Device
29th European Conference on Acoustic Emission Testing: CD Proceedings 2010
Uldis Lencis, Aigars Ūdris, Aleksandrs Korjakins

In practice it is often required to determine the technical condition and the load carrying capacity of reinforced concrete. The quality of the constructions is also characterized by the structural properties of the concrete. However, sometimes the obtaining of the full value concrete specimens from such structures is problematic to carry out further researches with the material destructive test methods. It is known that physical and mechanical properties of concrete are best characterized by the density, porosity and strength of the structure. The integrity of such properties can be assessed by using material nondestructive test method ― by applying the ultrasonic pulse velocity measuring devices. At the same time, it is also known that there are several factors that influence the ultrasonic pulse propagation velocity in the concrete and the reinforced concrete structures. The earlier performed investigations have established that presence of the reinforcement located close to the surface of the tested concrete increases the ultrasonic pulse velocity. Reinforcement effect is also described in the notes to various standards. In practice the concrete structures of many different building objects have been tested with specific ultrasonic devices, and obtained results leads to the doubts about the relevance of reinforcement effects. To explore this question, 5 model specimens were manufactured with different diameter of reinforcement rebars. Diameters of the rebars used for specimens ― 6; 8; 12; 16 and 22 mm. For reinforced concrete structures, which are necessary to test in a larger area, reinforcement diameter normally does not exceed the greater of the above mentioned size. Furthermore, determining of the rebars dislocation in large areas is very time-consuming process, even if for this purpose corresponding device has been used before ultrasonic velocity measurements. In present research performing measurements in the zones direct over the rebars and in the rebar-free zones (in plain concrete), different ultrasonic measuring devices show a comparatively different results. It is concluded that the reinforcement effect on the ultrasonic pulse velocity in concrete depends on both sounding methods and technical parameters of the measuring device.


Atslēgas vārdi
Concrete, nondestructive testing, ultrasonic pulse velocity, effect of reinforcement

Lencis, U., Ūdris, A., Korjakins, A. Reinforcement Effect on the Ultrasonic Pulse Velocity in Concrete, Depending on the Sounding Method and Measuring Device. No: 29th European Conference on Acoustic Emission Testing: CD Proceedings, Austrija, Vienna, 8.-10. septembris, 2010. Vienna: TÜV Austria, European Working Group on Acoustic Emission, NDT.net, 2010, 35.-42.lpp. ISBN 978-3-200-01956-0.

Publikācijas valoda
English (en)
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