We offer services for testing concrete, where the velocity of ultrasonic pulses is measured and identification of cracks, voids, strength, and elasticity are checked to determine the areas which can provide the basis for recognizing the defects. The pulse velocity in a material depends on its density and its elastic properties, which in turn are related to the quality and the compressive strength of the concrete.
In ultrasonic testing, very short ultrasonic pulse-waves with centre frequencies ranging from 0.1-15 MHz and occasionally up to 50 MHz are launched on the material to detect internal flaws or to characterize the material. The testing is done through methods such as ‘Reflection’ and ‘Attenuation’.
In reflection mode, the transducer performs both the sending and the receiving functions of the pulsed waves; as the “sound” is reflected back to the device. Reflected ultrasound comes from an interface, such as the back wall of the object or from an imperfection in the object. The diagnostic machine displays these results in the form of a signal with an amplitude representing the intensity of the reflection and the distance, representing the arrival time of the reflection.
In attenuation mode, a transmitter sends ultrasound through one surface, and a separate receiver detects the amount that has reached it on another surface after travelling through the medium. Imperfections or other conditions in the space between the transmitter and receiver reduce the amount of sound transmitted, thus revealing their presence. Using a couplant increases the efficiency of the process by reducing the losses in the ultrasonic wave energy due to separation between the surfaces.
Ultrasonic Testing has high penetrating power which enables detection of the deep flaws, determining the size, shape, orientation, and nature of the defects, in the area through its high sensitivity that allows testing of very small flaws. It has greater accuracy than other nondestructive methods in determining the depth of internal flaws and the thickness of parts with parallel surfaces.
The Ultrasonic Testing also provides path length measurement, surface velocity measurement and crack depth measurement.
The pulses are introduced to the concrete by a piezoelectric transducer and a similar transducer acts as a receiver to monitor the surface vibration caused by the arrival of the pulse.