Ultrasonic tomography of metal structures using the digitally focused antenna array method

Methodology for Non-Destructive Identification of Thickness of Unilaterally Accessible Concrete Elements by Means of State-of-the-Art Acoustic Techniques

“…The identification of the thickness of concrete elements, especially the unilaterally accessible ones, has been the subject of studies by Bishko et al (2008), Kozlov et al (1997), Samokrutov et al (2002, and Samokrutov and Shevaldykin (2011). The researchers proposed to determine the thickness of such elements, using the ultrasonic echo technique.…”

“…The ultrasonic tomography and impact-echo techniques are suitable for this purpose (Gorzelańczyk et al 2012a, b;Gorzelańczyk, Schabowicz 2012;Hoła et al 2008Hoła et al , 2011Hoła, Schabowicz 2010;Schabowicz, Hoła 2012). Although these acoustic techniques (Hoła, Schabowicz 2010;Gorzelańczyk 2011Gorzelańczyk , 2012Goszczyńska et al 2012;Hoła, Schabowicz 2010;Stawiski 2012) have been described by Samokrutov and Shevaldykin (2011), Shevaldykin et al (2003) and Sansalone and Strett (1997) and in reports (ACI 228.2R-98 1998;Bundesanstalt für Straßenwesen 2001;ASTM C1383-04 2010, no methodology for their comprehensive (in the sense that the results of tests carried out using one of the techniques are subsequently verified by the results obtained by the other technique) use has been developed. The comprehensive approach is necessary especially when it is impossible to verify the test results in a destructive way.…”

Methodology of Nondestructive Identification of Defective Concrete Zones in Unilaterally Accessible Massive Members

“…The identification of defects, including excessively porous zones, in unilaterally accessible concrete members by means of ultrasonic tomography, has been studied, among others by Bishko et al (2008), Kozlov et al (1997), Samokrutov et al (2002Samokrutov et al ( , 2006, Samokrutov, Shevaldykin (2011) and Shevaldykin et al (2003). Also in Bishko (2007) the nondestructive ultrasonic tomography method was recommended for identifying defects in concrete members.…”

The development and current state of methods for the nondestructive testing and acoustic tomography of concrete

“…In particular, one of the most common transmitting receiving schemes that is used in the original SAFT method is pairwise generation and reception by all transducers. For acceleration of practical data processing in this scheme most often only a single generating element is used at a time, while all of the elements (including the generator) receive the signal [115]. If the condition of non corre latedness is required, this is achieved by selecting the distance (step) between the elements of the array; then, the oscillations that are received by the element that transmits the sounding pulse into the object could be weakly or entirely not correlated with the oscillations that are received at the same moment by a neighboring element of the array, so that the signals can also be used in accumulating the data.…”

“…In this case, the path of the antenna movement should be selected so that the different positions of the array overlap and the accumulation of echo signals from most points inside the object occurs along with the summing of even more received oscillatory scans from the same defects. Strictly speaking, the SAFT technique, which uses only the detected amplitude of the received signals for imaging of the internal structure of the object, is not fully tomographic, although the method is based on the principles of ray tomography [56,[114][115][116][117][118][119][120], in which the vector nature of acoustic fields in solids is usually omitted.…”