TY - JOUR A1 - Algernon, Daniel A1 - Gräfe, Boris A1 - Mielentz, Frank A1 - Köhler, B. A1 - Schubert, F. T1 - Imaging of the Elastic Wave Propagation in Concrete Using Scanning Techniques: Application for Impact-Echo and Ultrasonic Echo Methods JF - Journal of nondestructive evaluation N2 - Acoustic NDT methods like ultrasonic echo and impact-echo are successfully used for NDT of concrete structures. This paper describes useful techniques for a detailed experimental study of the elastic wave propagation, which is highly relevant for the interpretation of the results obtained from practical measurement applications. By using a scanning laser vibrometer it becomes possible to obtain a 2D visualization of the elastic waves propagating along the surfaces of concrete specimens. Time slices are prepared so that the wave field becomes apparent. In order to visualize especially the surface wave propagation a similar technique using a scanning system with a piezoelectric sensor is applied. The results obtained provide an appropriate basis for the comparison with numerical results from 3-D Elastodynamic finite integration technique (EFIT) calculations, which is demonstrated here. Examples are presented for the application with phased array ultrasonic echo, air-coupled ultrasonic echo and impact-echo. KW - Ultrasonic-echo KW - Impact-echo KW - Laser vibrometer KW - Visualization of wave propagation KW - Elastodynamic finite integration technique (EFIT) PY - 2008 UR - http://www.springerlink.com/content/v739785102l6367x/fulltext.pdf DO - https://doi.org/10.1007/s10921-008-0034-4 SN - 0195-9298 SN - 1573-4862 VL - 27 IS - 1-3 SP - 83 EP - 97 PB - Plenum Press CY - New York, NY AN - OPUS4-18031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zoëga, Andreas A1 - Shokouhi, Parisa A1 - Wiggenhauser, Herbert ED - Nagesh R. Iyer, ED - K. Balaji Rao, ED - N. Gopalakrishnan, ED - Bharatkumar, B. H. ED - V. Kalyanaraman, T1 - Propagation time of elastic surface waves on concrete specimens under uniaxial loads JF - Journal of structural engineering KW - Propagation time KW - Surface-wave KW - Concrete KW - Uniaxial loading KW - Laser vibrometer KW - Stress-dependency KW - Direction-dependency PY - 2009 SN - 0970-0137 VL - 36 IS - 1 SP - 11 EP - 15 CY - Madras AN - OPUS4-19462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -