Time reverse modeling of acoustic emissions in a reinforced concrete beam

Georg Karl Kocur; Erik H Saenger; Christian U Grosse; Thomas Vogel

doi:10.1016/j.ultras.2015.10.014

Time reverse modeling of acoustic emissions in a reinforced concrete beam

Ultrasonics. 2016 Feb:65:96-104. doi: 10.1016/j.ultras.2015.10.014. Epub 2015 Oct 19.

Authors

Georg Karl Kocur¹, Erik H Saenger², Christian U Grosse³, Thomas Vogel⁴

Affiliations

¹ Institute of Structural Engineering, ETH Zurich, Stefano-Franscini-Platz 5, 8093 Zurich, Switzerland; Research-Development-Engineering, Halfen GmbH, Liebigstrasse 14, 40746 Langenfeld, Germany. Electronic address: georg.kocur@halfen.de.
² International Geothermal Centre Bochum, Lennershofstrasse 140, 44801 Bochum, Germany. Electronic address: erik.saenger@hs-bochum.de.
³ Center for Building Materials, Chair of Non-destructive Testing, Technical University Munich, Baumbachstrasse 7, 81245 Munich, Germany. Electronic address: grosse@cbm.bv.tum.de.
⁴ Institute of Structural Engineering, ETH Zurich, Stefano-Franscini-Platz 5, 8093 Zurich, Switzerland. Electronic address: vogel@ibk.baug.ethz.ch.

PMID: 26518525
DOI: 10.1016/j.ultras.2015.10.014

Abstract

The time reverse modeling (TRM) is applied for signal-based acoustic emission (AE) analysis of reinforced concrete (RC) specimens. TRM uses signals obtained from physical experiments as input. The signals are re-emitted numerically into a structure in a time-reversed manner, where the wavefronts interfere and appear as dominant concentrations of energy at the origin of the AE. The experimental and numerical results presented for selected AE signals confirm that TRM is capable of localizing AE activity in RC caused by concrete cracking. The accuracy of the TRM results is corroborated by three-dimensional crack distributions obtained from X-ray computed tomography images.

Keywords: Acoustic emission; Concrete; Elastic waves; Time reversal; Wave propagation.