Evaluation of retroreflective corner echo for detection of surface breaking cracks in concrete by ultrasound

• DOI: 10.58286/27256
• Publication Date: 2023-01-16T14:44:01Z
• Authors: Ute Rabe; ; Sergey Pudovikov; ; Herbert Wiggenhauser; ; Hans-Georg Herrmann; ; Prathik Prabhakara; ; Ernst Niederleith...
• Keywords: Echo (communications protocol); Reflection; SIGNAL (programming language); Ranging

The retroreflective corner echo is used, for example, in ultrasonic non-destructive testing of metals to find fatigue cracks tubes or shafts. If the much weaker crack tip signal additionally detected, length can also be determined. A reflection occurs cases surface breaking with predominantly perpendicular orientation surface. intensity depends on angle incidence and wave mode used. For reliable detection vertical metals, transversal waves are commonly which propagate at an 37° 53° inspection As shown this contribution, wide spread low frequency arrays dry point contact sources available concrete allow receive echoes. These devices generate structures a large divergence sound field. series experiments was carried out such specimens artificial test defects controlled induced different depths. time-of-flight signals were recorded, exported reconstructed utilising SAFT (Synthetic Aperture Focusing Technique) algorithm. reconstruction parameters adjusted visualize indication. will shown, targeted processing, reproducible possible. thus exploited civil engineering concrete.