TY - JOUR A1 - Grothe, Sven T1 - Ultrasonic signal evaluation used to detect temperature changes in a concrete specimen caused by a heating system JF - The e-journal of nondestructive testing & ultrasonics N2 - Ultrasonic measurement evaluation methods have been proven to be effective for detection of subtle changes, caused by temperature, load or moisture. To detect and localize temperature changes, a concrete block of 4 × 5 × 0.8 m3, including a heating cartridge and multiple temperature sensors, has been set up to change the temperature and monitor the temperature distribution in a certain area inside the specimen. An ultrasonic monitoring system with 40 ultrasonic sensors (20 transmitters, 20 receivers, 25 kHz central frequency) has been implemented on the specimen. Data from 400 sensor combinations was collected over the whole period of the experiment in an interval of 30 minutes. Quantitative methods (CodaWave Interferometry and Time of Flight method) were used to evaluate the changes in ultrasonic travel-time caused by the heating period, when the cartridge was active, and the cooling period after turning off the cartridge. Furthermore the travel-time changes from all 400 sensor combinations were used to locate the heating cartridge. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-346387 UR - http://www.ndt.net/?id=18336 SN - 1435-4934 VL - 20 IS - 11 SP - 1 EP - 4 PB - NDT.net CY - Kirchwald AN - OPUS4-34638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -