Filtern
Erscheinungsjahr
Dokumenttyp
- Beitrag zu einem Sammelband (67) (entfernen)
Referierte Publikation
- nein (67)
Schlagworte
- Radar (21)
- Zerstörungsfreie Prüfung im Bauwesen (16)
- Non-destructive testing (12)
- Beton (10)
- Concrete (10)
- Masonry (10)
- Active thermography (7)
- Aktive Thermografie (7)
- Non-destructive testing in civil engineering (6)
- Impuls-Thermografie (5)
- Ultraschall (5)
- ZfPBau (5)
- Hohlstellen (4)
- Mauerwerk (4)
- Plaster (4)
- Thermography (4)
- Ultrasonic (4)
- Ultrasonics (4)
- Fehlstellen (3)
- Historic masonry (3)
- Historisches Mauerwerk (3)
- Kiesnester (3)
- Moisture (3)
- Puls-Phasen-Thermografie (3)
- Spaltklinker (3)
- Ablösungen (2)
- Case studies (2)
- Combination of methods (2)
- Crack sizing (2)
- Cultural heritage (2)
- Data fusion (2)
- Datenfusion (2)
- Fallstudien (2)
- Impact-Echo (2)
- Impulse thermography (2)
- Impulse-Thermografie (2)
- Laser excitation (2)
- Multispektralklassifizierung (2)
- Quality control (2)
- SAFT (2)
- Spannbetonbrücken (2)
- Stone (2)
- Strategies (2)
- Structural modelling (2)
- Structure (2)
- Voids (2)
- Acitve thermography (1)
- Akustische Verfahren (1)
- Altes Museum (1)
- Asphalt (1)
- Aufprallecho (1)
- Bauwerksoberflächen (1)
- Beton, Stabilität (1)
- Betondecke (1)
- Bewehrung (1)
- Bonding (1)
- Bonding problems (1)
- Brick (1)
- Brückenuntersuchung (1)
- CFK-Laminate (1)
- Camera calibration (1)
- Carbon fibre (1)
- Civil engineering (1)
- Concrete bridge (1)
- Concrete bridges (1)
- Crack mapping (1)
- Crack monitoring (1)
- Cultural Heritage (1)
- Damage (1)
- Data Fusion (1)
- Debonding (1)
- Defect shape reconstruction (1)
- Delamination (1)
- Denkmalpflege (1)
- Elektromagnetische Verfahren (1)
- Endoskopie (1)
- Europäische Kommission (1)
- FEM (1)
- FEM Modeling (1)
- FEM modeling (1)
- Fehlstelle (1)
- Feuchte (1)
- Feuchtigkeit (1)
- Finite differences (1)
- Finite element simulation (1)
- Flat Jack (1)
- Flood (1)
- Geoelektrik (1)
- Heating (1)
- Historic buildings (1)
- Historic structure (1)
- Historische Gebäude (1)
- Hohlraum (1)
- Hohlraumgehalt (1)
- IR-Aufnahme (1)
- Impact-echo (1)
- Impuls Radar (1)
- Impulse-Thermography (IR) (1)
- Infrared radiation (1)
- Inversion (1)
- Kulturgüter (1)
- Laboratory Testing (1)
- Laminates (1)
- Laser (1)
- Laserscanner (1)
- Lichtschnittverfahren (1)
- Local thermal excitation (1)
- Merkblätter (1)
- Microseismic (1)
- Minderdicken (1)
- Modellierung (1)
- Modelling (1)
- Monitoring (1)
- Multispektraler Laserscanner (1)
- Multispektraltechnik (1)
- NDT-CE (1)
- Neues Palais (1)
- Numerical SImulation (1)
- Oberflächeneigenschaften (1)
- Optische Verfahren (1)
- Ortung von Fehlstellen und Ablösungen (1)
- PPT (1)
- Parkett (1)
- Polarisation (1)
- Praktische Anwendungen (1)
- Probekörper (1)
- Prüfung (1)
- Puls-Phasen Thermografie (1)
- Pulse-phase-thermography (1)
- Pulsed thermography (1)
- Putz auf Beton und Mauerwerk (1)
- Putzablösung (1)
- Quality assurance (1)
- Quantitative Methode (1)
- Quantitative characterization (1)
- Radarverfahren (1)
- Rechteckimpuls-Erwärmung (1)
- Reinforcement (1)
- Reinforcement bars (1)
- Repair (1)
- Risse (1)
- Rückwand (1)
- SAR (1)
- Sandstone (1)
- Schadenserfassung (1)
- Schichtablösungen (1)
- Schichtdicken (1)
- Seismik (1)
- Sonics (1)
- Spannglieder (1)
- Stahlbeton (1)
- Statue (1)
- Strengthening (1)
- Supervision of CFRP-Strengthening (1)
- Temperature decay (1)
- Test specimen (1)
- Thermal contrast (1)
- Thermal transport (1)
- Thermische Welle (1)
- Thermografie (1)
- Tomography (1)
- Ultraschall Echo (1)
- Ultraschall-Rückstreuung (1)
- Ultraschallverfahren (1)
- Validation (1)
- Velocity calibration (1)
- Verfahrenskombination (1)
- Wanddicke (1)
- Water transport (1)
- Wood preservatives (1)
- Zerstörungsfreie Prüfung (1)
- Zerstörungsfreie Prüfung im Bauwesen (ZfPBau) (1)
- Zerstörungsfreie Untersuchung (1)
- ZfP-Bau-Verfahren (1)
The delamination of a plaster layer, which covers a concrete structure, can be detected by active thermography. In this paper, a systematic series of measurements is described, where the gap between plaster and concrete was varied. These investigations were compared to FEM-simulations. The experimental and simulated data were in good agreement. It was found that the used experimental setup yields only marginal differences between fixed and lose plaster in the thermal behavior. However, significant characteristics within the temperature decays could be resolved, which are clearly related to the air gap.
In this article, we present a measurement procedure to gain information about depth and angle of open surface cracks. The method is based on a local excitation with, e.g., a laser. The resulting surface temperature is recorded with an infrared camera. Based on this data, crack-caused anisotropies in the lateral heat flow can be detected and exploited to characterise the cracks.
The experimental set-up is based on a Nd:YAG laser. The beam is focused on the test sample by using an optical scanner to generate the required lateral heat flow. The time resolved temperature distribution is recorded with a high-speed infrared camera (InSb FPA, 3 to 5 µm) providing a frame rate of up to 500 Hz.
Up to now, only qualitative information was gained from measurements of this type. Whereas the local transient behaviour of temperature distribution provides also quantitative information of the crack parameters. The general concept of the method presented herein has already been published [1], but the mentioned publication is focused on the crack depth only.
In this paper, we can show that it is possible to simultaneously resolve the angle and depth and, in particular, the depth of non-perpendicular cracks.
Monitoring of cracks in historic concrete structures using optical, thermal and acoustical methods
(2015)
Cracks are a major issue in the field of cultural heritage. In order to evaluate the significance of a crack, a long term monitoring of the damaged region is required. However, there is a lack of easy to operate tools for such monitoring measures. Therefore, new or existing methods for other applications have to be optimised for cultural heritage investigation. The paper describes the application of such crack observation methods on a historic concrete sculpture. Beside conventional methods, like mapping by hand and ultrasonic depth profiling, a novel tracking system is presented. Furthermore, the suitability of active thermography for the investigation of cracks was investigated. The results show promising prospects for these non-destructive techniques.
The structural safety, durability and performance of the infrastructure is of primary interest in every country. An efficient system for early and regular structural assessment as well as for quality assurance during and after the construction of new structures and of reconstruction processes is urgently required. At BAM, NDT methods to be applied in civil engineering are developed and their application improved. From the experience of on-site assessments, quality assurance systems and methodologies for regular inspections are elaborated. This work is mainly performed in the frame of externally funded research projects.