Evaluation of Radar and Complementary Echo Methods for NDT of Concrete Elements

Maierhofer, Christiane; Zacher, G.; Kohl, Christoph; Wöstmann, Jens

doi:10.1007/s10921-008-0030-8

Cited by 28 publications

(16 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the double dependency on porosity and degree of saturation, the cause of the measurement variation in the NDT parameter cannot be easily determined. Consequently, a combination of complementary methods is recommended in order to accurately assess the degree of saturation and porosity of concrete [12, [26][27][28]. When relying on such a combination procedure, it becomes possible to evaluate durability indicators and/or mechanical properties, as reported by several authors.…”

Section: Introductionmentioning

confidence: 99%

Development of a calibration methodology to improve the on-site non-destructive evaluation of concrete durability indicators

Villain

Garnier²,

Sbartaï

et al. 2018

Mater Struct

View full text Add to dashboard Cite

Development of a calibration methodology to improve the on-site non-destructive evaluation of concrete durability indicators. Materials and Structures, Springer Verlag, 2018, 51 (2), phone: 33 (0)2 40 84 57 22, fax: 33 (0)2 40 84 59 97 (ORCID 0000-0002-4478-034X) ABSTRACTThis paper addresses the use of non-destructive testing (NDT) methods to assess indicators for both the concrete durability (porosity, degree of saturation) and mechanical properties (elasticity modulus, compressive strength) of reinforced concrete structures. NDT results, called "observables", are obtained by means of ultrasonic or electromagnetic methods and then correlated with these mechanical and durability indicators. The conversion model used to transform observables into indicators depends on the actual concrete mix design. If this conversion model is unavailable for the reinforced structure under study, then the evaluation may be inadequate due to Please cite the published version in Materials and Structures, 2018, https://doi.2 high uncertainty on the results. This paper proposes a calibration methodology to derive a conversion model appropriate for the structure by use of a minimum number of cores in order to improve the on-site evaluation. A motorway bridge is tested and characterized by NDT, after which some cores are extracted for calibration and others for validation. The cores are subsequently nondestructively characterized in the laboratory and/or used to determine indicators by means of standardized destructive methods. The non-destructive (ND) calibration protocol on cores is presented first. Next, NDT results recorded in situ and on the corresponding core are compared.Also, durability indicators deduced from on-site NDT measurements in addition to calibration are compared with reference durability indicators that have been independently determined by standard destructive methods. Results obtained by analyzing more than 1600 data fully validate the tested calibration methodology.

show abstract

Section: Introductionmentioning

confidence: 99%

Development of a calibration methodology to improve the on-site non-destructive evaluation of concrete durability indicators

Villain

Garnier²,

Sbartaï

et al. 2018

Mater Struct

View full text Add to dashboard Cite

show abstract

“…Kaftandjian et al (Kaftandjian, Min, Dupuis, & D., 2005) utilized a data fusion approach to improving weld inspection by NDTs, combining the use of evidence theory and fuzzy logic; in their framework, X-ray and ultrasonic inspection were modeled in order to generate 3D images from both NDTs, for evaluating defect detection and defect sizing of welded joints for industrial purposes, showing that the fusion of data significantly enhances the reliability of the defect detection. Maierhofer et al (Maierhofer, Zacher, Khol, & Wöstmann, 2008) used radar, ultrasonic, impact-echo and thermography data fusion for predicting deterioration of concrete vehicular bridges, it was established that the data fusion technique increases the reliability, and improved the accuracy of the quantitative results, exploiting the different and sometimes complementary physical effects provided by different NDTs. Lui et al (Liu, Forsyth, & Komorowski, 2007) provide a very wide state-of-the-art regarding NDTs data fusion techniques, they established that the usage of multiple NDTs methods is employed in order to increase the reliability and reduce the uncertainty of testing and evaluation.…”

Section: Introductionmentioning

confidence: 99%

Prediction of the Static Modulus of Elasticity Using Four non Destructive Testing

Chávez-García

Alonso-Guzmán

Martínez-Molina

et al. 2014

Revista de la Construcción

View full text Add to dashboard Cite

The static modulus of elasticity (Es) is an important parameter in the analysis of hydraulic concrete structures, changes have been made to the regulation of construction; these changes require minimum values for the Es, so now, in addition to concrete compressive strength (f´c) also Es values should be ensured. A methodology to predict Es is proposed, specifically, the Es were modeled by testing: ultrasonic pulse velocity (UPV), electrical resistivity test (ERT), resonance frequency test (RFT), the Hammer Test Rebound (HTR) and f´c. In order to generate models multiple linear regression technique was used. Cylindrical specimens were prepared in two stages, in the first stage was simulated laboratory conditions in the second stage was simulated conditions of concrete made in situ. All cylinders were subjected to non-destructive and destructive tests at different ages. The research objective is to predict Es from the results of destructive tests (traditionally employed to obtain Es) and nondestructive testing. It was possible to obtain a model whose correlation coefficient indicates the good approximation in the generated predictions. ResumenEl módulo estático de elasticidad (Es) es un parámetro importante en el análisis de las estructuras de concreto hidráulico, se han realizado cambios en la regulación de la construcción; estos cambios requieren valores mínimos de los Es, por lo que ahora, además de la resistencia a la compresión del concreto (f'c) también deben garantizarse valores de Es. Se propone una metodología para predecir Es, específicamente, los Es fueron modelados con las pruebas: velocidad de pulso ultrasónico (UPV), prueba de resistividad eléctrica (ERT), prueba de frecuencia de resonancia (RFT), prueba de rebote de martillo (HTR) y f'c. Se utilizó la técnica de regresión lineal múltiple para generar los modelos. Se elaboraron especímenes cilíndricos en dos etapas, la primera simulando condiciones de laboratorio y en la segunda simulando condiciones de concreto hecho en campo. Todos los cilindros se sometieron a pruebas no destructivas y destructivas a diferentes edades. El objetivo de la investigación es predecir Es con los resultados obtenidos de pruebas destructivas (empleadas tradicionalmente para obtener Es) y pruebas no destructivas. Fue posible obtener un modelo cuyo coeficiente de correlación indica la buena aproximación en las predicciones generadas.Palabras clave: Concreto hidráulico, Modulo de Elasticidad Estático, Modulo de Elasticidad Dinámico, Prueba no Destructivas, Resistencia a la compresión.

show abstract

“…The more commonly used methods are based on classification (like Dempster-Shafer theory) in particular for image fusion [3][4][5][6][7]. Data fusion is also already used for assessing civil engineering components [4][5]8].…”

Section: Data Fusion Processmentioning

confidence: 99%