Non-destructive testing in civil engineering:

<p>The reassessment of bridges is becoming increasingly important. The basic requirement for analyses of structural safety is reliable knowledge about individual structures. This paper introduces the new approach to evaluate the quality of measured data gained from non-destructive testing (NDT) to provide reliable, objective, and relevant information about existing bridges. The purpose is to relate this validated knowledge to probabilistic analyses. Bridging the gap between NDT and numerical reassessments indicates reduced numerical uncertainties and residual service time extensions. This paper deals with an application of this approach using measurement data collected by ultrasonic technique at a prestressed concrete bridge.</p>

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Reliability assessment of existing bridge constructions based on results of non-destructive testing

MATEC Web of Conferences ◽

10.1051/matecconf/201819906001 ◽

2018 ◽

Vol 199 ◽

pp. 06001 ◽

Cited By ~ 1

Author(s):

Stefan Küttenbaum ◽

Alexander Taffe ◽

Thomas Braml ◽

Stefan Maack

Keyword(s):

Measurement Data ◽

Basic Research ◽

Relevant Information ◽

Structural Safety ◽

Non Destructive Testing ◽

Testing Methods ◽

Destructive Testing ◽

Uncertainty In Measurement ◽

Existing Structures ◽

Non Destructive

The non-destructive testing methods available for civil engineering (NDT-CE) enable the measurements of quantitative parameters, which realistically describe the characteristics of existing buildings. In the past, methods for quality evaluation and concepts for validation expanded into NDT-CE to improve the objectivity of measured data. Thereby, a metrological foundation was developed to collect statistically sound and structurally relevant information about the inner construction of structures without destructive interventions. More recently, the demand for recalculations of structural safety was identified. This paper summarizes a basic research study on structural analyses of bridges in combination with NDT. The aim is to use measurement data of nondestructive testing methods as stochastic quantities in static calculations. Therefore, a methodical interface between the guide to the expression of uncertainty in measurement and probabilistic approximation procedures (e.g. FORM) has been proven to be suitable. The motivation is to relate the scientific approach of the structural analysis with real information coming from existing structures and not with those found in the literature. A case study about the probabilistic bending proof of a reinforced concrete bridge with statistically verified data from ultrasonic measurements shows that the measuring results fulfil the requirements concerning precision, trueness, objectivity and reliability.

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Detection of near-surface reinforcement in concrete components with ultrasound

MATEC Web of Conferences ◽

10.1051/matecconf/201819906007 ◽

2018 ◽

Vol 199 ◽

pp. 06007

Author(s):

Sarah Vonk ◽

Alexander Taffe

Keyword(s):

Prestressed Concrete ◽

Concrete Cover ◽

Non Destructive Testing ◽

Destructive Testing ◽

Near Surface ◽

Measuring Devices ◽

Inductive Methods ◽

Surface Reinforcement ◽

The University ◽

Non Destructive

Ultrasonic testing of concrete has grown in importance considerably in recent years in non-destructive testing in civil engineering (NDT-CE). In the past, the main focus was on the imaging of the internal construction of steel and prestressed concrete components. On the other hand, comparatively little attention was paid to the location of near-surface reinforcement and concrete cover measurement. In this research, it is shown to what extent ultrasound is suitable for the detection of near-surface reinforcement in addition to magnetic inductive methods. The measurements were carried out with the newly developed Pundit 250 Array from the company Proceq and with the measuring devices of the company Acsys, the A1220 Monolith and the A1040 Mira. The ultrasound data was analysed with the vendor-independent software InterSAFT of the University of Kassel. Systematic investigations were carried out on test specimens with a variety on the concrete cover, the diameter of the reinforcement and the reinforcement ratio in the form of mesh reinforcement close to the surface. The detectability and accuracy of the concrete cover were set in relation to the concrete cover, wavelength and reinforcement diameter, with the result that more detailed rules for the detection of reinforcement are formulated for the user, instead of the known λ/2-criterion.

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Piezoelectric Impedance-Based Non-Destructive Testing Method for Possible Identification of Composite Debonding Depth

Micromachines ◽

10.3390/mi10090621 ◽

2019 ◽

Vol 10 (9) ◽

pp. 621 ◽

Cited By ~ 4

Author(s):

Wongi S. Na ◽

Jongdae Baek

Keyword(s):

Composite Materials ◽

Composite Structures ◽

Structural Integrity ◽

Structural Safety ◽

Non Destructive Testing ◽

Destructive Testing ◽

Electromechanical Impedance ◽

Testing Method ◽

Piezoelectric Impedance ◽

Non Destructive

Detecting the depth and size of debonding in composite structures is essential for assessing structural safety as it can weaken the structure possibly leading to a failure. As composite materials are used in various fields up to date including aircrafts and bridges, inspections are carried out to maintain structural integrity. Although many inspection methods exist for detection damage of composites, most of the techniques require trained experts or a large equipment that can be time consuming. In this study, the possibility of using the piezoelectric material-based non-destructive method known as the electromechanical impedance (EMI) technique is used to identify the depth of debonding damage of glass epoxy laminates. Laminates with various thicknesses were prepared and tested to seek for the possibility of using the EMI technique for identifying the depth of debonding. Results show promising outcome for bringing the EMI technique a step closer for commercialization.

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A Study on the Detection of Internal Defect Types for Duct Depth of Prestressed Concrete Structures Using Electromagnetic and Elastic Waves

Materials ◽

10.3390/ma14143931 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3931

Author(s):

Young-Geun Yoon ◽

Jae-Yun Lee ◽

Hajin Choi ◽

Tae-Keun Oh

Keyword(s):

Prestressed Concrete ◽

Elastic Waves ◽

Principal Component ◽

Non Destructive Testing ◽

Destructive Testing ◽

Flexural Mode ◽

Impact Echo ◽

Multichannel Analysis ◽

Non Destructive

Prestressed concrete (PSC) is widely used for the construction of bridges. The collapse of several bridges with PSC has been reported, and insufficient grout and tendon corrosion were found inside the ducts of these bridges. Therefore, non-destructive testing (NDT) technology is important for identifying defects inside ducts in PSC structures. Electromagnetic (EM) waves have limited detection of internal defects in ducts due to strong reflections from the surface of the steel ducts. Spectral analysis of the existing impact echo (IE) method is limited to specific conditions. Moreover, the flexural mode in upper defects of ducts located at a shallow depth and delamination defects inside ducts are not considered. In this study, the applicability of the elastic wave of IE was analyzed, and multichannel analysis of surface, EM, and shear waves was employed to evaluate six types of PSC structures. A procedure using EM waves, IE, and principal component analysis (PCA) was proposed for a more accurate classification of defect types inside ducts. The proposed procedure was effective in classifying upper, internal, and delamination defects of ducts under 100 mm in thickness, and it could be utilized up to 200 mm in the case of duct defect limitations.

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Reconstruction of Barely Visible Impact Damage in Composite Structures Based on Non-Destructive Evaluation Results

Sensors ◽

10.3390/s19214629 ◽

2019 ◽

Vol 19 (21) ◽

pp. 4629 ◽

Cited By ~ 5

Author(s):

Wronkowicz-Katunin ◽

Katunin ◽

Dragan

Keyword(s):

Composite Structures ◽

Impact Damage ◽

Failure Mechanisms ◽

Structural Safety ◽

Non Destructive Testing ◽

Destructive Testing ◽

X Ray ◽

Computed Tomographic ◽

X Ray Computed ◽

Non Destructive

The occurrence of barely visible impact damage (BVID) in aircraft composite components and structures being in operation is a serious problem, which threatens structural safety of an aircraft, and should be timely detected and, if necessary, repaired according to the obligatory regulations of currently applied maintenance methodologies. Due to difficulties with a proper detection of such a type of damage even with non-destructive testing (NDT) methods as well as manual evaluation of the testing results, supporting algorithms for post-processing of these results seem to be of a high interest for aircraft maintenance community. In the following study, the authors proposed new approaches for BVID reconstruction based on results of ultrasonic and X-ray computed tomographic testing using authored advanced image processing algorithms. The studies were performed on real composite structures taking into consideration failure mechanisms occurring during impact damaging. The developed algorithms allow extracting relevant diagnostic information both from ultrasonic B-and C-Scans as well as from tomographic 3D arrays used for the validation of ultrasonic reconstructed damage locations, which allows for a significant improvement of the detectability of BVID in tested structures. The developed approach can be especially useful for NDT operators evaluating the results of structural NDT inspections.

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Automatisierung in der industriellen Endoskopie/Development of new means regarding sensor positioning and measurement data evaluation – Automation of Industrial Endoscopy

wt Werkstattstechnik online ◽

10.37544/1436-4980-2021-09-70 ◽

2021 ◽

Vol 111 (09) ◽

pp. 644-649

Author(s):

Lukas Bath ◽

Ole Schmedemann ◽

Thorsten Schüppstuhl

Keyword(s):

Deep Learning ◽

Measurement Data ◽

Circular Path ◽

Non Destructive Testing ◽

Destructive Testing ◽

Complex Evaluation ◽

Continuum Robot ◽

Recording Conditions ◽

Non Destructive ◽

Probe Head

Die speziell zur Inspektion von Kavitäten eingesetzte industrielle Endoskopie ist im Gegensatz zu anderen zerstörungsfreien Prüfverfahren bisher wenig automatisiert. Dies liegt größtenteils an der anspruchsvollen Handhabung der Geräte innerhalb schwer zugänglicher Bereiche sowie der komplexen Auswertung der aufgenommen Messdaten aufgrund hochvarianter Aufnahmebedingungen. In diesem Beitrag wird ein neuartiger Kontinuumsroboter vorgestellt, der die kontaktfreie Führung des Sondenkopfs auf einer Kreisbahn erlaubt und so reproduzierbarere und bessere Sichtbedingungen schafft. Zusätzlich wird ein Konzept zur automatisierten Messdatenauswertung basierend auf Deep Learning vorgestellt.   In contrast to other non-destructive testing methods, industrial endoscopy, which is used specifically for inspecting cavities, has so far been little automated. This is largely due to the demanding handling of the devices within areas that are difficult to access as well as the complex evaluation of the recorded measurement data due to highly variant recording conditions. In this paper, a novel continuum robot is presented that enables non-contact guidance of the probe head on a circular path, creating more reproducible and improved viewing conditions. Additionally, a concept for automated measurement data analysis based on Deep Learning is presented.

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Detecting the Defects in Concrete Components with Impact-Echo Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.577.1114 ◽

2014 ◽

Vol 577 ◽

pp. 1114-1118 ◽

Cited By ~ 2

Author(s):

Jing Liu ◽

Jun Xie ◽

Xiao Yu He ◽

Yu Shan He ◽

Jia Hui Zhong

Keyword(s):

Prestressed Concrete ◽

Large Scale ◽

Concrete Block ◽

Non Destructive Testing ◽

Destructive Testing ◽

Impact Echo ◽

The Impact ◽

Non Destructive ◽

Impact Echo Method

With the large-scale application of the prestressed concrete structure, the quality of the concrete component defects and pipeline grouting has increasingly become the focus of attention. The impact-echo scanner uses the nature of wave, which pass though different media at different velocities, to distinguish internal defects of concrete, pipe filling density and so on. In this paper, using the impact-echo method to detect the concrete block with prefabricated defects of shape, location, and size explores the effect of defect properties, parameter settings and detection environment to impact-echo preliminarily and also explores the relationship of pipeline filling status and impact-echo image. Based on this study, the article raised the problem met during this non-destructive testing methods applied to engineering, and accumulated a certain amount of available engineering data. The experiment results show that using the impact-echo method to identify the defects of concrete components and to test the quality of pipeline grouting is a more convenient and effective non-destructive testing method. Especially, with the radar method in the pipeline grouting quality inspection which complement each other to make up for the shortcomings the lightning wave in case of the metal medium total reflection phenomenon, cannot detect metal pipe grouting plumpness.

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