The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform

Ivana Banjadpečur - One of the best experts on this subject based on the ideXlab platform.

  • Non-Destructive Testing of Polymer Modified Concrete
    Brittle Matrix Composites 8, 2007
    Co-Authors: Jure Galić, Ivana Banjadpečur
    Abstract:

    Addition of polymer to modify concrete (PMC) mixtures significantly changes its properties in fresh and hardened states. This is why the evaluation of results of non-Destructive tests is not directly applicable to PMC. As PMCs are currently used in various applications, it is necessary to investigate the possibility of applying the existing non-Destructive test methods developed for the evaluation of mechanical properties of ordinary concretes. These methods are quite simple and inexpensive, but data analysis and result interpretation require adequate experience. Direct determination of mechanical properties of concrete with non-Destructive Testing methods is one of the biggest tasks in modern civil engineering, and despite limitations significant improvements have been made in this area.In this paper the results of the study are presented in which twenty concrete mixtures with different cement amounts, w/c ranging from 0.35 to 0.65, different aggregate size and polymer amounts were tested. The relation between mechanical properties obtained by Destructive and non-Destructive Testing methods of the laboratory cast PMC specimens is determined. © 2006 Institute of Fundamental Technological Research, Warsaw. All rights reserved.

  • Non-Destructive Testing of Polymer Modified Concrete
    Brittle Matrix Composites, 2006
    Co-Authors: Jure Galić, Ivana Banjadpečur
    Abstract:

    Abstract Addition of polymer to modify concrete (PMC) mixtures significantly changes its properties in fresh and hardened states. This is why the evaluation of results of non-Destructive tests is not directly applicable to PMC. As PMCs are currently used in various applications, it is necessary to investigate the possibility of applying the existing non-Destructive test methods developed for the evaluation of mechanical properties of ordinary concretes. These methods are quite simple and inexpensive, but data analysis and result interpretation require adequate experience. Direct determination of mechanical properties of concrete with non-Destructive Testing methods is one of the biggest tasks in modern civil engineering, and despite limitations significant improvements have been made in this area. In this paper the results of the study are presented in which twenty concrete mixtures with different cement amounts, w/c ranging from 0.35 to 0.65, different aggregate size and polymer amounts were tested. The relation between mechanical properties obtained by Destructive and non-Destructive Testing methods of the laboratory cast PMC specimens is determined.

D. Wei - One of the best experts on this subject based on the ideXlab platform.

  • Progress of air-coupled ultrasonic non-Destructive Testing technology
    Jixie Gongcheng Xuebao Chinese Journal of Mechanical Engineering, 2008
    Co-Authors: Z. Zhou, D. Wei
    Abstract:

    Air-coupled ultrasonic non-Destructive Testing, possessing the characters of complete non-contact and non-destruction, can be used in some situations in which traditional ultrasonic Testing is hardly applicable. The development of air-coupled ultrasonic non-Destructive Testing is summarized, and the main technical difficulties that restrict its progress are analyzed. Two methods to improve the efficiency of air-coupled ultrasonic transducers and corresponding research works are presented. Main detecting methods and corresponding application fields of air-coupled ultrasonic Testing are introduced. It is concluded that air-coupled ultrasonic Testing technique will be applied more widely in the future, however, the high efficiency transducer is a prerequisite for the successful application of the technology, and is also a focus of present research in this technical field.

J Hewitt - One of the best experts on this subject based on the ideXlab platform.

  • rapid thermal non Destructive Testing of aircraft components
    Composites Part B-engineering, 2000
    Co-Authors: Declan G Bates, G F Smith, Dawei Lu, J Hewitt
    Abstract:

    This paper compares the use of different thermal non-Destructive Testing techniques to rapidly inspect carbon fibre composite aircraft components. Samples were prepared to simulate inclusions and barely visible impact damage in carbon fibre reinforced plastic laminate which represent faults in the manufacturing process and in-service environment respectively. The limits of material fault detection were then compared for transient and lock-in thermography and the results were verified with underwater ultrasonic c-scans. The paper concludes that lock-in thermography is a more powerful technique to detect impact damage and that transient thermography is more suitable for detecting inclusions. Thermal non-Destructive Testing is up to 30 times quicker than underwater ultrasonic c-scanning and may ultimately provide the solution to the problem of rapid quantitative in-service and manufacturing process inspection of commercial aircraft components.

Gerd Dobmann - One of the best experts on this subject based on the ideXlab platform.

  • non Destructive Testing methods
    2010
    Co-Authors: Christiane Maierhofer, Hanswolf Reinhardt, Gerd Dobmann
    Abstract:

    Part 1 Planning and implementing non-Destructive Testing of reinforced concrete structures: Planning a non-Destructive test programme for reinforced concrete structures Non-Destructive Testing methods for building diagnosis-state of the art and future trends Development of automated non-Destructive evaluation (NDE) systems for reinforced concrete structures and other applications Structural health monitoring systems for reinforced concrete structures Combining the results of different non-Destructive evaluation techniques for reinforced concrete: data fusion. Part 2 Individual non-Destructive Testing techniques: Wireless monitoring of reinforced concrete structures Non-Destructive Testing of concrete with electromagnetic and acoustic-elastic waves: data analysis Non-Destructive Testing of concrete with electromagnetic acoustic-and elastic waves: modelling and imaging Laser-induced breakdown spectroscopy (LIBS) for the evaluation of reinforced concrete structures Acoustic emission (AE) for the evaluation of reinforced concrete structures Magnetic flux leakage (MFL) for the non-Destructive evaluation of prestressed concrete structures Electrical resistivity for the evaluation of reinforced concrete structures Capacimetry for the evaluation of reinforced concrete structures Techniques for measuring the corrosion rate (polarization resistance) and the corrosion potential of reinforced concrete structures Ground penetrating radar for the evaluation of reinforced concrete structures Radar tomography for the evaluation of reinforced concrete structures Active thermography for the evaluation of reinforced concrete structures Nuclear magnetic resonance imaging (NMR) for the evaluation of reinforced concrete structures Stress wave propagation for evaluation of reinforced concrete structures Surface wave techniques for the evaluation of concrete structures Impact-echo techniques for the evaluation of concrete structures Ultrasonic techniques for the evaluation of reinforced concrete structures. Part 3 Case studies: Inspection of concrete retaining walls using ground penetrating radar (GPR): a case study Acoustic emission and impact-echo techniques for the evaluation of reinforced concrete structures: a case study Using ground penetrating radar to assess an eight-span post-tensioned viaduct: a case study.

  • Quantitative non-Destructive Testing: The integration of non-Destructive Testing and probabilistic fracture mechanics
    Advances in Construction Materials 2007, 2007
    Co-Authors: Jochen H. Kurz, Dragos Cioclov, Gerd Dobmann
    Abstract:

    Nowadays, the non-Destructive evaluation of structural components allows the detection of cracks and other types of flaws with a high resolution. When cracks are involved in mechanical failure events, fracture mechanics provides concepts for lifetime prediction of components when component geometry, material characteristics and load intensity under steady state or impact loading are known. Under fatigue loads additionally material laws have to be observed. Bringing together these disciplines, quantitative non-Destructive Testing for lifetime prediction is possible. Due to measurement uncertainties related to crack size geometry, material parameters' inherent scatter and load history are not unambiguously assessable. Therefore, statistical distributions are assumed (e. g. Normal or Weibull) and probabilistic fitness for service assessment (FFS) is performed rather than a deterministic one. This concept of combining quantitative non-Destructive Testing and probabilistic FFS assessment works well for metals. The fracture mechanics analysis under predominantly static loading has at its core the so called Failure Assessment Diagram (FAD). Hereby, an illustrative tool for condition monitoring is supplied which is also accepted in design rules and codes. Software which addresses the criticality of cracks and other flaw types in the shell of cylindrical pressure vessels was developed. The application of the concept of probabilistic fracture mechanics using Monte Carlo simulation is demonstrated for one example from pipelines.

  • Quantitative Non-Destructive Testing: The integration of non-Destructive Testing and probabilistic fracture mechanics
    Advances in Construction Materials 2007, 2007
    Co-Authors: Jochen H. Kurz, Dragos Cioclov, Gerd Dobmann
    Abstract:

    Nowadays, the non-Destructive evaluation of structural components allows the detection of cracks and other types of flaws with a high resolution. When cracks are involved in mechanical failure events, fracture mechanics provides concepts for lifetime prediction of components when component geometry, material characteristics and load intensity under steady state or impact loading are known. Under fatigue loads additionally material laws have to be observed. Bringing together these disciplines, quantitative non-Destructive Testing for lifetime prediction is possible.

Jure Galić - One of the best experts on this subject based on the ideXlab platform.

  • Non-Destructive Testing of Polymer Modified Concrete
    Brittle Matrix Composites 8, 2007
    Co-Authors: Jure Galić, Ivana Banjadpečur
    Abstract:

    Addition of polymer to modify concrete (PMC) mixtures significantly changes its properties in fresh and hardened states. This is why the evaluation of results of non-Destructive tests is not directly applicable to PMC. As PMCs are currently used in various applications, it is necessary to investigate the possibility of applying the existing non-Destructive test methods developed for the evaluation of mechanical properties of ordinary concretes. These methods are quite simple and inexpensive, but data analysis and result interpretation require adequate experience. Direct determination of mechanical properties of concrete with non-Destructive Testing methods is one of the biggest tasks in modern civil engineering, and despite limitations significant improvements have been made in this area.In this paper the results of the study are presented in which twenty concrete mixtures with different cement amounts, w/c ranging from 0.35 to 0.65, different aggregate size and polymer amounts were tested. The relation between mechanical properties obtained by Destructive and non-Destructive Testing methods of the laboratory cast PMC specimens is determined. © 2006 Institute of Fundamental Technological Research, Warsaw. All rights reserved.

  • Non-Destructive Testing of Polymer Modified Concrete
    Brittle Matrix Composites, 2006
    Co-Authors: Jure Galić, Ivana Banjadpečur
    Abstract:

    Abstract Addition of polymer to modify concrete (PMC) mixtures significantly changes its properties in fresh and hardened states. This is why the evaluation of results of non-Destructive tests is not directly applicable to PMC. As PMCs are currently used in various applications, it is necessary to investigate the possibility of applying the existing non-Destructive test methods developed for the evaluation of mechanical properties of ordinary concretes. These methods are quite simple and inexpensive, but data analysis and result interpretation require adequate experience. Direct determination of mechanical properties of concrete with non-Destructive Testing methods is one of the biggest tasks in modern civil engineering, and despite limitations significant improvements have been made in this area. In this paper the results of the study are presented in which twenty concrete mixtures with different cement amounts, w/c ranging from 0.35 to 0.65, different aggregate size and polymer amounts were tested. The relation between mechanical properties obtained by Destructive and non-Destructive Testing methods of the laboratory cast PMC specimens is determined.