Advanced Integration and 3-D Visualization of Data from Multiple Nondestructive Evaluation Technologies

RESEARCH AND DEVELOPMENT OF GALVANIC ELECTROCHEMICAL SENSORS FOR MONITORING THE CORROSION STATE OF STEEL REBAR IN AGGRESSIVE ENVIRONMENTS CONTAINING CHLORIDE IONSThis paper presents the results of a study on the corrosion of steel reinforcement in concrete pore solutions contaminated with chloride ions. With increasing chloride concentration, the open-circuit potential and the anodic polarization curve shift towards more negative potential values, the passive potential region of the anodic polarization curve decreases. The corrosion rate of reinforcement was evaluated according to the linear polarisation resistance technique. Accordingly, the corrosion rate of steel reinforcement is 4.53 µA/cm2 in the solution containing 1 M Cl-. In this study, galvanic electrochemical sensors with low carbon steel anodes and copper cathodes were developed. In an environment with no or low Cl- concentration, where the reinforcement is passivated, the corrosion current density of the sensor does not exceed 10.0 µA/cm2. The corrosion current of the sensor increases sharply under cathodic control with increasing chloride content. Thus, the developed sensor has a high sensitivity to chloride corrosion and is capable of detecting pitting corrosion caused by chlorides at an early stage.

Application of nondestructive evaluation (NDE) technologies throughout cold chain logistics of seafood: Classification, innovations and research trends

A method is developed for presentation of a concrete bridge deck condition assessed by multiple nondestructive evaluation (NDE) technologies using a three-dimensional (3D) visualization pro...

Static and dynamic response of reinforced concrete (RC) bridge elements depends on the material characteristics and possibly introduced damage. While initial material variability can be introduced during construction, the dominant changes are a result of deterioration processes in RC elements. The most commonly found problem in bridge decks is corrosion induced concrete deterioration, which is initiated by rebar corrosion and afterwards extends into concrete cracking, delamination and ultimately concrete spalling. The effects of deterioration can be effectively detected and characterized using several complementary nondestructive evaluation (NDE) technologies. The presented approach relies on the use of five NDE technologies namely: impact echo, ultrasonic surface waves, ground penetrating radar, half-cell potential and electrical resistivity. The application of listed technologies is illustrated on material characterization and defect/deterioration detection of RC bridge decks. Incorporation of the NDE results in an enhanced structural identification analysis is illustrated.

Reinforced concrete bridge decks are exposed to several types of deterioration processes: corrosion, alkali–silica reaction, carbonation, shrinkage, freeze–thaw actions, and so forth. The most commonly found problem is corrosion-induced bridge deck delamination. Previous studies have shown that surveys of bridges relying on a single nondestructive evaluation (NDE) technology provide limited information about the condition of concrete bridge decks. To overcome limitations of individual technologies, a complementary approach using several NDE technologies should be used in bridge deck evaluation. The presented approach utilizes a suite of NDE technologies, namely, impact echo (IE), ultrasonic surface waves (USW), ground-penetrating radar (GPR), half-cell potential (HCP), and electrical resistivity (ER). The suite of NDE technologies was implemented in the evaluation of bridge decks on nine bridges in Iowa. The NDE was complemented by ground-truth measurements on the cores extracted from all nine bridge decks. Condition assessment with the five NDE technologies has clearly shown their advantages and limitations. For example, the GPR surveys provided assessment of concrete deterioration at relatively high speeds of data collection. In contrast, IE provided high accuracy in detection and characterization of delaminations in the deck but at a lower testing speed. HCP and ER tests provided assessment of the likelihood of corrosion, whereas the USW test provided accurate assessment of the effects of deterioration processes and defects on mechanical properties, primarily the degradation of the elastic modulus. Most important, the survey showed the advantages of use of multimodal NDE surveys in the comprehensiveness of condition assessment of concrete bridge decks.

As the requirements on the accuracy of nondestructive testing and evaluation are increasing, multiple nondestructive evaluation (NDE) methods are often employed to increase the reliability and reduce the uncertainty of the testing and evaluation. The need to process and analyze data from multiple sources uses the technique named data fusion, which has been growing rapidly in the NDE community in recent years. This paper reviews the progress in NDE data fusion techniques and examines the mathematical fusion algorithms, which include but are not limited to optimization methods, multiresolution approaches, heuristic methods, probabilistic methods, and scientific visualization. In the light of recent applications in NDE data fusion, important issues in handling the acquired data and applying the fusion algorithms are identified and discussed. A generic framework to apply the NDE data fusion process is described. The study on fusion of advanced NDE and sensor techniques opens up prospects for the diagnostic and prognostic health monitoring applications in the future.

Building condition assessment (BCA) is one of the important approaches in total asset management during the asset life cycle. BCA is to monitor the functional status of the asset during the asset use and maintenance phase in the asset life cycle. With regards to this, various non-destructive evaluation (NDE) technologies are adopted for building structure physical condition assessment from time to time to prevent any catastrophic incident to occur. Two case studies on inspection of internal structure condition of concrete wall and slab using image-based NDE were presented in this study. A well-known NDE technology, namely ground penetrating radar (GPR) was used to scan the concrete wall and slab to identify the internal structure condition of the concrete wall and slab. The GPR radargram obtained by the shorter wavelength radar signal is evaluated to resolve the internal structure and the defect in detail. Results of this study prove that GPR can detect the internal structure of the concrete wall and locate the moisture in the concrete slab due to poor waterproof design. With such convincing results, the application of GPR has set a new benchmark in BCA for building physical condition assessment; a crucial aspect for better building maintenance and management in total asset management.

Fusing collected inspection data provides comprehensive and relatively more accurate diagnostics of defects and accordingly more accurate condition assessment of structures. This paper presents a new two-tier method that utilized data fusion methods for condition assessment of reinforced concrete bridge decks. The method utilizes pixel and feature levels fusion of data collected from multiple nondestructive evaluation (NDE) methods such as ground penetrating radar, impact echo, half-cell potential, and electrical resistivity. Data and measurements of NDE methods are extracted from the Iowa Highway research board project 2011 report for three case studies. It is observed from the three cases that each level of data fusion has its unique advantage. The power of pixel level fusion lies in its ability to provide an overview of bridge deck deterioration in one map as it appears in the fused image. On the other hand, feature fusion works better when only specific types of defects such as corrosion, delamination, and deterioration captured from inspection carried out by each of technologies referred to above. The proposed method is tested against filed inspection methods and core sample results described in the three case studies. The main findings of this research recommend utilizing data fusion in two levels as a new method to facilitate and enhance the confidence and capabilities of inspectors in interpretation of the NDE test results.

For safe operation of high-consequence structures such as airplanes, ships, trains, chemical plants, electricity-generating units, nuclear reactors, oil and gas pipelines, and pressure vessels, periodic inspection using nondestructive evaluation (NDE) technology and a deterministic approach to modeling fatigue crack growth has been mandated by government in the energy and transportation sectors of the nation’s economy since the 1970s. Recent advances in web-based computing, direct measurement-based NDE, and a stochastic approach to remaining fatigue life cycle prediction model have made it possible to not only enhance the credibility of fatigue life prediction but also shorten the turn-around time between field-based NDE and office-based modeling, analysis, verification and integrity assessment back to the field for decision making. To illustrate this new concept in preventing structural failure and extending useful life of high-consequence systems, we first recount a lesson learned in the history of the deployment of the U.S. nuclear submarine fleet, where the emphasis was on the continuous monitoring of 100% of pipe and vessel welds from their initial placement to the discovery of tangible signs of fatigue damage way before the onset of service disruption. Using two crack length vs. fatigue life cycle plots, one being based on the deterministic and the other a stochastic model, we summarize the contrast between the two models in their ability to deliver a credible prediction of the remaining fatigue life cycle based on a periodic or continuous inspection mode. In conjunction with that summary, we answer an important question in designing an NDE-based inspection strategy, namely, whether the inspection should be periodic or continuous. We show in this paper that the key to the success of a continuous monitoring system for aging structure is an NDE capability in measuring not only the initial crack length and the initial crack growth rate, but also their standard deviations. We conclude with a remark that a continuous direct-measurement-based NDE inspection system, when coupled with a finite element modeling and analysis capability, is capable of monitoring not only surface but also subsurface cracks.

A review of research needs in nondestructive evaluation for quality verification in electric vehicle lithium-ion battery cell manufacturing

Considerations on reproducibility of potential and corrosion rate measurements in reinforced concrete

Data-driven visual model development and 3D visual analytics framework for underground mining

Acoustic tomography is an established nondestructive evaluation (NDE) technology that can be used to image the interior of large grained building materials such as concrete or masonry. A literature search focusing on geotomography and tomographic applications in infrastructure NDE was performed. This paper highlights some historical publications of interest as well as illustrates the general theory of acoustic tomography. A questionnaire was sent to the transportation departments of the 50 states. The questionnaire is general in scope, written to ascertain which NDE methods the states are using, and to identify their concerns and interests. The questionnaire asks the state officials whether the tomography technique seemed useful. The results of this question are presented in this paper. A data acquisition and processing system has been developed to facilitate an acoustic tomography system. Using an array of transducers and data processing software, the system is fast enough to internally image concrete structures in the field. Laboratory results and field applications are presented in the form of three case studies. The technique is shown to be useful for imaging of cracks, cold joints, and voids in concrete structures.

The opportunities for 3D visualisations are huge. People can be immersed inside their data, interface with it in natural ways, and see it in ways that are not possible on a traditional desktop screen. Indeed, 3D visualisations, especially those that are immersed inside head-mounted displays are becoming popular. Much of this growth is driven by the availability, popularity and falling cost of head-mounted displays and other immersive technologies. However, there are also challenges. For example, data visualisation objects can be obscured, important facets missed (perhaps behind the viewer), and the interfaces may be unfamiliar. Some of these challenges are not unique to 3D immersive technologies. Indeed, developers of traditional 2D exploratory visualisation tools would use alternative views, across a multiple coordinated view (MCV) system. Coordinated view interfaces help users explore the richness of the data. For instance, an alphabetical list of people in one view shows everyone in the database, while a map view depicts where they live. Each view provides a different task or purpose. While it is possible to translate some desktop interface techniques into the 3D immersive world, it is not always clear what equivalences would be. In this paper, using several case studies, we discuss the challenges and opportunities for using multiple views in immersive visualisation. Our aim is to provide a set of concepts that will enable developers to perform critical thinking, creative thinking and push the boundaries of what is possible with 3D and immersive visualisation. In summary developers should consider how to integrate many views, techniques and presentation styles, and one view is not enough when using 3D and immersive visualisations.

Majority of acoustic instruments widely used in industry and technology for non-destructive evaluation (NDE) make use of a linear elastic response of materials. The nonlinear approach to ultrasonic NDE is concerned with nonlinear material response, which is inherently related to the frequency changes of the input signal, and is a new technology for monitoring of deterioration in material properties and diagnostics of damage. The application field now includes both the nonlinear wave and nonlinear vibration modes. The former is based on the assumption and is applicable to the case studies of the distributed material nonlinearity. It profits from accumulation of the wave nonlinear response along the propagation distance and relies on the higher harmonic signals. A strong nonlinear response of non-bonded interfaces in planar defects introduces the nonlinearity localized in the defect area where the vibration nonlinearity steps up. The concept of local defect resonance (LDR) combined with its nonlinearity identifies a nonlinear inclusion as a nonlinear oscillator and brings about different dynamic and frequency scenarios in vibration nonlinear phenomena. The LDR-induced trapping of the nonlinearity generates a defect-selective nonlinearity and conditions for efficient and even noncontact nonlinear diagnostic imaging of damage.