TY - CONF A1 - Völker, Christoph T1 - Understanding distributed data – a semantic web approach for data based analysis of NDT data in civil engineering N2 - In the field of non-destructive testing (NDT) in civil engineering, a large number of measurement data are collected. Although they serve as a basis for scientific analyses, there is still no uniform representation of the data. An analysis of various distributed data sets across different test objects is therefore only possible with high manual effort. We present a system architecture for an integrated data management of distributed data sets based on Semantic Web technologies. The approach is essentially based on a mathematical model - the so-called ontology - which represents the knowledge of our domain NDT. The ontology developed by us is linked to data sources and thus describes the semantic meaning of the data. Furthermore, the ontology acts as a central concept for database access. Non-domain data sources can be easily integrated by linking them to the NDT construction ontology and are directly available for generic use in the sense of digitization. Based on an extensive literature research, we outline the possibilities that this offers for NDT in civil engineering, such as computer-aided sorting, analysis, recognition and explanation of relationships (explainable AI) for several million measurement data. The expected benefits of this approach of knowledge representation and data access for the NDT community are an expansion of knowledge through data exchange in research (interoperability), the scientific exploitation of large existing data sources with data-based methods (such as image recognition, measurement uncertainty calculations, factor analysis, material characterization) and finally a simplified exchange of NDT data with engineering models and thus with the construction industry. Ontologies are already the core of numerous intelligent systems such as building information modeling or research databases. This contribution gives an overview of the range of tools we are currently creating to communicate with them. T2 - EGU General Assembly 2020 CY - Online meeting DA - 04.05.2020 KW - Ontology KW - NDT KW - Concrete KW - Onotology KW - Semantic Data Management KW - Reproducible Science PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518076 DO - https://doi.org/10.5194/egusphere-egu2020-19332 AN - OPUS4-51807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Tobias T1 - Laser Induced Breakdown Spectroscopy A Tool for Imaging the Chemical Composition of Concrete N2 - One of the most common causes of damage is the ingress of harmful ions into the concrete, which can lead to deterioration processes and affect structural performance. Therefore, the increasingly aging infrastructure is regularly inspected to assess durability. Regular chemical analysis can be useful to determine the extent and evolution of ion ingress and to intervene in a timely manner. This could prove more economical than extensive repairs for major damage, particularly for critical infrastructure. In addition to already established elemental analysis techniques in civil engineering such as potentiometric titration or X-ray fluorescence analysis, laser-induced breakdown spectroscopy (LIBS) can provide further important complementary information and benefits. The possibilities of LIBS are demonstrated using the example of a drill core taken from a parking garage. T2 - 6th International Conference on Concrete Repair, Rehabilitation and Retrofitting CY - Cape Town, South Africa DA - 03.10.2022 KW - LIBS KW - Concrete KW - Cement KW - Chlorine PY - 2022 AN - OPUS4-56061 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilsch, Gerd A1 - Völker, Tobias A1 - Klewe, Tim A1 - Kruschwitz, Sabine T1 - Laser Induced Breakdown Spectroscopy – A Tool for Imaging the Chemical Composition of Concrete N2 - One of the most common causes of damage is the ingress of harmful ions into the concrete, which can lead to deterioration processes and affect structural performance. Therefore, the increasingly aging infrastructure is regularly inspected to assess durability. Regular chemical analysis can be useful to determine the extent and evolution of ion ingress and to intervene in a timely manner. This could prove more economical than extensive repairs for major damage, particularly for critical infrastructure. In addition to already established elemental analysis techniques in civil engineering such as potentiometric titration or X-ray fluorescence analysis, laser-induced breakdown spectroscopy (LIBS) can provide further important complementary information and benefits. The possibilities of LIBS are demonstrated using the example of a drill core taken from a parking garage. T2 - 6th International Conference on Concrete Repair, Rehabilitation and Retrofitting CY - Kapstadt, South Africa DA - 03.10.2022 KW - LIBS KW - Concrete KW - Chlorine PY - 2022 UR - https://iccrrr2022.org/downloads SP - 126 EP - 127 AN - OPUS4-56062 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilsch, Gerd T1 - Laser induced breakdown spectroscopy to investigate the chemical composition of concrete N2 - Laser-induced breakdown spectroscopy (LIBS) is a spectroscopic method for detecting the chemical composition of optically accessible surfaces. In principle, the measurement of all elements of the periodic table is possible. System calibrations allow the quantification of element concentrations. In combination with scanner systems, the two-dimensional element distribution can be determined. Even rough surfaces can be measured by online adjustment of the laser focus. To detect element ingress into the concrete, typically cores are taken, cut in half, and LIBS measurements are performed on the cross-section. The high spatial resolution as well as the simultaneous multi-element analysis enables a separate evaluation of the binder-matrix and aggregates. Therefore, the element concentrations can be determined directly related to the cement paste. LIBS measurements are applicable in the laboratory, on-site and also over a distance of several meters. Common applications include the investigation of material deterioration due to the ingress of harmful ions and their interaction in porous building materials. LIBS is able to provide precise input parameters for simulation and modelling of the remaining lifetime of a structure. Besides the identification of materials, also their composition can be determined on hardened concrete, such as the type of cement or type of aggregate. This also involves the identification of environmentally hazardous elements contained in concrete. Another possible application is the detection of the composition of material flows during dismantling. Non-contact NDT for “difficult to assess” structures as an example application through safety glass or in combination with robotics and automation are also possible. This work presents the state of the art concerning LIBS investigations on concrete by showing exemplary laboratory and on-site applications. T2 - NDE NucCon 2023 CY - Espoo, Finland DA - 25.01.2023 KW - LIBS KW - Concrete PY - 2023 AN - OPUS4-57323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilsch, Gerd A1 - Völker, Tobias A1 - Klewe, Tim A1 - Kruschwitz, Sabine T1 - Laser-induced breakdown spectroscopy to investigate the chemical composition of concrete N2 - Laser-induced breakdown spectroscopy (LIBS) is a spectroscopic method for the analysis of the chemical composition of sample materials. Generally, the measurement of all elements of the periodic table is possible. In particular, light elements such as H, Li, Be, S, C, O, N and halogens can be measured. Calibration with matrix-matching standards allows the quantification of element concentrations. In combination with scanner systems, the two-dimensional element distribution can be determined. Even rough surfaces can be measured by online adjustment of the laser focus. LIBS can also be used on-site with mobile systems. Hand-held systems are available for point measurements. Common applications include the investigation of material deterioration due to the ingress of harmful ions and their interaction in porous building materials. Due to the high spatial resolution of LIBS and the consideration of the heterogeneity of concrete, the determination of precise input parameters for simulation and modelling of the remaining lifetime of a structure is possible. In addition to the identification of materials, it is also possible to assess the composition for example of hardened concrete, which involves the cement or aggregate type used. Other important fields of application are the detection of environmentally hazardous elements or the material classification for sorting heterogeneous material waste streams during dismantling. Non-contact NDT for “difficult to assess” structures as an example application through safety glass or in combination with robotics and automation are also possible. In this work, an overview of LIBS investigations on concrete is given based on exemplary laboratory and on-site applications. T2 - NDE NucCon 2023 CY - Espoo, Finland DA - 25.01.2023 KW - LIBS KW - Concrete KW - Chemical analysis PY - 2023 UR - https://www.aalto.fi/en/nde-nuccon-2023 SP - 351 EP - 359 AN - OPUS4-57303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jablonka, Kevin Maik A1 - Ai, Qianxiang A1 - Al-Feghali, Alexander A1 - Badhwar, Shruti A1 - Bocarsly, Joshua D. A1 - Bran, Andres M. A1 - Bringuier, Stefan A1 - Brinson, L. Catherine A1 - Choudhary, Kamal A1 - Circi, Defne A1 - Cox, Sam A1 - de Jong, Wibe A. A1 - Evans, Matthew L. A1 - Gastellu, Nicolas A1 - Genzling, Jerome A1 - Gil, María Victoria A1 - Gupta, Ankur K. A1 - Hong, Zhi A1 - Imran, Alishba A1 - Kruschwitz, Sabine A1 - Labarre, Anne A1 - Lála, Jakub A1 - Liu, Tao A1 - Ma, Steven A1 - Majumdar, Sauradeep A1 - Merz, Garrett W. A1 - Moitessier, Nicolas A1 - Moubarak, Elias A1 - Mouriño, Beatriz A1 - Pelkie, Brenden A1 - Pieler, Michael A1 - Ramos, Mayk Caldas A1 - Ranković, Bojana A1 - Rodriques, Samuel G. A1 - Sanders, Jacob N. A1 - Schwaller, Philippe A1 - Schwarting, Marcus A1 - Shi, Jiale A1 - Smit, Berend A1 - Smith, Ben E. A1 - Van Herck, Joren A1 - Völker, Christoph A1 - Ward, Logan A1 - Warren, Sean A1 - Weiser, Benjamin A1 - Zhang, Sylvester A1 - Zhang, Xiaoqi A1 - Zia, Ghezal Ahmad Jan A1 - Scourtas, Aristana A1 - Schmidt, K. J. A1 - Foster, Ian A1 - White, Andrew D. A1 - Blaiszik, Ben T1 - 14 examples of how LLMs can transform materials science and chemistry: a reflection on a large language model hackathon N2 - Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines. KW - Large Language model KW - Hackathon KW - Concrete KW - Prediction KW - Inverse Design KW - Orchestration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589961 DO - https://doi.org/10.1039/d3dd00113j VL - 2 IS - 5 SP - 1233 EP - 1250 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Christoph A1 - Kruschwitz, Sabine T1 - Accelerating the search for sustainable concretes with AI N2 - With 8% of man-made CO2 emissions, cement production is an important driver of the climate crisis. By using alkali-activated binders, part of the energy-intensive clinker production process can be dispensed. However, as numerous raw materials are involved in the manufacturing process here, the complexity of the materials increases by orders of magnitude. Finding a properly balanced binder formulation is like looking for a needle in a haystack. We have shown for the first time that artificial intelligence (AI)-based optimization of alkali-activated binder formulations can significantly accelerate research. The "Sequential Learning App for Materials Discovery" (SLAMD) aims to accelerate practice transfer. With SLAMD, materials scientists have low-threshold access to AI through interactive and intuitive user interfaces. The value added by AI can be determined directly. For example, the CO2 emissions saved per ton of cement can be determined for each development cycle: the more efficient the AI optimization, the greater the savings. Our material database already includes more than 120,000 data points of alternative binders and is constantly being expanded with new parameters. We are currently driving the enrichment of the data with a life cycle analysis of the building materials. Based on a case study we show how intuitive access to AI can drive the adoption of techniques that make a real contribution to the development of resource-efficient and sustainable building materials of the future and make it easy to identify when classical experiments are more efficient. T2 - fib International Congress CY - Oslo, Norway DA - 12.06.2022 KW - Machine Learning KW - Materials Design KW - Sequential Learning KW - Materials Discovery KW - Concrete PY - 2022 AN - OPUS4-56635 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Völker, Christoph A1 - Moreno Torres, Benjami T1 - SLAMD-FIB-Case-Study N2 - With 8% of man-made CO2 emissions, cement production is an important driver of the climate crisis. By using alkali-activated binders part of the energy-intensive clinker production process can be dispensed with. However, because numerous chemicals are involved in the manufacturing process here, the complexity of the materials increases by orders of magnitude. Finding a properly balanced cement formulation is like looking for a needle in a haystack. We have shown for the first time that artificial intelligence (AI)-based optimization of cement formulations can significantly accelerate research. The „Sequential Learning App for Materials Discovery“ (SLAMD) aims to accelerate practice transfer. With SLAMD, materials scientists have low-threshold access to AI through interactive and intuitive user interfaces. The value added by AI can be determined directly. For example, the CO2 emissions saved per ton of cement can be determined for each development cycle: the more efficient the AI optimization, the greater the savings. Our material database already includes more than 120,000 data points of alternative cements and is constantly being expanded with new parameters. We are currently driving the enrichment of the data with a life cycle analysis of the building materials. Based on a case study we show how intuitive access to AI can drive the adoption of techniques that make a real contribution to the development of resource-efficient and sustainable building materials of the future and make it easy to identify when classical experiments are more efficient. KW - Alkali activated concrete KW - Concrete PY - 2022 UR - https://github.com/BAMcvoelker/SLAMD-FIB-Case-Study#slamd-fib-case-study PB - GitHub CY - San Francisco, CA, USA AN - OPUS4-56637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Verbesserung der Kreislaufwirtschaft im Bauwesen durch Bauwerksdiagnose: Ein Einblick in das Projekt REINCARNATE N2 - Das EU-finanzierte Projekt REINCARNATE, im Rahmen des Horizont Europa Programms, setzt neue Maßstäbe in der Kreislaufwirtschaft des Bauwesens durch den Einsatz fortschrittlicher Bauwerksdiagnose-Tools. Diese Werkzeuge, insbesondere die Zerstörungsfreie Prüfung (ZfP), spielen eine zentrale Rolle bei der Förderung der Zirkularität in der Baubranche. Die ZfP ermöglicht es, die Qualität und Eignung von Baumaterialien präzise zu bestimmen, ohne diese zu beschädigen. Dies ist entscheidend für die Wiederverwendung und das Recycling von Baustoffen und trägt wesentlich zur Reduzierung des Bauabfalls bei. Durch die Integration dieser Technologie in die Planungs- und Entwurfsphase können Architekten und Ingenieure aktiv einen nachhaltigeren Bauprozess fördern. REINCARNATE verbindet diese Diagnosemethoden mit digitalen Innovationen wie der Technologie des digitalen Zwillings und KI-gesteuerten Lösungen. Diese Kombination ermöglicht eine noch genauere und effizientere Bewertung und Nutzung von Baustoffen, was die Wiederverwendbarkeit und das Recycling verbessert. Im Rahmen des Projekts werden elf Demonstrationsprojekte in ganz Europa umgesetzt, die die praktische Anwendung dieser Technologien zeigen. Diese Projekte demonstrieren, wie ZfP und digitale Werkzeuge zusammenwirken, um Materialien, die traditionell als Abfall angesehen werden, in wertvolle Ressourcen umzuwandeln. Das Ziel von REINCARNATE ist eine 80-prozentige Verringerung der Bauabfälle und eine 70-prozentige Reduzierung des CO2-Fußabdrucks. Mit diesem Beitrag demonstrieren wir eine klare, umsetzbare Anleitung für die Bauindustrie, wie Innovationen in die Praxis umgesetzt werden können. Wir präsentieren greifbare Strategien zur Implementierung nachhaltiger, zirkulärer Praktiken im Bauwesen und markiert einen Wendepunkt in Richtung einer nachhaltigeren Bauindustrie. T2 - Fachtagung Bauwerksdiagnose 2024 CY - Berlin, Germany DA - 29.02.2024 KW - Concrete KW - Recycling KW - BIM KW - AI KW - NDT PY - 2024 AN - OPUS4-60620 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Tobias T1 - Laser-Induced Breakdown Spectroscopy for Concrete Analysis: Applications and Practical Benefits N2 - Reinforced concrete structures are exposed not only to mechanical loads but also to chemical degradation, which can significantly impact their longevity and performance. Effective assessment and maintenance require a detailed understanding of the ingress of harmful species, such as chlorides or sulfates. Traditional analysis methods, like wet chemical analysis of drill dust or ground core samples, often require homogenization leading to the loss of crucial spatial information in sub-millimeter regions such as localized high concentrations of elements, e.g. in cracks. Laser-induced breakdown spectroscopy (LIBS) offers a cutting-edge solution, providing rapid, multi-element analysis with high spatial resolution from micrometer to millimeter scales. LIBS is capable of detecting both light and heavy elements, making it a powerful tool for detailed concrete analysis. Despite its clear advantages, LIBS is not commonly used in civil engineering. This presentation will showcase practical examples demonstrating the effectiveness and advantages of LIBS in concrete analysis, highlighting real-world applications provided by members of the “LIBS” subcommittee of the technical committee “Civil-Engineering” of the German Society for Non-Destructive Testing (DGZfP). Key examples will be discussed, including measurements from car parks or bridges, alongside an introduction to the newly released DGZfP leaflet B14 providing guidelines for the quantitative determination of chlorine content in concrete by LIBS. Furthermore, prospective applications of LIBS including material identification and classification for concrete recycling, and other emerging uses in civil engineering, will also be presented, showcasing the versatility and future potential of this technology. T2 - Conference on durability of building materials and systems in the transportation infrastructure CY - Mendrisio, Switzerland DA - 22.03.2025 KW - LIBS KW - Spectroscopy KW - Concrete KW - Structural Diagnostics PY - 2025 AN - OPUS4-62822 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dalichow, Dirk A1 - Wilsch, Gerd A1 - Völker, Tobias T1 - Laser Induced Breakdown Spectroscopy for the Chemical Investigation of Concrete—Status of Practical Application N2 - The assessment and maintenance of reinforced concrete structures depends largely on knowledge of the chloride content and chloride ingress. Common methods are the wet chemical analysis of drill dust or powder from ground drill core segments. However, due to the homogenization process, this approach often fails to detect locally elevated chloride levels. A state-of-the-art alternative method is laser-induced breakdown spectroscopy (LIBS), which offers rapid analysis and the possibility of detecting several chemical elements simultaneously. This method is particularly characterized by its ability to measure light elements such as hydrogen, carbon or sodium. The spatial resolution of LIBS is usually 0.25 mm but can be increased to 0.1 mm or less if required. BARG, is the first commercial building materials laboratory in Germany to use LIBS in practice. The current LIBS setup enables rapid, spatial quantification of the chlorine content and at the same time the creation of element maps that visually represent the distribution of essential elements in the concrete. This method can be used to localize areas of elevated chlorine content, particularly in cracks or near reinforcing bars. With the ability to analyze several elements simultaneously, LIBS can determine measurement points associated with the cement phase and, taking into account the water content, relate the measured contents directly to the cement mass. The detailed ingress profiles determined by LIBS provide essential data for the estimation of accurate chlorine diffusion coefficients, which are crucial for probabilistic lifetime predictions. The estimation of the carbon distribution enables the localization of carbonated regions and their effect on the chloride distribution. The possibility of quantitatively determining the sulfur distribution also indicates areas that are affected by a possible sulfate attack. The presentation uses practical examples to demonstrate the possibilities and advantages of the LIBS method. In addition, the newly published leaflet B14 of the German Society for Non-Destructive Testing (DGZfP) will be presented, which describes the use of LIBS for the quantitative determination of chloride content in concrete. T2 - ICCRRR 2024 CY - Cape Town, South Africa DA - 04.11.2024 KW - Concrete KW - Chloride KW - Corrosion KW - Repair KW - Maintenance PY - 2024 DO - https://doi.org/10.1007/978-3-031-75507-1_40 VL - 59 SP - 411 EP - 420 AN - OPUS4-62480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dalichow, Dirk T1 - Laser Induced Breakdown Spectroscopy (LIBS) for the chemical investigation of concrete- Status of practical application and regulations in Germany N2 - The assessment and maintenance of reinforced concrete structures depends largely on knowledge of the chloride content and chloride ingress. Common methods are the wet chemical analysis of drill dust or powder from ground drill core segments. However, due to the homogenization process, this approach often fails to detect locally elevated chloride levels. A state-of-the-art alternative method is laser-induced breakdown spectroscopy (LIBS), which offers rapid analysis and the possibility of detecting several chemical elements simultaneously. This method is particularly characterized by its ability to measure light elements such as hydrogen, carbon or sodium. The spatial resolution of LIBS is usually 0.25 mm but can be increased to 0.1 mm or less if required. BARG, is the first commercial building materials laboratory in Germany to use LIBS in practice. The current LIBS setup enables rapid, spatial quantification of the chlorine content and at the same time the creation of element maps that visually represent the distribution of essential elements in the concrete. This method can be used to localize areas of elevated chlorine content, particularly in cracks or near reinforcing bars. With the ability to analyze several elements simultaneously, LIBS can determine measurement points associated with the cement phase and, taking into account the water content, relate the measured contents directly to the cement mass. The detailed ingress profiles determined by LIBS provide essential data for the estimation of accurate chlorine diffusion coefficients, which are crucial for probabilistic lifetime predictions. The estimation of the carbon distribution enables the localization of carbonated regions and their effect on the chloride distribution. The possibility of quantitatively determining the sulfur distribution also indicates areas that are affected by a possible sulfate attack. The presentation uses practical examples to demonstrate the possibilities and advantages of the LIBS method. In addition, the newly published leaflet B14 of the German Society for Non-Destructive Testing (DGZfP) will be presented, which describes the use of LIBS for the quantitative determination of chloride content in concrete. T2 - ICCRRR 2024 CY - Cape Town, South Africa DA - 04.11.2024 KW - Concrete KW - Chloride KW - Corrosion KW - Repair KW - Maintenance PY - 2024 AN - OPUS4-62481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Christoph A1 - Kruschwitz, Sabine A1 - Moreno Torres, Benjami A1 - Firdous, R. A1 - Zia, G. J. A. A1 - Stephan, D. T1 - Accelerating the search for alkali-activated cements with sequential learning N2 - With 8% of man-made CO2 emissions, cement production is an important driver of the climate crisis. By using alkali-activated binders, part of the energy-intensive clinker production process can be dispensed. However, as numerous raw materials are involved in the manufacturing process here, the complexity of the materials increases by orders of magnitude. Finding a properly balanced binder formulation is like looking for a needle in a haystack. We have shown for the first time that artificial intelligence (AI)-based optimization of alkali-activated binder formulations can significantly accelerate research. The "Sequential Learning App for Materials Discovery" (SLAMD) aims to accelerate practice transfer. With SLAMD, materials scientists have low-threshold access to AI through interactive and intuitive user interfaces. The value added by AI can be determined directly. For example, the CO2 emissions saved per ton of cement can be determined for each development cycle: the more efficient the AI optimization, the greater the savings. Our material database already includes more than 120,000 data points of alternative binders and is constantly being expanded with new parameters. We are currently driving the enrichment of the data with a life cycle analysis of the building materials. Based on a case study we show how intuitive access to AI can drive the adoption of techniques that make a real contribution to the development of resource-efficient and sustainable building materials of the future and make it easy to identify when classical experiments are more efficient. T2 - fib International Congress CY - Oslo, Norway DA - 12.06.2022 KW - Concrete KW - Materials Design KW - Sequential Learning KW - Machine Learning PY - 2022 SP - 1 EP - 9 AN - OPUS4-56634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst T1 - Elastic Reverse Time Migration for Improved Ultrasonic Imaging of Concrete Constructions N2 - The ageing concrete infrastructure worldwide requires a thorough inspection and assessment. The traditional visual and tap testing methods required by many national and international standard have been meanwhile amended by more sophisticated tools like ultrasonic or radar echo technologies. While they can provide a much more detailed image of the interiors of concrete constructions, there are still several unsolved testing tasks on the wish list, such as the reliable sizing of internal objects, e.g. tendon ducts. Reverse Time Migration (RTM) is an imaging technique which is in use in the oil and gas industry for the exploration of new resources with seismic waves as a standard tool. Since about ten years there has been R&D effort to use RTM for imaging of ultrasonic echo data. As it uses the entire wavefield, RTM has some advantages compared to traditional SAFT, e.g. the ability to image vertical structures or the backside of objects. However, this comes with the cost of having to perform full wavefield simulations. We have adopted, improved, and used open source 2D full elastic codes (P/SV waves and SH waves) from geophysics to evaluate the capabilities and limitations of RTM for the imaging of certain features in concrete constructions. We can show the advantages of SH-wave RTM in comparison to SAFT, acoustic RTM and P/SV-based RTM. The findings are demonstrated based on simulated and real data, using a reference test specimen available at BAM. Position and diameter of tendon ducts have been determined with a sub-cm accuracy. T2 - ISNT NDE 2024 CY - Chennai, India DA - 12.12.2024 KW - NDT-CE KW - Ultrasound KW - Imaging KW - Reverse Time Migration KW - Concrete KW - RTM PY - 2024 AN - OPUS4-62203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ukrainczyk, Neven A1 - Bernard, Thomas A1 - Babaahmadi, Arezou A1 - Huang, Liming A1 - Zausinger, Christoph A1 - Soive, Anthony A1 - Bonnet, Stéphanie A1 - Georget, Fabien A1 - Mrak, Maruša A1 - Dolenec, Sabina A1 - Völker, Tobias A1 - Suraneni, Prannoy A1 - Wilson, William T1 - Test methods for chloride diffusivity of blended cement pastes: a review by RILEM TC 298-EBD N2 - The use of supplementary cementitious materials (SCM) is an important part of the roadmap for reducing CO2 emissions and extending the service life of reinforced concrete structures. To accelerate the adoption of SCMs, the RILEM Technical Committee 298-EBD evaluates scaled-down cement paste test methods to assess the effect of SCM on resistance to chloride and sulfate ingress and reactivity, which are critical to concrete durability. This review focuses on methods for measuring chloride diffusivity and is divided into four sections: diffusivity models and parameters, diffusion test methods (including NMR and chloride measurements), migration test methods and implications for future research. Key insights highlight the complexities of multi-species ionic and molecular diffusion/migration, including various binding interactions, and compares the different measurement methodologies. The review also addresses the test scale and aggregate effects, noting the pros and cons of testing at the paste, mortar, and concrete scales. The review underscores the need for further investigation into testing protocols and the influence of SCM on chloride diffusion, emphasizing that comprehensive testing across different scales provides complementary information for assessing durability performance. KW - Chloride ingress KW - Diffusion tests KW - Migration test KW - Cement paste KW - Concrete KW - Supplementary cementitious materials (SCM) PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-645889 DO - https://doi.org/10.1617/s11527-025-02809-4 SN - 1359-5997 VL - 58 IS - 10 SP - 1 EP - 35 PB - Springer Science and Business Media LLC AN - OPUS4-64588 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -