TY - RPRT A1 - Krause, Martin A1 - Mayer, K. A1 - Ballier, G. A1 - Borchardt, Kerstin A1 - Chinta, P.K. A1 - Effner, Ute A1 - Milmann, Boris A1 - Müller, Sabine A1 - Nowak, Thomas Rudolf T1 - Hochgenaue Strukturerkennung von Holzbauteilen mit 3D-Ultraschall N2 - Inhalt ist die zerstörungsfreie Detailuntersuchung von Holzbauteilen mit einem dreidimensional abbildenden Ultraschall-Echoverfahren. Das neu entwickelte 3D-Verfahren berücksichtigt den anisotropen Aufbau des Holzes. Die Bildschnitte und Projektionen werden aus flächigen Ultraschallaufnahmen berechnet. Die Messungen erfolgen an Probekörpern sowie an Bauteilen aus der Praxis. In dem Forschungsvorhaben wird die für Holz neue 3D-Rekonstruktionsrechnung verwendet und mit dem Ziel weiterentwickelt, unter Berücksichtigung der anisotropen Struktur des Holzes eine dreidimensional aufgelöste Abbildung von Reflektoren im Inneren der Holzbauteile zu ermöglichen. Damit werden die bisher für Holzbauteile zur Verfügung stehenden Verfahren entscheidend ergänzt, weil nun eine hochgenaue dreidimensionale Abbildung erreichbar ist (Auflösung: 20 mm und besser). KW - Ultraschallecho-Verfahren KW - Holzbauteile KW - Abbildungsverfahren KW - Imaging PY - 2014 UR - https://www.irb.fraunhofer.de/bauforschung/baufolit/projekt/Hochgenaue-Strukturerkennung-von-Holzbauteilen-mit-3D-Ultraschall/20138035979 SN - 978-3-8167-9212-3 VL - 109 SP - 1 EP - 101 PB - Fraunhofer IRB Verl. CY - Stuttgart AN - OPUS4-32852 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chinta, P.K. A1 - Mayer, K. A1 - Krause, Martin T1 - Ultraschallmodellierung und SAFT-Rekonstruktion von Fehlstellen in Holzbauteilen T2 - DGZfP-Jahrestagung 2010 CY - Erfurt, Deutschland DA - 2010-05-10 KW - Ultraschallecho KW - Holz KW - SAFT PY - 2010 SN - 978-3-940283-26-9 IS - DGZfP-BB 122 (Poster 59) SP - 1 EP - 8 CY - Berlin AN - OPUS4-22899 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, Martin A1 - Milmann, Boris A1 - Mielentz, Frank A1 - Streicher, Doreen A1 - Redmer, Bernhard A1 - Mayer, K. A1 - Langenberg, K.-J. A1 - Schickert, M. T1 - Ultrasonic Imaging Methods for Investigation of Post-tensioned Concrete Structures: A Study of Interfaces at Artificial Grouting Faults and Its Verification N2 - This paper presents the progress of successful location of grouting faults in tendon ducts with ultrasonic imaging. The examples were obtained in the research group FOR 384 funded by DFG (German Research Foundation). The co-operation of experimental research and modeling allowed imaging and identification of grouted and ungrouted areas of tendon ducts (including strands) in a large test specimen (40 m²). In addition to the criteria for indicating grouting faults in post-tensioned ducts known until now the phase evaluation of reflected ultrasonic pulses is described. Experiments and modeling of wave propagation are presented for reflections at metal plates in concrete (thickness range 0.5 mm to 40 mm) and for tendon ducts including strands. The main part of the progress was achieved by automated measurements using dry contact transducers, 3D-SAFT reconstruction including phase evaluation and modeling considering wave propagation for typical elastic parameters and exact experimental site conditions. The results for shear waves as well as for pressure waves are compared in the frequency range from 50 kHz to 120 kHz. KW - Non-destructive testing KW - Tendons KW - Prestressed concrete bridges KW - Ultrasonic echo KW - Reconstruction calculation KW - 3D-SAFT KW - Modeling (EFIT) PY - 2008 DO - https://doi.org/10.1007/s10921-008-0033-5 SN - 0195-9298 SN - 1573-4862 VL - 27 IS - 1-3 SP - 67 EP - 82 PB - Plenum Press CY - New York, NY AN - OPUS4-17922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mayer, K. A1 - Langenberg, K.-J. A1 - Krause, Martin A1 - Milmann, Boris A1 - Mielentz, Frank T1 - Characterization of reflector types by phase-sensitive ultrasonic data processing and imaging N2 - Ultrasonic and radar imaging techniques are limited in resolution by the wavelength in the material, yet information beyond those limits is hidden in complex frequency dependent reflection coefficients. The analysis of the phase of complex reflection coefficients together with the properties of imaging algorithms can help to characterize and to classify indications of defects in concrete buildings. This paper describes a method to extract phase information from measurements and SAFT reconstructed images. The influencing factors like material properties, transducer characteristics, and imaging algorithms based on Born or Physical Optics approximations are elaborated. Simulated and experimental results are briefly discussed. KW - NDT KW - Imaging KW - Flaw characterization KW - Tendon ducts KW - Phase analysis KW - Ultrasonic echo KW - SAFT KW - FT-SAFT KW - EFIT-modeling KW - Modellierung KW - EFIT KW - Spannbeton KW - Ultraschallecho KW - Spannkanäle KW - Verpressfehler KW - Zerstörungsfreie Prüfung im Bauwesen KW - ZfP-Bau PY - 2008 DO - https://doi.org/10.1007/s10921-008-0035-3 SN - 0195-9298 SN - 1573-4862 VL - 27 IS - 1-3 SP - 35 EP - 45 PB - Plenum Press CY - New York, NY AN - OPUS4-17926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayer, K. A1 - Langenberg, K.-J. A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Milmann, Boris A1 - Kohl, Christoph T1 - Characterization of ultrasonic and radar reflector types in concrete by phase evaluation of the signal and the reconstructed image T2 - 9th European Conference on NDT CY - Berlin, Germany DA - 2006-09-25 KW - NDT-CE KW - Ultrasonic echo KW - Radar KW - Phase evaluation KW - Modeling of wave propagation KW - Reconstruction calculation PY - 2006 SN - 3-931381-86-2 SP - 1 EP - 8(?) PB - European Federation for Non-Destructive Testing CY - Berlin AN - OPUS4-14225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, Martin A1 - Mayer, K. A1 - Chinta, P.K. A1 - Effner, Ute T1 - Ultrasonic imaging of defects in building elements made from timber N2 - There is a great demand for non-destructive testing methods for quality assurance and to assess the safety and durability of wooden structures. Ultrasonic echo technique with shear waves in the frequency range of 50 kHz is one of those promising methods and is already frequently applied for usual and glued laminated timber. The article describes the development and first results for an imaging method for this purpose. The highly anisotropic properties of the ultrasonic velocity have to be considered. A 3D-SAFT (Synthetic Aperture Focusing Technique) imaging scheme is developed initially for synthetic data resulting from modelling the elastic wave propagation. The main part of the paper describes the experimental validation of this evaluation technique by experimental studies applying automated ultrasonic scanning techniques. 3D ultrasonic imaging results are described for test specimens made from pine and spruce wood. Another object of investigation was a pedestrian bridge made from siberian larch. KW - Ultrasonic echo KW - Imaging KW - SAFT reconstruction calculation KW - Anisotropic wave propagation KW - EFIT modelling KW - Glued-laminated timber (glulam) PY - 2013 DO - https://doi.org/10.4028/www.scientific.net/AMR.778.312 SN - 1022-6680 SN - 1662-8985 VL - 778 SP - 312 EP - 320 PB - Trans Tech Publ. CY - Zurich AN - OPUS4-29088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ballier, G. A1 - Mayer, K. A1 - Langenberg, K.-J. A1 - Schulze, Sebastian A1 - Krause, Martin T1 - Improvement on tendon duct examination by modelling and imaging with synthetic aperture and one-way inverse methods N2 - The knowledge of the internal structure of tendon ducts is one of the important preconditions to make predictions about the stableness and the lifetime of concrete buildings – specifically concrete bridges. Ultrasonic NDT methods can be used to have a look inside those components. To understand the complex effects resulting from elastic wave propagation, it is important to build test specimens and to analyze the measurements with the aid of modelling. At BAM (German Federal Institute for Materials Research and Testing) a new specimen is under construction to realize some of the most common geometrical structures which can be expected in the field of tendon duct testing in concrete bridges. We present various measurement concepts and a comparison between measurement and modelling with EFIT (Elastic Finite Integration Technique), as well as results of imaging methods based on conventional SAFT (Synthetic Aperture Focusing Technique) or FT-SAFT (SAFT with Fourier Techniques) together with phase evaluation. In addition we will present the results of time reversal using AFIT (Acoustic Finite Integration Technique) and a one-way wave propagation method to improve the imaging. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - SAFT KW - Ultrasonic NDT KW - Concrete KW - One way KW - AFIT KW - Time reversal PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 8 AN - OPUS4-35102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Mayer, K. A1 - Effner, Ute T1 - Ultrasonic echo methods for structural timber N2 - Ultrasonic echo technique with shear waves in the frequency rang of 50 kHz is one of the promising methods for assessment of structural timber and is already frequently applied for this purpose. The article summarizes the state of the art of applying echo measurement via linear measurements as well as the development and first results for an imaging method for this purpose. The highly anisotropic properties of the ultrasonic velocity have to be considered. 3 D ultrasonic imaging results are described for the example of a pedestrian bridge made from Siberian larch. T2 - COST Workshop - Highly performing timber structures: Reliability, assessment, monitoring and strengthening CY - Biel, Switzerland DA - 23.09.2014 KW - Ultrasonic echo KW - SAFT reconstruction calculation KW - Glued-laminated timber (glulam) KW - Footbridge KW - Ultraschallecho KW - SAFT KW - Brettschichtholz PY - 2014 SN - 978-3-9523787-3-1 SP - 77 EP - 82 PB - Bern University of Applied Sciences CY - Bern AN - OPUS4-35179 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Amano, K.O.A. A1 - Hahn, S.-K. A1 - Tschirschwitz, Rico A1 - Rappsilber, Tim A1 - Krause, U. T1 - Experimental Investigation on Explosion Pressure Characteristics of Lithium-based (NMC) Pouch Batteries during Thermal Runaway N2 - Lithium ion batteries (LIBs) are prone to spontaneous and subsequent fire or explosion resulting from thermal runaway. The vented gases are not only toxic and flammable, their emission can also raise the surrounding pressure rapidly. In this study, characteristic variations of explosion pressure rise, rate of explosion pressure rise and 𝐾(sT)-value have been evaluated. The characteristic 𝐾(𝑠𝑇)-values were determined to evaluate the explosive behavior of LIBs during thermal runaway. The estimated values were compared to that of other explosive substances. T2 - Batterieforum Deutschland 2021 CY - Online meeting DA - 20.01.2021 KW - Pressure KW - Lithium KW - Thermal Runaway KW - Battery KW - Pouch PY - 2021 AN - OPUS4-52033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amano, K. A1 - Hahn, S. A1 - Tschirschwitz, Rico A1 - Rappsilber, Tim A1 - Krause, U. T1 - An Experimental Investigation of Thermal Runaway and Gas Release of NMC Lithium-Ion Pouch Batteries Depending on the State of Charge Level N2 - In this study, 19 experiments were conducted with 25 pouch cells of NMC cathode to investigate thermal runaway and the release of gases from lithium-ion batteries (LIBs). Single cells, double cells, and a four-cell battery stack were forced to undergo thermal runaway inside an air-tight reactor vessel with a volume of 100 dm3 . The study involved two series of tests with two types of ignition sources. In the Series 1 tests, a heating plug was used to initiate thermal runaway in LIBs in the ranges of 80–89% and 90–100% SOC. In the Series 2 tests, a heating plate was used to trigger thermal runaway in LIBs in the ranges of 30–50%, 80–89%, and 90–100% SOC. Thermal runaway started at an onset temperature of 344 ± 5 K and 345 K for the Series 1 tests and from 393 ± 36 K to 487 ± 10 K for the Series 2 tests. Peak reaction temperatures ranged between 642 K and 1184 K, while the maximum pressures observed were between 1.2 bar and 7.28 bar. Thermal runaway induced explosion of the cells and lead to a rate of temperature increase greater than 10 K/s. The amounts of gases released from the LIBs were calculated from pressures and temperatures measured in the reactor. Then, the gas composition was analyzed using a Fourier transform infrared (FTIR) spectrometer. The highest gaseous production was achieved at a range of 90–100% SOC and higher battery capacities 72 L, 1.8 L/Ah (Series 1, battery stack) and 103 L, 3.2 L/Ah (Series 2, 32 Ah cell)). Among the gases analyzed, the concentration of gaseous emissions such as C2H4 , CH4 , and C2H6 increased at a higher cell capacity in both series of tests. The study results revealed characteristic variations of thermal behavior with respect to the type of ignition source used. KW - Lithium-ion batteries KW - Battery KW - Pouch cell KW - NMC Cathode KW - Thermal runaways PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548601 DO - https://doi.org/10.3390/batteries8050041 VL - 8 IS - 5 SP - 1 EP - 16 PB - MDPI CY - Basel, Switzerland AN - OPUS4-54860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zinke, R. A1 - Wothe, K. A1 - Dugarev, D. A1 - Götze, O. A1 - Köhler, F. A1 - Schalau, Sebastian A1 - Krause, U. T1 - Uncertainty consideration in CFD-models via response surface modeling: Application on realistic dense and light gas dispersion simulations N2 - Major accidents in the process industry often lead to the release of light or dense gases, which can mean a thread to employees, local residents or to the environment. Possible scenarios are therefore analyzed and evaluated in advance for approval issues. There is a trend, where simple empirical models are being replaced with more complex numerical models. Gaussian dispersion models or models based on dimensional analysis approaches are for example, increasingly replaced by CFD simulations. The main reason for this is the potentially higher accuracy. However, usually scenarios using sharp parameter values are calculated, since comprehensive consideration of parameter distributions via Monte Carlo or Latin Hypercube Sampling fails due to the numerical effort. This includes the risk that the influence of uncertainties on the simulation results is not taken into account. Response surface methods offer an alternative, with which the CFD problem can be mapped onto an algebraic surrogate model. If this is sufficiently precise, parameter sampling can also be carried out with the surrogate as well, as shown in some publications. Previous investigations only demonstrated the basic principle using trivial dispersion models. In this paper two realistic CFD simulations from the plant safety area are considered: VOC emissions from a storage tank and near-ground dense gas emissions. The entire procedure of response surface determination and parameter studies was automated and parallelized for high-performance-computing, and is carried out on the underlying CFD grids. For the CFD simulations as well as for all visualizations, the commercial software ANSYS CFX and the open source software OpenFOAM were used. The aim of this paper is to demonstrate the method using industry-relevant applications as well as to show how this can be used in practical engineering applications. The quality of surrogate modeling, the numerical effort and advantages that can result from the procedure are discussed as well as advantages which may result from taking parameter uncertainties into account in safety studies. KW - CFD KW - Accidental release KW - Response surface methods KW - Air dispersion modeling PY - 2022 DO - https://doi.org/10.1016/j.jlp.2021.104710 SN - 0950-4230 VL - 75 SP - 1 EP - 10 PB - Elsevier CY - Amsterdam AN - OPUS4-56887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Jansen, D. A1 - Bald, S. A1 - Birbaum, J. A1 - Küttenbaum, Stefan A1 - Krause, J. A1 - Maack, Stefan A1 - Pichottka, S. A1 - Scherkenbach, M. A1 - Strangfeld, Christoph A1 - Villaret, K. A1 - Wöllenstein, J. T1 - Sensors for the structural assessment of roads N2 - This working paper summarises the current state of knowledge and research on the application of sensors in road pavements, designed to record input quantities and characteristics for structural assessment. In this working paper, sensors generally refer to technical equipment that can used to record the values of physical quantities and display them for interpretation. The working paper deals with every type of sensor that is permanently connected to the road, i.e. sensors that are installed – in the bound and unbound courses of the superstructure as well as in the sub-base/sub-structure, – next to or above the road (for example on masts) and can contribute to structural recording and its subsequent assessment. This can also include sensors that are primarily used for a different purpose (e.g. traffic control). However, this working paper only describes the application of sensors that are installed primarily for other purposes for the sake of completeness; special publications (e.g. Notes on detection technologies in road traffic) are available for the respective installation situations. KW - Asphalt KW - Concrete KW - Measurement chain KW - Sensor technology KW - Condition assessment PY - 2024 SP - 1 EP - 36 PB - Forschungsgemeinschaft für Straßen- und Verkehrswesen e.V. CY - Köln AN - OPUS4-60084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulze, S. A1 - Krause, Martin A1 - Mayer, K. A1 - Redmer, Bernhard A1 - Wiggenhauser, Herbert T1 - Grouting defects localized by ultrasonic testing including phase evaluation N2 - Grouting defects, e.g. in post-tensioned structures or piped anchors may be identified by ultrasonic imaging. Since several years experiences are carried out with false color displayed phase values, which enable distinct localization of ungrouted regions. In this contribution we report on progress in localizing grouting defects in tendon ducts, when they are only partly grouted and the unfilled part is not orientated into the direction of the measuring surface. This is frequently the case e.g. for box girder structures. Düring the project specimens containing different types of grouting faults are investigated in Order to optimize measuring and evaluation techniques. A handheld linear array System (commercially available) is applied for fast 2D-measurement and subsequent phase sensitive 3D-imaging (new Software development). In a large concrete wall specimen tendon ducts and real prestressing Systems containing grouting defects were built in. The ducts are partly covered by non prestressed reinforcement bars in order to investigate its disturbing influence. These included objects were investigated afterwards with the described methods. We report on large area measuring results, which were partly verified by y-radiography. In the frame of practical application results of measuring the position and extend of a blockade within a posttensioned structure are presen ted. T2 - SMT 2014 - NDE/NDT for highways and bridges - Structural materials technology CY - Washington, DC, USA DA - 25.08.2014 KW - Ultraschallecho-Verfahren KW - Spannbeton KW - Phasenauswertung PY - 2014 SN - 978-1-57117-342-3 SP - 321 EP - 328 AN - OPUS4-32846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ballier, G. A1 - Mayer, K. A1 - Krause, Martin T1 - Ultraschallabbildung zur zerstörungsfreien Strukturbestimmung von Betonbauteilen mit Hilfe der "One-Way"-Wellengleichung N2 - Die ZfP versucht mit Hilfe von Messdaten, die sie aus z. B. einer Impuls-Echo-Messung gewinnt, Rückschlüsse auf die innere Struktur eines Objektes zu ziehen. Bei Betonbauteilen sollen im Besonderen Verpressfehler, die dann zur Korrosion und damit zur einer Beeinträchtigung der Standsicherheit und Dauerhaftigkeit des Konstruktion (z. B. einer Spannbetonbrücke) führen können, schnell und mit einer hohen Sicherheit aus den Messdaten lokalisiert werden. Das konventionellen SAFT oder FT-SAFT-Verfahren liefern in Verbindung mit einer Phasenauswertung einen schnellen und sicheren Hinweis darauf, dass ein Lufteinschluss/Defekt vorliegt. Darüber hinaus können jedoch Rückausbreitungs-Verfahren, wenn ein gutes Geschwindigkeitsprofil vorliegt, eine wesentlich bessere Lokalisierung des Defekts bieten als SAFT-Verfahren, jedoch mit dem Nachteil, dass sie sehr zeit- und rechenintensiv sind, vor allem im Dreidimensionalen. Als Mittelweg kann hierzu die "One-Way"-Methode dienen. Diese Methode verwendet Pseudo-Differential-Operatoren und ist sehr robust auch bei relativ groben Geschwindigkeitsprofilen. Sie wird an Beispielen aus der Bauwerkdiagnose mit den konventionellen Verfahren verglichen. T2 - DGZfP-Jahrestagung 2011 CY - Bremen, Germany DA - 30.05.2011 KW - Ultraschallecho-Verfahren KW - Betonbauteile KW - Modellierung PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-328714 SN - 978-3-940283-33-7 SP - Poster 66, 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) AN - OPUS4-32871 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, G. A1 - Wehrstedt, Klaus-Dieter A1 - Malow, Marcus A1 - Budde, K. A1 - Mosler, J. T1 - Safe transport of acrylic acid in railroad tank cars. Part 1: Determination of the self-accelerating decomposition temperature N2 - Experiments according to a test specified in the UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, and numerical simulations by means of a finite element method are employed to determine the self-accelerating decomposition temperature of acrylic acid in a railroad tank car. The results demonstrate that the transport of acrylic acid in big tank cars is safe as long as some basic conditions are taken into account. KW - Acrylic acid KW - Dangerous goods KW - Finite element method KW - Railway transport KW - Self-accelerating decomposition temperature PY - 2014 DO - https://doi.org/10.1002/ceat.201300778 SN - 0930-7516 SN - 1521-4125 VL - 37 IS - 9 SP - 1460 EP - 1467 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-31298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulze, S. A1 - Mayer, K. A1 - Krause, Martin T1 - Spannbetonuntersuchung mit bildgebenden Ultraschallecho-Verfahren N2 - Beim Einsatz von Ultraschallecho-Methoden in der zerstörungsfreien Prüfung im Bauwesen stellt die Untersuchung von Spannbetonkonstruktionen eine der anspruchsvollsten Aufgaben für Wissenschaft und Technik dar. Das inhomogene Gefüge aus Beton, schlaffer Bewehrung und – aus Hüllrohr, Spannlitzen und Verpressmörtel bestehenden – Spanngliedern erfordert eine Optimierung von Messtechnik und Auswertesoftware, um verwertbare Aussagen zum Verpresszustand der Hüllrohre zu erhalten. Der vorliegende Beitrag beschreibt die Grundlagen der bildgebenden Darstellung von US-Echo-Daten, die Untersuchung und Datenauswertung an Probekörpern sowie ein Fallbeispiel aus der Praxis. Dabei erweist sich insbesondere die Phasenauswertung zur qualitativen Unterscheidung von Reflektoren als nützlich. Das Prinzip wird erläutert, und es werden Teile eines interaktiven, auf der SAFT-Methode basierenden Softwarepakets vorgestellt. Mit dieser Software können die großflächig gewonnenen Ultraschalldaten auf herkömmlichen PCs oder mobilen Computern zu zwei- und dreidimensionalen Rekonstruktionen berechnet, analysiert und visualisiert werden. Ausgewertet wurden Daten, die mit automatisierten Messsystemen an kleinformatigen Laborprobekörpern und großen Testwänden gewonnen wurden. Im Rahmen der praktischen Anwendung konnten unter Verwendung der vorgestellten Verfahren an einem Spannglied die Lage eines Hüllrohrverstopfers lokalisiert und die Ausdehnung der Blockadestelle eingegrenzt werden.---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Investigation of prestressed concrete using the imaging ultrasonic echo method – Application of phase evaluation for the distinction of reflectors: The application of ultrasound methods for the non-destructive assessment of pre-stressed concrete members is one of the biggest challenges in the field of non-destructive testing in civil engineering. The inhomogeneous composition of concrete, reinforcement and tendons, which itself consist of ducts, steel wires and grouting material, requires an optimisation of measuring technique and analysis software to gain reliable information about the grouting condition of the ducts. This article describes the fundamentals of the visualisation of ultrasound echo data, the investigation and data analysis at specimen and a case study. Here especially the phase evaluation proves to be very useful for the distinction of reflectors. The basic principle is explained and parts of an interactive software module, which is based on the SAFT method, is presented. With this software it is possible to calculate, analyse and visualise 2D and 3D reconstructions of large ultrasound data sets with conventional PCs or mobile computers. Data has been analysed, which were recorded with automatic measurement systems at small scale laboratory specimens and a large scale testing wall. In the frame of the practical application it was possible to localise the position and extent of a blockade within a duct. KW - Ultraschallecho KW - Zerstörungsfreie Prüfung im Bauwesen KW - ZfPBau KW - Ultraschallecho-Methode KW - Bildgebende Auswertung KW - SAFT-Rekonstruktion KW - Phasenauswertung KW - Spannbeton KW - Verpresszustand KW - Rekonstruktionssoftware KW - Non-destructive testing in civil engineering (NDT-CE) KW - Ultrasound echo method KW - Imaging methods KW - SAFT reconstruction KW - Phase evaluation KW - Pre-stressed concrete KW - Grouting condition KW - Reconstruction software KW - Bauwerkserhaltung/Sanierung PY - 2013 DO - https://doi.org/10.1002/best.201300062 SN - 0005-9900 SN - 1437-1006 VL - 108 IS - 12 SP - 845 EP - 853 PB - Ernst CY - Berlin AN - OPUS4-29838 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Griebenow, Werner A1 - Werthmann, Barbara A1 - Treu, Dieter A1 - Hörn, K. A1 - Krause, S. T1 - Zur Identifizierung von Tinten auf alten Handschriften PY - 1983 SN - 0025-1445 SN - 0342-3719 VL - 89 IS - 3 SP - 208 EP - 212 PB - Callwey CY - München AN - OPUS4-38963 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiggenhauser, Herbert A1 - Samokrutov, A.A. A1 - Mayer, K. A1 - Krause, Martin A1 - Alekhin, S. G. A1 - Elkin, V. T1 - LAUS - Large aperture ultrasonic system - for testing thick concrete structures N2 - A Large Aperture UltraSonic (LAUS) system has been designed and built for testing thick concrete structures. The scalable system consists of twelve ultrasonic units, each hosting 32 individual shear wave transducers with mechanical dry point contact (DPC) to the concrete surface. The twelve units are attached to the concrete surface using a vacuum case which holds them in place during operation. Each LAUS unit can be placed individually depending on the surface condition and optimal ultrasonic condition, e.g. rebar position. Air pressure is supplied to each unit through an air hose. The following extended abstract is a short version of an article to be published in the special edition of ASCE JIS that will describe the outline of the system, the principle of functioning, the data processing and adapted reconstruction calculation based on SAFT as well as the system performance during first applications. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 KW - Ultrasonic imaging KW - Linear array KW - Reconstruction calculation (SAFT) PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-345383 UR - http://www.ndt.net/?id=18313 SN - 1435-4934 VL - 20 IS - 11 SP - 1 EP - 4 PB - NDT.net CY - Kirchwald AN - OPUS4-34538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mayer, K. A1 - Milmann, Boris A1 - Krause, Martin A1 - Mielentz, Frank T1 - Methode zum Nachweis von Verpressfehlern in Spannbeton durch Phasenauswertung bei Ultraschallecho-Verfahren KW - Ultraschall-Echo-Verfahren KW - Verpressfehler KW - Spannbeton KW - Hüllrohr KW - Brücken PY - 2008 SN - 1616-069X SN - 0948-5112 VL - 112 IS - 12 SP - 37 EP - 40 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung CY - Berlin AN - OPUS4-18685 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Mayer, K. A1 - Ballier, G. A1 - Friese, Martin A1 - Mielentz, Frank A1 - Milmann, Boris T1 - Darstellung des Verpresszustandes von Spannkanälen mit 3D-Ultraschallechoverfahren: Modellierung und Experiment T2 - DGZfP-Jahrestagung 2010 CY - Erfurt, Deutschland DA - 2010-05-10 KW - Ultraschallecho KW - Rekonstruktionsrechnung KW - SAFT KW - Spannkanäle PY - 2010 SN - 978-3-940283-26-9 IS - DGZfP-BB 122 (Mi.3.B.1) SP - 1 EP - 12 CY - Berlin AN - OPUS4-22900 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krause, Martin A1 - Mayer, K. A1 - Mielentz, Frank A1 - Milmann, Boris A1 - Streicher, Doreen ED - L. Binda, ED - M. di Prisco, ED - R. Felicetti, T1 - New examples for ultrasonic imaging of prestressed concrete elements T2 - 1st International RILEM Conference, - on Site Assessment of Concrete, Masonry and Timber Structures (SACoMaTiS 2008) CY - Varenna, Italy DA - 2008-09-01 KW - Ultrasonic imaging KW - Grouting condition KW - Elastodynamic Finite Integration Technique (EFIT) PY - 2008 SN - 978-2-35158-062-2 VL - 1 IS - PRO 59 SP - 1 EP - 10 PB - RILEM Publications AN - OPUS4-19069 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mielentz, Frank A1 - Boehm, Rainer A1 - Krause, Martin A1 - Mayer, K. T1 - Optimierung von Ultraschall-Prüfkopf-Arrays für die zerstörungsfreie Prüfung im Bauwesen mithilfe von Modellierungen T2 - DGZfP-Jahrestagung 2009 CY - Münster, Deutschland DA - 2009-05-18 KW - Ultraschall KW - Beton KW - Modellierung KW - Schallfeld KW - Punktquellensynthese KW - Elastodynamische Finite Integrationstechnik (EFIT) KW - Prüfkopf KW - Array KW - Gruppenstrahler KW - Phased array PY - 2009 SN - 978-3-940283-16-0 IS - DGZfP-BB 115 (Poster 2) SP - 1 EP - 13 AN - OPUS4-20328 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marklein, R. A1 - Mayer, K. A1 - Zimmer, A. A1 - Krause, Martin T1 - Ganzheitliche Methoden zur zerstörungsfreien Prüfung von Betonbauteilen - Modellierung, Abbildung und Charakterisierung von Verpressfehlern in Hüllrohren N2 - Für die zerstörungsfreie Prüfung großer Betonbauwerke unter dem Aspekt der Analyse von Spannkanälen hat sich die Ultraschalltechnik in den letzten Jahren als geeignete Methode herausgestellt, da sowohl die Messtechnik – insbesondere die Ultraschallwandler – als auch die numerischen Auswerteverfahren in einem Stadium sind, das es erlaubt, größere Messflächen und damit größere Volumina zu beschallen und abzubilden. Mit Hilfe der Modellierung der Ausbreitung elastischer Wellen in komplexen Medien können praxisrelevante Problemstellungen untersucht werden, auch unter dem Aspekt, Testkörper zu planen oder gar zu ersetzen. Durch die Auswertung der Phase der Rekonstruktion eines Streuvorgangs können Fehlstellen klassifiziert und damit Aussagen über die Bauwerkssicherheit signifikant objektiviert werden. Die Methoden werden, im Hinblick auf eine ganzheitliche Sichtweise von skalaren und polarimetrischen Abbildungsverfahren mit Unterstützung der Modellierung und der anschließenden Klassifizierung durch Phasenanalyse, an ausgewählten Beispielen erläutert. For nondestructive testing of concrete buildings under the aspect of tendon duct analysis, ultrasonic testing has proven to be a suitable method, as both the measuring technique – in particular the acoustic sensors – and the numerical methods allow the insonification and imaging of larger surfaces and volumes. With the aid of numerical modelling of elastic wave propagation in complex media real life problems can be examined with the goal to design or even to replace test specimen. By determination of the phase of an imaged scattering event, defects can be classified, and the prediction of the integrity of buildings can be significantly objectified. The methods are explained for selected examples in an integral way with respect to scalar and polarimetric imaging algorithms supported by modelling and subsequent classification through phase analysis. KW - Elastische Wellenausbreitung KW - Numerische Modellierung KW - Polimetrische Abbildungsverfahren KW - Phasenauswertung KW - Beton KW - Spannkanäle KW - Verpressfehler KW - Elastic wave propagation KW - Numerical modelling KW - Polarimetric imaging KW - Phase analysis KW - Concrete KW - Tendon ducts KW - Grouting defects PY - 2008 DO - https://doi.org/10.1524/teme.2008.0868 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 VL - 75 IS - 6 SP - 376 EP - 389 PB - Oldenbourg CY - München AN - OPUS4-18235 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Milmann, Boris A1 - Krause, Martin A1 - Mielentz, Frank A1 - Mayer, K. T1 - Ultraschallecho-Verfahren für Spannbeton: Signifikanter Nachweis von Verpressfehlern mit Phasenauswertung T2 - Fachtagung Bauwerksdiagnose - Praktische Anwendungen Zerstörungsfreier Prüfungen und Zukunftsaufgaben CY - Berlin, Deutschland DA - 2008-02-21 KW - Ultraschallecho KW - Spannbeton KW - Verpressfehler KW - Modellierung KW - Polarimetrische Abbildungsverfahren PY - 2008 SN - 978-3-940283-08-5 N1 - Serientitel: Berichtsband der Deutschen Gesellschaft für Zerstörungsfreie Prüfung – Series title: Berichtsband der Deutschen Gesellschaft für Zerstörungsfreie Prüfung IS - 112 SP - 1 EP - 11 (Beitrag 11) PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung CY - Berlin AN - OPUS4-18280 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Gräfe, Boris A1 - Mielentz, Frank A1 - Milmann, Boris A1 - Friese, Martin A1 - Wiggenhauser, Herbert A1 - Mayer, K. ED - M.G. Alexander, ED - H.-D. Beushausen, ED - F. Dehn, ED - P. Moyo, T1 - Ultrasonic imaging of post-tensioned concrete elements: New techniques for reliable localization of grouting defects T2 - 2nd International Conference on Concrete Repair, Rehabilitation and Retrofitting CY - Cape Town, South Africa DA - 2008-11-24 KW - Post-tensioned concrete KW - Ultrasonic echo KW - Phase evaluation KW - Air-coupled ultrasound PY - 2009 SN - 978-0-415-46850-3 SP - 521 EP - 527 PB - CRC Press CY - Boca Raton AN - OPUS4-20651 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krause, Martin A1 - Mayer, K. A1 - Friese, Martin A1 - Milmann, Boris A1 - Mielentz, Frank A1 - Ballier, G. ED - Odile Abraham, ED - Dérobert, Xavier T1 - Progress in ultrasonic tendon duct imaging T2 - NDTCE `09 - 7th international symposium on non destructive testing in civil engineering CY - Nantes, France DA - 2009-06-30 KW - Reconstruction calculation KW - SAFT KW - EFIT Modelling KW - Prestressed concrete structures PY - 2009 SN - 978-2-7208-2542-5 SN - 1628-4704 IS - Paper 77 SP - 147 EP - 154 AN - OPUS4-20652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Mayer, K. A1 - Wöstmann, Jens A1 - Wiggenhauser, Herbert T1 - 3D-Visualisation of NDT-Data using Data Fusion Technique N2 - Non-destructive testing (NDT) of concrete structures is performed using pulse-echo methods. According to the type of the applied waves it can be classified as acoustic (Impact-Echo, Ultrasonics) and electromagnetic methods (Radar). The results are visualised through different imaging processes. This work is performed in the frame of a research project promoted by Deutsche Forschungsgemeinschaft (FOR384).The objective of data fusion is to use the complementary information of the different methods. Radar can detect metallic reflectors in concrete (metallic ducts and concrete reinforcement) very well. This method is not able to locate defects behind these reflectors (injecting defects, defects behind close concrete reinforcement), because the electromagnetic waves are completely reflected at metals. The acoustic methods are able to compensate this deficit i.e. acoustic waves can penetrate through metal. But acoustic waves in the ultrasonic range are completely reflected by air layers. Air layers have smaller influence on radar propagation, so that both methods complement each other.In order to be able to combine the NDT-data from several methods records at the same volume, the different data setsmodes of signals must be adapted. The ultrasonic and radar data have to be reconstructed with programs based on the Synthetic Aperture Focusing Technique (SAFT) before data fusion. Subsequently, a conversion of the data into a uniform format has to be carried out. This is a prerequisite in order to keep the data exchange between the project partners as simple as possible. After the data sets are imported and transferred into a common reference system, they can be processed with operations according to the purpose of the investigation. Results, which have been achieved in concrete test specimen with radar and ultrasonics, will be presented and will show the feasibility of the data fusion method. T2 - 6th International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) CY - Berlin, Germany DA - 2003-09-16 KW - Radar KW - Ultrasonic KW - Data Fusion PY - 2003 UR - http://www.ndt.net/article/ndtce03/papers/v023/v023.htm SN - 3-931381-49-8 SP - 1 EP - 11(?) PB - DGZfP CY - Berlin AN - OPUS4-3053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Mayer, K. A1 - Wöstmann, Jens A1 - Wiggenhauser, Herbert T1 - 3D-visualisation of NDT data using a data fusion technique KW - Non-destructive testing KW - Radar KW - Ultrasonic KW - Data fusion KW - SAFT PY - 2003 SN - 0007-1137 VL - 45 IS - 12 SP - 800 EP - 808 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-4585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Krause, Martin A1 - Mielentz, Frank A1 - Milmann, Boris A1 - Mayer, K. T1 - Objektabbildung mit scannenden Ultraschallecho-Verfahren KW - ZfPBau KW - Ultraschallecho KW - Betonbauteile KW - Spannkanäle KW - Phased Array KW - Rekonstruktionsrechnung KW - Modellierung elastischer Wellen PY - 2006 SN - 978-3-433-01833-0 SN - 0342-7617 VL - 1 IS - Kap. V / Abschnitt 8 SP - 543 EP - 554 PB - Ernst CY - Berlin AN - OPUS4-14272 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Milmann, Boris A1 - Schickert, M. A1 - Mayer, K. T1 - Investigation of Tendon Ducts by Means of Ultrasonic Echo Methods - A Comparative Study T2 - 9th European Conference on NDT CY - Berlin, Germany DA - 2006-09-25 KW - NDT-CE KW - Concrete KW - Tendon ducts KW - Ultrasonic echo KW - Ultrasonic imaging KW - Grouting faults PY - 2006 SN - 3-931381-86-2 SP - 1(?) EP - 12(?) PB - European Federation for Non-Destructive Testing CY - Berlin AN - OPUS4-14224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krause, Martin A1 - Mielentz, Frank A1 - Milmann, Boris A1 - Streicher, Doreen A1 - Mayer, K. T1 - Ultrasonic Reflection Properties at Interfaces Between Concrete Steel and Air: Imaging and Modelling T2 - NDE Conference on Civil Engineering CY - St. Louis, Missouri, USA DA - 2006-08-14 KW - Ultrasonic echo KW - Concrete PY - 2006 SN - 1-57117-148-7 SP - 472 EP - 479 PB - ASTM CY - St. Louis AN - OPUS4-14239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, Martin A1 - Mayer, K. A1 - Friese, Martin A1 - Milmann, Boris A1 - Mielentz, Frank A1 - Ballier, G. T1 - Progress in ultrasonic tendon duct imaging N2 - Ultrasonic imaging of tendon ducts enables the precise localisation of grouting faults in many cases. Additionally to well known criteria for detecting grouting faults in tendon ducts recently new possibilities were developed. Two main effects influence the complex behaviour of wave propagation and reflection: a) different arrangement and number of strands or internal rebars; b) superposition of reflecting signals and different wave modes propagating into the interface region around the tendon duct. In order to understand the experimental results, EFIT modelling is performed (EFIT: Elastodynamic Finite Integration Technique). KW - Ultrasonic imaging KW - Prestressed concrete structures KW - Reconstruction calculation KW - SAFT KW - EFIT modelling PY - 2011 DO - https://doi.org/10.3166/ejece.15.461-485 SN - 1964-8189 VL - 15 IS - 4 SP - 461 EP - 485 PB - Lavoisier CY - Paris AN - OPUS4-23853 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mielentz, Frank A1 - Feller, Viktor A1 - Krause, Martin A1 - Orglmeister, R. A1 - Mayer, K. T1 - Schallfeldmodellierung von Ultraschall-Transversalwellen-Prüfköpfen - Modellierung von Prüfkopfarrays mit der Elastodynamischen Finiten Integrationstechnik und der Punktquellensynthese N2 - Ultraschallmessverfahren werden seit Langem erfolgreich für Prüfaufgaben, wie zum Beispiel die Ermittlung von Bauteilgeometrien, im Bauwesen eingesetzt. Um die Schallbündelung der Prüfköpfe zu verbessern, werden oft mehrere Prüfköpfe in einem Array angeordnet. Für die Entwicklung der Prüfkopfarrays ist es zweckmäßig, mithilfe von Modellierungen den Einfluss der Arraygröße, der Anordnung der Einzelprüfköpfe im Array und der Prüffrequenz auf das Schallfeld zu untersuchen. Dazu werden in der Praxis erfolgreich Modellierungen auf der Basis der Elastodynamischen Finiten Integrationstechnik (EFIT) und der Punktquellensynthese angewendet. Beim Aufbau der Arrays kommen zurzeit immer häufiger Transversal-Punktkontaktprüfköpfe zur Anwendung. Daher wird bei der Beschreibung der Schallfeldberechnung insbesondere auf die der Transversalwellenprüfköpfe eingegangen und mithilfe von Modellierungen und Experimenten gezeigt, wie sich die Prüfkopfpositionierung auf die Richtcharakteristik auswirkt. KW - Ultraschall KW - Beton KW - Transversalwellen KW - Modellierung KW - Punktquellensynthese KW - Elastodynamische Finite Integrationstechnik KW - EFIT PY - 2013 DO - https://doi.org/10.3139/120.110510 SN - 0025-5300 VL - 55 IS - 11-12 SP - 856 EP - 864 PB - Hanser CY - München AN - OPUS4-29685 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Jansen, D. A1 - Bald, S. A1 - Birbaum, J. A1 - Küttenbaum, Stefan A1 - Krause, J. A1 - Maack, Stefan A1 - Pichottka, S. A1 - Scherkenbach, M. A1 - Strangfeld, Christoph A1 - Villaret, K. A1 - Wöllenstein, J. T1 - Sensorik zur Substanzbewertung von Straßen N2 - Das vorliegende Arbeitspapier stellt den Stand des Wissens und der Forschung zum Einsatz von Sensorik in Straßenbefestigungen zur Erfassung von Eingangsgrößen und Merkmalen für die Substanzbewertung zusammenfassend dar. Unter Sensorik versteht dieses Arbeitspapier ganz allgemein technische Einrichtungen, mit denen man die Werte von physikalischen Größen erfassen und zur Interpretation darstellen kann. KW - Sensorik KW - Beton KW - Asphalt KW - Messkette KW - Zustandsbewertung PY - 2022 SN - 978-3-86446-314-3 SP - 1 EP - 28 PB - Forschungsgemeinschaft für Straßen- und Verkehrswesen e.V. CY - Köln AN - OPUS4-54530 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krause, Martin A1 - Bärmann, R. A1 - Frielinghaus, R. A1 - Kreschmar, F. A1 - Krogge, O. A1 - Langenberg, K. A1 - Maierhofer, Christiane A1 - Müller, W. A1 - Neisecke, J. A1 - Schickert, M. A1 - Schmitz, V. A1 - Wiggenhauser, Herbert A1 - Wollbold, F. ED - Schickert, G. T1 - Comparison of pulse-echo-methods for testing concrete T2 - International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) CY - Berlin, Germany DA - 1995-09-26 KW - Beton KW - Radar KW - Aufprallecho KW - Ultraschall KW - Prüfung PY - 1995 SN - 3-931381-02-1 N1 - Serientitel: BB / DGZfP – Series title: BB / DGZfP SP - 281 EP - 295 PB - DGZfP, Dt. Ges. für Zerstörungsfreie Prüfung e.V. CY - Berlin AN - OPUS4-593 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weiler, L. A1 - Pfingsten, J. A1 - Eickhoff, H. A1 - Geist, I. A1 - Hilbig, H. A1 - Hornig, U. A1 - Kalbe, Ute A1 - Krause, K. A1 - Kautetzky, D. A1 - Linnemann, V. A1 - Gschwendtner, M. A1 - Lohmann, D. A1 - Overeem-Bos, E. A1 - Schwerd, R. A1 - Vollpracht, A. T1 - Improving consistency at testing cementitious materials in the Dynamic Surface Leaching Test on the basis of the European technical specification CENTS 16637–2 – Results of a round robin test N2 - The environmental impact assessment of materials is usually based on laboratory tests, mostly in combination with models describing the longterm fate of the substances of interest in the targeted environmental compartment. Thus, laboratory tests are the fundamental link to achieve appropriate assessment conclusions which makes it essential to generate consistent results. This just as applies to the leaching of cementitious materials. In Europe, the leaching behavior of monolithic building materials is tested in the Dynamic Surface Leaching Test following the specification CEN/TS 16637–2. An interlaboratory comparison on European level regarding this technical specification showed relatively high intra- and interlaboratory variations for the tested materials (monolithic copper slag and cement stabilized coal fly ash). Therefore the German Committee for Structural Concrete (DAfStb) framed a guideline to specify additional testing conditions for cementitious materials. To assess the possible improvement by this guidelines measures, a round robin test with 11 participants from Germany and the Netherlands was conducted. This work aims to provide insight into the factors to be considered in the testing of alkaline materials, including sample preparation, and highlights crucial procedures and their manifestation in the results. All evaluated parameters showed improved results compared to the earlier round robin test. The relative standard deviations for repeatability (RSDr) and reproducibility (RSDR) of the elements calcium, barium, antimony, chromium, molybdenum and vanadium, which are the parameters evaluated in both round robin tests, were RSDr = 4%, 4%, 2%, 5%, 5%, and 5% respectively (4% in average) for this work, in comparison to the European round robin test with an average RSDr of 29% (17%, 17%, 20%, 40%, 36%, and 42%). The RSDR improved from 41% (30%, 36%, 29%, 57%, 40%, and 56%) to 14% (12%, 8%, 6%, 28%, 15%, and 12%). CO2 ingress during testing and the inaccuracy of eluate analytics for concentrations close to the determination limits were identified as the main sources of error. KW - Environmental assessment KW - Leaching KW - Heavy metals KW - Round robin test KW - Building Material PY - 2022 DO - https://doi.org/10.1016/j.jenvman.2022.114959 SN - 0301-4797 VL - 314 SP - 1 EP - 9 PB - Elsevier CY - Amsterdam AN - OPUS4-54647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yildirim, Arda A1 - Bühlmeyer, A. A1 - Hayash, S A1 - Haenle, J. C. A1 - Sentker, K. A1 - Krause, Christina A1 - Huber, Patrick A1 - Laschat, Sabine A1 - Schönhals, Andreas T1 - Multiple glassy dynamics in dipole functionalized triphenylene-based discotic liquid crystals revealed by broadband dielectric spectroscopy and advanced calorimetry – assessment of the molecular origin N2 - A selected series of dipole functionalized triphenylene-based discotic liquid crystals (DLCs) was synthesized and investigated in a systematic way to reveal the phase behavior and molecular dynamics. The later point is of particular importance to understand the charge transport in such systems which is the key property for their applications such as organic field-effect transistors, solar cells or as nanowires in molecular electronics, and also to tune the properties of DLCs. The mesomorphic properties were studied by polarizing optical microscopy, X-ray diffraction, and differential scanning calorimetry, which were compared to the corresponding unfunctionalized DLC. The molecular dynamics were investigated by a combination of state-of-the-art broadband dielectric spectroscopy (BDS) and advanced calorimetry such as fast scanning calorimetry (FSC) and specific heat spectroscopy (SHS). Besides localized fluctuations, surprisingly multiple glassy dynamics were detected for all materials for the first time. Glassy dynamics were proven for both processes unambiguously due to the extraordinary broad frequency range covered. The a1-process is attributed to fluctuations of the alky chains in the intercolumnar space because a polyethylene-like glassy dynamics is observed. This corresponds to a glass transition in a confined three-dimensional space. The a2-process found at temperatures lower than a1-process, is assigned to small scale rotational and/or translational in plane fluctuations of the triphenylene core inside distorted columns. This can be considered as a glass transition in a one-dimensional fluid. Therefore, obtained results are of general importance to understand the glass transition, which is an unsolved problem of condensed matter science. KW - Discotic Liquid Crystals KW - Broadband dielectric spectroscopy KW - Flash DSC KW - Specific heat spectroscopy PY - 2019 DO - https://doi.org/10.1039/c9cp03499d SN - 1463-9076 VL - 21 IS - 33 SP - 18265 EP - 18277 PB - RSC AN - OPUS4-48739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Krause, Martin A1 - Schubert, Marcus A1 - Mayer, K. A1 - Ibrahim, M. T1 - Sicherstellung der Ausführungsqualität an Neu- und Bestandsbauten aus Beton durch innovative zerstörungsfreie Prüfung N2 - Der Fachbereich 8.2 der Bundesanstalt für Materialforschung und -prüfung (BAM) hat eine innovative Methode zur zerstörungsfreien Ultraschallprüfung erarbeitet und den technischen Aufbau in Form eines neuen Gerätes entwickelt. Mit Hilfe des Produktdesigns soll die Etablierung auf dem Markt sichergestellt werden. Die Arbeit erläutert detailliert die Bereiche, die für die Gestaltung des Handscangerätes von Bedeutung sind. Sie befasst sich mit der Installation und Handhabung des Systems am Einsatzort und beleuchtet wichtige technische Details. Der nicht verkleidete technische Aufbau der zwei neu entwickelten Geräte dient als Grundlage für die Erarbeitung eines Gehäusekonzepts. Neben dem Gehäusedesign wird eine Überarbeitung des gesamten Aufbaus durchgeführt, um die Benutzerfreundlichkeit in verschiedenen Punkten zu verbessern. Zukünftige Designentscheidungen werden auf Grundlage von praxisnahen Beobachtungen und der notwendigen Anordnung der technischen Komponenten getroffen. Ziel der Auseinandersetzung ist es, ein funktionelles und ästhetisch ansprechendes Design zu entwickeln. Am Ende sollen unter Beachtung aller Vorgaben die Ergebnisse dieser Arbeit zu einem ergonomischen Gerät führen. Die Problemstellung besteht daraus, den komplexen technischen Vorgaben und Ansprüchen des Projektpartners und Innovationsgebers gerecht zu werden und gleichzeitig ein gutes Designziel zu erreichen. Das Design soll die Funktionalität und Handhabung des Gerätes verbessern und dient als Hilfsmittel, um den komplexen Aufbau zu vereinfachen. Die Benutzerfreundlichkeit soll an allen nötigen Stellen verbessert werden und ein ästhetisch zusammenstehender Gesamteindruck soll entstehen, ohne die Funktionalität negativ zu beeinflussen. KW - Beton KW - Qualitätssicherung KW - Zerstörungsfreie Prüfung KW - Ultraschall-Echo PY - 2018 UR - https://www.baufachinformation.de/sicherstellung-der-ausfuehrungsqualitaet-an-neu-und-bestandsbauten-aus-beton-durch-innovative-zerstoerungsfreie-pruefung/buecher/248990 SN - 978-3-7388-0101-9 VL - 2018 SP - 1 EP - 112 PB - Fraunhofer IRB Verlag CY - Stuttgart AN - OPUS4-45163 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sieg, H. A1 - Braeuning, C. A1 - Kunz, B. M. A1 - Daher, H. A1 - Kästner, C. A1 - Krause, B.-C. A1 - Meyer, T. A1 - Jalili, P. A1 - Kogeveen, K. A1 - Böhmert, L. A1 - Lichtenstein, D. A1 - Burel, A. A1 - Chevance, S. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Laux, P. A1 - Braeuning, A. A1 - Gauffre, F. A1 - Fessard, V. A1 - Meijer, J. A1 - Estrela-Lopis, I. A1 - Thünemann, Andreas A1 - Luch, A. A1 - Lampen, A. T1 - Uptake and molecular impact of aluminum-containing nanomaterials on human intestinal caco-2 cells N2 - Aluminum (Al) is one of the most common elements in the earth crust and increasingly used in food, consumer products and packaging. Its hazard potential for humans is still not completely understood. Besides the metallic form, Al also exists as mineral, including the insoluble oxide, and in soluble ionic forms. Representatives of these three species, namely a metallic and an oxidic species of Al-containing nanoparticles and soluble aluminum chloride, were applied to human intestinal cell lines as models for the intestinal barrier. We characterized physicochemical particle parameters, protein corona composition, ion release and cellular uptake. Different in vitro assays were performed to determine potential effects and molecular modes of Action related to the individual chemical species. For a deeper insight into signaling processes, microarray transcriptome analyses followed by bioinformatic data analysis were employed. The particulate Al species showed different solubility in biological media. Metallic Al nanoparticles released more ions than Al2O3 nanoparticles, while AlCl3 showed a mixture of dissolved and agglomerated particulate entities in biological media. The protein corona composition differed between both nanoparticle species. Cellular uptake, investigated in transwell experiments, occurred predominantly in particulate form, whereas ionic Al was not taken up by intestinal cell lines. Transcellular transport was not observed. None of the Al species showed cytotoxic effects up to 200 mg Al/mL. The transcriptome analysis indicated mainly effects on oxidative stress pathways, xenobiotic metabolism and metal homeostasis. We have shown for the first time that intestinal cellular uptake of Al occurs preferably in the particle form, while toxicological effects appear to be ion-related. KW - Small-angle x-ray scattering KW - SAXS KW - Nanopatricle PY - 2018 DO - https://doi.org/10.1080/17435390.2018.1504999 SN - 1743-5390 VL - 12 IS - 9 SP - 992 EP - 1013 PB - Taylor & Francis AN - OPUS4-47432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayer, K. A1 - Krause, Martin A1 - Ibrahim, M. A1 - Schubert, Marcus T1 - Requirements for a Small Size Ultrasonic Imaging System for Inspection of Concrete Elements N2 - Ultrasonic imaging systems usually require an array of ultrasonic transducers for data acquisition on a wide area on top of an object under investigation. The goal of an imaging algorithm is the use of reflected ultrasound data to form a recognizable image. Conventional algorithms like SAFT are based on an inverse Huygens' principle and need therefore a dense measurement grid. This requires a big effort in data capturing. For simple and inexpensive measurement different strategies of imaging with reduced amount of data and examples with a manual scanning device on concrete elements are presented. T2 - 19th World Conference on Non-Destructive Testing 2016 CY - Munich, Germany DA - 13.06.2016 KW - NDT-CE KW - Ultrasonic echo KW - SAFT PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-388548 SP - 1245 EP - 1254 PB - DGZfP CY - Bad Breising, Germany AN - OPUS4-38854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayer, K. A1 - Krause, Martin A1 - Wiggenhauser, Herbert A1 - Milmann, Boris T1 - Investigations for the improvement of SAFT imaging quality of a large aperture ultrasonic system N2 - In parallel to the hardware development of an ultrasonic system for the investigation of thick concrete structures, a software package for interactive reconstruction of data for that special arrangement of ultrasonic transducers was developed. The system which is presented in a further contribution to this conference as "large aperture ultrasonic system" (LAUS) requires special features to the evaluation software because measuring positions can be in a non equidistant grid and there is the possibility to improve the measurement by adding measuring points interactively. Starting from theoretical considerations to the image generation by measuring arrangements of synthetic aperture problems, solution approaches for imaging with SAFT (Synthetic Aperture Focusing Technique) algorithms in space and frequency domain of data from insufficient grid density are presented. A wide range of issues that may arise in the application is precalculated by simulations and experimental studies, so that unavoidable artifacts can be identified and classified. A special focus is put on the application of thick concrete structures considering missing measuring points in a grid, grating lobes and surface waves. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 KW - Ultraschallecho-Verfahren KW - Betonbauteile KW - Grating lobe reduction KW - Linear array KW - Synthetic aperture focusing technique (SAFT), KW - Ultrasound imaging PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-346421 SN - 1435-4934 SP - 1026 EP - 1034 PB - Technische Universität Berlin / Bundesanstalt für Materialforschung und -prüfung AN - OPUS4-34642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Wagner, Patrick A1 - Rappsilber, Tim A1 - Liebner, Christian A1 - Hahn, S.-K. A1 - Krause, U. T1 - Harmful effects of lithium-ion battery thermal runaway: scale-up tests from cell to second-life modules N2 - For a comprehensive safety assessment of stationary lithium-ion-battery applications, it is necessary to better understand the consequences of thermal runaway (TR). In this study, experimental tests comprising twelve TR experiments including four single-cell tests, two cell stack tests and six second-life module tests (2.65 kW h and 6.85 kW h) with an NMC-cathode under similar initial conditions were conducted. The temperature (direct at cells/modules and in near field), mass loss, cell/module voltage, and qualitative vent gas composition (Fourier transform infrared (FTIR) and diode laser spectroscopy (DLS) for HF) were measured. The results of the tests showed that the battery TR is accompanied by severe and in some cases violent chemical reactions. In most cases, TR was not accompanied by pregassing of the modules. Jet flames up to a length of 5 m and fragment throwing to distances to more than 30 m were detected. The TR of the tested modules was accompanied by significant mass loss of up to 82%. The maximum HF concentration measured was 76 ppm, whereby the measured HF concentrations in the module tests were not necessarily higher than that in the cell stack tests. Subsequently, an explosion of the released vent gas occurred in one of the tests, resulting in the intensification of the negative consequences. According to the evaluation of the gas measurements with regard to toxicity base on the “Acute Exposure Guideline Levels” (AEGL), there is some concern with regards to CO, which may be equally as important to consider as the release of HF. KW - Large-scale tests KW - Lithium-ion battery KW - Gas emission KW - Thermal runaway KW - Consequences PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579054 DO - https://doi.org/10.1039/D3RA02881J SN - 2046-2069 VL - 13 IS - 30 SP - 20761 EP - 20779 PB - Royal Society of Chemistry (RSC) CY - Cambridge, UK AN - OPUS4-57905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Krause, Ulrich T1 - BEV Accidents - Consequences in Case of a Battery Thermal Runaway N2 - The number of cars which use a battery for propulsion, like BEV (battery electric vehicle) or PHEV (plug-in hybrid electric vehicle), is increasing. Following, the probability of these car types being involved in car accidents will increase. In a worst-case accident scenario, the installed batteries could go under thermal runaway (TR). A TR could be initiated by various causes, e.g., high temperatures from outside, mechanical damage of the cells/modules/batteries or internal and external short circuits. During such an event, large amounts of heat and toxic and/or flammable gases are released. This poses a great hazard to people and property in the immediate vicinity. The paper describes a large-scale test series on the lithium-ion battery TR consequences of automobile cells and modules up to E = 6.85 kWh. Near field temperatures of ΔT > 800°C in a distance of l = 2 m were measured. During an overcharge test, fragment throwing distances of l > 30 m were detected. Subsequent gas explosions of the released gases were documented. Hydrogen fluoride (HF) was measured in all tests, from cell to module. The highestmeasured concentration was cHF = 76 ppm, which is significantly higher than the 30-min-level for AEGL 2 (acute exposure guideline level 2). Based on the experimentally determined consequences, concrete measures for the accident analysis are subsequently drawn. T2 - 31st Annual Congress of the European Association for Accident Research and Analysis (EVU) CY - Limassol, Cyprus DA - 05.10.2023 KW - Gas release KW - Consequences KW - Lithium-ion battery KW - Electrical Energy Storage KW - BEV PY - 2023 SP - 1 EP - 18 AN - OPUS4-58552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Saupe, Alexander A1 - Janßen, Marvin A1 - Krause, Ulrich T1 - Sicherheitsrisiko Batterien – Demonstrator aus dem Projekt SEE-2L bereits im Einsatz N2 - Der Beitrag beschreibt das BMBF-Verbundvorhaben SEE-2L. Im Artikel werden die wesentlichen Meilensteine des Projektes vorgestellt. Ebenso werden die wichtigsten im Projekt erzielten Ergebnisse aufgeführt und verlinkt. KW - Stationäre Energiespeicher KW - Batterie KW - Auswirkungsbetrachtungen KW - EES KW - Elektrische Energiespeicher PY - 2023 UR - https://info.sifo.de/public/a_25436_GZ5jd/file/data/669_Informationsbrief_zur_zivilen_Sicherheitsforschung_07-2023.pdf#page=7 IS - 7 SP - 7 EP - 9 PB - Bundesministerium für Bildung und Forschung (BMBF) CY - Bonn AN - OPUS4-58347 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Krause, Ulrich T1 - BMBF-Vorhaben SEE-2L - Auswirkungen des thermischen Durchgehens von Second-Life-Lithium-Ionen-Batterien auf Modulebene N2 - Elektrische Energiespeicher können unter bestimmten Bedingungen thermisch Durchgehen. Dies ist mit der Freisetzung von großen Mengen an Wärme sowie toxischen und/oder brennbaren Gasen assoziiert. Um die potenziellen Auswirkungen des thermischen Durchgehens zu quantifizieren, wurden Versuche mit Zellen und Modulen mit einem Energieinhalt von bis zu E = 6,85 kWh durchgeführt. Es wurden verschiedene Kenngrößen, wie z.B. Temperatur, Spannung, Massenabbrand, qualitative Gaszusammensetzung sowie Fragmente, messtechnisch erfasst und ausgewertet. Die Ergebnisse können sowohl für Bemessungen im vorbeugenden baulichen Brandschutz als auch in der Prozess- und Anlagensicherheit verwendet werden. Ebenso können sie in Konzept des abwehrenden Brandschutzes integriert werden. KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 SN - 1868-6540 VL - 73. Jahrgang IS - 3 SP - 111 EP - 122 PB - Ebner Media Group GmbH & Co. KG CY - Ulm AN - OPUS4-61082 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. A1 - Tschirschwitz, Rico A1 - Amano, Kofi Owusu Ansah A1 - Gimadieva, Elena A1 - Krause, Ulrich T1 - A Study on Thermal Runaway Propagation in Battery Modules Assembled from Pouch Cells N2 - Thermal runaway reactions were studied in arrangements from single battery cells with energy capacities of 2.5 Ah (9.25 Wh) to battery modules up to 6.85 kWh. All cells were pouch cells of the Li-ion NMC type and the modules were composed of such. Abuse was triggered either by overcharging or thermally by attaching a heat source (heating plate or glow plug) to the cells. Experiments with single cells or assemblies of two to four cells were undertaken in closed autoclaves. Samples of the gas released from the cells during the runaway were extracted and analysed using a Fourier-transformed infrared spectrometer (FTIR). In some experiments pressure peaks up to 7 bar (g) were observed which could not be explained by the gas release alone. Obviously, secondary explosions took place. Thermal runaway propagation was studied with and without an insulation layer between the battery cells. Several materials and combinations of them were tested as insulations: hollow glass spheres (Pyrobubbles®), phase change materials (PCM) and intumescent materials. Experiments showed that already layers of 10 to 20 mm of insulation effectively prevented the propagation of a thermal runaway. In addition to the experiments, a mathematical model was developed for studying numerically the heat transfer through arrangements of multiple battery cells and also the effect of insulation layers. This model was implemented into the commercial finite-element software package COMSOL Multiphysics®. The simulations confirmed the experimental findings that already quite thin insulation layers between cells or modules effectively delay or even suppress the propagation of the thermal runaway. T2 - EUSAS conference "Addressing the Fire Risks of Electromobility" CY - Frankfurt am Main, Germany DA - 10.05.2023 KW - Thermal Runaway KW - Consequences KW - Electrical Energy Storage KW - Gas release KW - Lithium-ion battery PY - 2024 UR - https://eusas.eu/publications/eusas-journals VL - 15 SP - 43 EP - 50 PB - EUSAS e.V. (European Society for Automatic Alarm Systems e.V.), Universität Duisburg-Essen, Dept. Nachrichtentechnische Systeme CY - Duisburg AN - OPUS4-61598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. A1 - Saupe, Alexander A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Janßen, Marvin A1 - Amano, Kofi Owusu Ansah A1 - Krause, Ulrich T1 - Sicherheit elektrochemischer Energiespeicher – Ergebnisse aus dem Projekt SEE-2L N2 - Die Transformation der Energienutzung von konventionellen zu erneuerbaren Quellen führt dazu, dass zukünftig mehr Energie effizient zwischengespeichert werden muss. Eine Möglichkeit der elektrochemischen Zwischenspeicherung bieten Lithium-Ionen-Batterien. Hierfür können ausgemusterte Automobilantriebsbatterien verwendet werden. Erfüllen sie die hohen Anforderungen des mobilen Bereichs nicht mehr, haben sie oftmals noch eine ausreichende Kapazität und Leistungsfähigkeit für die stationäre Zwischenspeicherung. Neben der Verwendung der Batterien im größeren Maßstab, z.B. bei Energieversorgern, werden durch den vermehrten Einsatz von Photovoltaik-Anlagen in Ein- und Mehrfamilienhäusern verstärkt Zwischenspeicher für Privathaushalte nachgefragt. Dies birgt auch für Einsatzkräfte neue Herausforderungen in der Gefahrenabwehr. Im vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Verbundprojekt „SEE-2L – Sicherheit elektrochemischer Energiespeicher in Second Life Anwendungen“ wurden Versuche mit Second Life Modulen durchgeführt. Verbundpartner im Projekt waren neben der vfdb die Otto-von-Guericke-Universität Magdeburg und die Bundesanstalt für Materialforschung und -prüfung. Zudem war das Institut der Feuerwehr Nordrhein-Westfalen eingebunden. Die durchgeführten Versuche bilden eine Grundlage für die Einordnung der Batteriespeicher, z.B. aus Sicht des baulichen Brandschutzes, zur Methodik der Brandbekämpfung oder zur Risikobewertung hinsichtlich der Prozess- und Anlagensicherheit. Im Beitrag werden die Versuchsergebnisse vorgestellt und Ansätze für deren Anwendung gezeigt. Um die gewonnenen Erkenntnisse zu vermitteln, wurde im Projekt zudem ein Schulungskonzept für Einsätze mit Lithium-Ionen-Technologien erarbeitet, das im Beitrag präsentiert wird. Es besteht aus theoretischen und praktischen Anteilen, sodass bei den Feuerwehren praxisnah aus- bzw. fortgebildet werden kann. T2 - 70. Jahresfachtagung der vfdb CY - Magdeburg, Deutschland DA - 06.05.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 SN - 978-3-9360-5038-7 SP - 645 EP - 657 PB - vfdb, Vereinigung zur Förderung des Deutschen Brandschutzes e.V. CY - Münster AN - OPUS4-60068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kusche, Christian A1 - Knaust, Christian A1 - Hahn, S.-K. A1 - Krause, U. T1 - Experimental investigations of the combustion efficiency for fire load calculations T1 - Experimetelle Untersuchungen der Verbrennungseffektivität für Brandlastberechnungen N2 - The amount of heat, which is released by fire loads during the combustion process, depends on the material characteristics, the ventilation conditions, the storage density and the distribution. To evaluate the structural stability of buildings in case of fire, the fire load has to be quantified. In Germany, the fire load is quantified by using the combustion factor m, while internationally the combustion efficiency χ is applied. Both factors assess the burning behavior of materials, but the determination is carried out in different ways. Since the testing facility was abolished fifteen years ago, it is not possible to determine the combustion factor m anymore. So, it should be found out, if the combustion efficiency χ is a convenient method to quantify the fire load under the consideration of the German standards. As a part of the research, combustion efficiencies χ were determined for eight materials in the cone calorimeter and the single burning item test at different heat fluxes. The values of the combustion efficiencies χ as well as the corresponding combustion factors m were discussed and compared to the values of the literature. The results show an influence of the testing facility on the combustion efficiency. The values of the combustion efficiency determined in the single burning item test were higher than the values from the cone calorimeter. N2 - Die Wärmefreisetzung einer Brandlast im Brandfall hängt von den Materialeigenschaften, den Ventilationsbedingungen, der Lagerungsdichte und der Verteilung im Brandraum ab. Die Festlegung der erforderlichen Feuerwiderstandsdauer in industriellen Gebäuden erfolgt auf Basis der Brandlast. In Deutschland dient der Abbrandfaktor m (m-Faktor) zur Berechnung der Brandlast, wohingegen international die Verbrennungseffektivität χ zur Berechnung verwendet wird. Zwar charakterisieren beide Faktoren das Abbrandverhalten von Stoffen, jedoch sind ihre Bestimmungsmethoden unterschiedlich. Seit der Abschaffung des letzten m-Faktor-Ofens vor mehr als 15 Jahren, ist die Bestimmung von m-Faktoren nicht mehr möglich. Daher soll untersucht werden, ob die Verbrennungseffektivität χ an Stelle des m-Faktors zur Berechnung der Brandlast im Rahmen deutscher Normen verwendet werden kann. Für diese Untersuchungen wurde die Verbrennungseffektivität χ von acht Stoffen im Cone Calorimeter und im Single Burning Item Test bei unterschiedlichen Wärmestromdichten bestimmt. Die ermittelten Werte der Verbrennungseffektivität χ wurden den bestehenden m-Faktoren gegenübergestellt und mit Werten aus der Literatur verglichen. Die Untersuchungen haben ergeben, dass die Prüfapparaturen zu unterschiedlichen Verbrennungseffektivitäten führen. Die Werte aus der Messung des SBI waren höher als die des Cone Calorimeters KW - Combustion efficiency KW - Combustion factor KW - Fire load density KW - Cone calorimeter KW - Single burning item test PY - 2015 DO - https://doi.org/10.3139/120.110795 SN - 0025-5300 VL - 57 IS - 10 SP - 843 EP - 849 PB - Carl Hanser Verlag CY - München AN - OPUS4-38738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiggenhauser, Herbert A1 - Samokrutov, A A1 - Mayer, K A1 - Krause, Martin A1 - Alekhin, S. G. A1 - Elkin, V T1 - Large aperture ultrasonic system for testing thick concrete structures N2 - A Large Aperture UltraSonic system (LAUS) has been designed and built for testing thick concrete structures. The scalable system consists of twelve ultrasonic units, each hosting 32 individual shear wave transducers with mechanical dry point contact (DPC) to the concrete surface. The twelve units are attached to the concrete surface using a vacuum case which holds them in place during operation. Each LAUS unit can be placed individually on the surface to achieve optimal ultrasonic condition, e.g. to avoid rebars. For the generation of vacuum, air pressure is supplied to each unit through an air hose. The twelve units define an aperture which is necessary for fast reconstruction of the subsurface structure. The well-known SAFT (Synthetic Aperture Focusing Technique) algorithm has been adopted to this situation, where the individual LAUS units form a linear aperture with not necessarily equidistant spacing between the units. The exact geometrical position of the units, which are individually marked with retroreflective labels, is determined using photographs and image processing. All transducers are synchronized and work either as transmitter or receiver. A full scan consists of 12 * 11 recordings, where each unit acts as transmitter once and all others as receivers. An electronic sub-unit on the back of the ultrasonic device holds the battery and handles data acquisition, synchronization and data communication. A computer is used as base unit which communicates with each LAUS unit for control and data acquisition, the synchronization is performed by a radio modem that uses a special algorithm similar to a digital PLL (phase locked loop). No wire connections are necessary between the units and the base system. The LAUS system is designed to investigate concrete structures with thicknesses in excess of 2 m, depending on the acoustic condition of the object under investigation. Highly reinforced concrete may have less penetration depth. The LAUS provides quasi real time imaging, once the transducers are put in place and the data has been acquired. First measurements on a foundation slab confirm, that the system can register ultrasonic echoes from the back wall at 4 m distance. KW - Ultrasound "Large Aperture" NDT Concrete PY - 2017 DO - https://doi.org/10.1061/(ASCE)IS.1943-555X.0000314 SN - 1076-0342 SN - 1943-555X VL - 23 IS - 1 SP - B4016004-1 EP - B4016004-9 PB - American Society of Civil Engineers (ASCE) CY - Reston, VA 20191-4400 USA AN - OPUS4-39372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, S.-K. A1 - Rost, M. A1 - Kusche, Christian A1 - Knaust, Christian A1 - Krause, U. T1 - Dokumentation der Entwicklung des m-Faktors und neuer Aspekt der Verbrennungseffizienz T1 - Structural fire protection in industrial buildings - development of the m-factor and new aspect of the combustion efficiency N2 - Vor dem Hintergrund der Zurückziehung der DIN 18230 Teil 2 zur Bestimmung des m-Faktors von Materialien für die Brandlastbewertung im Industriebau müssen neue Wege gefunden werden, wie das Abbrandverhalten alternativ quantifiziert werden kann. Der Beitrag fasst die Entstehung und die Entwicklung der Bestimmungsweise von Abbrandfaktoren zusammen und gibt Ausblick auf eine neue Möglichkeit zur Bewertung von Brandlasten, die Verbrennungseffizienz. KW - Abbrandfaktor KW - DIN 18230 KW - Indrustriebau KW - Brandschutz im Brandlast KW - Verbrennungseffizienz PY - 2017 DO - https://doi.org/10.1002/bate.201700020 SN - 0932-8351 SN - 1437-0999 VL - 94 IS - 6 SP - 337 EP - 343 PB - Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin AN - OPUS4-40962 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kroggel, O. A1 - Krause, Martin A1 - Schickert, M. A1 - Langenberg, K.-J. T1 - Moderne Verfahren der Bauwerksdiagnose, Entwicklung und Anwendung - Die DFG-Forschergruppe FOR384 stellt ihre Ergebnisse vor - Ultraschall T2 - Fachtagung 2005 des Deutschen Ausschusses für Stahlbeton in Zusammenarbeit mit der Bundesanstalt für Materialforschung und -prüfung "Zerstörungsfreie Prüfverfahren und Bauwerksdiagnose im Betonbau" CY - Berlin, Deutschland DA - 2005-03-10 KW - Ultraschallecho-Verfahren KW - Beton KW - Fundamente KW - Erhärtungsverhalten KW - Tomographie PY - 2005 SP - A5 EP - A10 PB - BAM CY - Berlin AN - OPUS4-11718 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, Sarah-K. A1 - Tschirschwitz, Rico A1 - Pascal, Schmitz A1 - Krause, Ulrich T1 - Forschung zur Sicherheit von Elektroenergiespeichern N2 - Bei der Umstellung der Energieversorgung von fossilen auf „erneuerbare“ Energieträger kommt der Zwischenspeicherung von Energie eine entscheidende Bedeutung zu. Volatile Energieträger wie Solar- und Windenergie werden in Abhängigkeit der Tageszeit und des Wetters gewonnen, sodass die Energiegewinnung starken Schwankungen unterliegt und gleichzeitig begrenzt vorhersagbar ist. Hinzu kommt, dass der Zeitpunkt von Spitzenwerten verfügbarer Energie (z. B. Sommernachmittag bei Wind und Sonnenschein) nur bedingt mit den Zeiten des größten Energiebedarfs (z. B. Winterabend mit niedrigen Temperaturen) übereinstimmt. KW - Auswirkungsbetrachtungen KW - Thermisches Durchgehen KW - Stationäre Energiespeicher KW - Lithium-Ionen-Batterie KW - Elektrische Energiespeicher PY - 2025 UR - https://www.schadenprisma.de/archiv/artikel/forschung-zur-sicherheit-von-elektroenergiespeichern/ SN - 0343-3560 VL - 2025 IS - 2 SP - 14 EP - 17 PB - Institut für Schadenverhütung und Schadenforschung der öffentlichen Versicherer e.V. (IFS) CY - Kiel AN - OPUS4-63994 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, Sarah‐K. A1 - Gnutzmann, Tanja A1 - Meinert, Marion A1 - Hofmann-Böllinghaus, Anja A1 - Oberhagemann, Dirk A1 - Krause, Ulrich T1 - Incipient Fires—Definition, Detection and Extinguishment by Laypersons N2 - The earlier a fire is noticed, the less developed it is and the easier it can be prevented respectively stopped, even by laypersons. Within the research project ‘TEBRAS’ the incipient phase of fires was investigated in detail. In the course of the project, it became apparent that the definition of what exactly the incipient phase of a fire encompasses is not definite and depends on the disciplines dealing with the subject ‘fire’. Based on the results of a literature review, an inquiry under experts and laypersons as well as practical fire tests a definition for the phenomenon of the incipient fire was developed which divides it into four phases. Driving key factors for each phase are identified considering the main parameters to detect and extinguish the fire. KW - Developing fires KW - Development of fires PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-649310 DO - https://doi.org/10.1002/fam.70025 SN - 0308-0501 VL - 50 IS - 1 SP - 3 EP - 10 PB - Wiley AN - OPUS4-64931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -