TY - GEN A1 - Meng, Birgit A1 - Fontana, Patrick A1 - Müller, Urs ED - Stephan, D. T1 - Nano-Gefügeanalytik als Optimierungsgrundlage für innovative Baustoffe - am Beispiel zementgebundener Baustoffe KW - Nanotechnologie KW - Analytik KW - Gefüge KW - Zement KW - Beton PY - 2007 SN - 3-89958-348-9 IS - 8 SP - 36 EP - 49 PB - Kassel University Press GmbH CY - Kassel AN - OPUS4-16363 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Sebastian A1 - Selleng, C. A1 - von Werder, Julia A1 - Meng, Birgit T1 - Einfluss der thermischen Behandlung auf die Phasenentwicklung und die Eigenschaften von UHPC N2 - UHPC (engl. ultra-high-performance concrete) bietet außergewöhnliche Eigenschaften, die sich durch eine optimierte Wärmebehandlung weiter verbessern lassen. Wie bei normalen Beton beschleunigt eine Wärmebehandlung den Aushärteprozess und reduziert das Schrumpfen. Durch Ausbildung eines dichteren Gefüges wird weiterhin die Druckfestigkeit und die Resistenz gegenüber Umwelteinflüssen erhöht. Die Art der Wärmebehandlung wird durch die Parameter: Temperatur, Druck, Wasserdampfsättigung und Dauer definiert und hat einen entscheiden Einfluss auf die Phasenentwicklung und damit auf die makro- und mikroskopischen Eigenschaften des UHPCs. Auch die Dauer und Art der Vorlagerung des UHPCs vor der thermischen Behandlung sind von Bedeutung. Ziel der vorgestellten Untersuchung war der Vergleich und die Optimierung verschiedener Wärmebehandlungsarten mit Blick auf die Druckfestigkeits- und Phasenentwicklung. Dafür wurden UHPC-Zylinder und Prismen hergestellt und ungeschützt bzw. in Folie eingeschweißt bei 90 °C im Ofen, im Heißwasserbad, sowie alternativ bei 185 °C und 1.1 MPa im Autoklaven wärmebehandelt. Zusätzlich wurde die Vorlagerungs- und die Behandlungszeit systematisch variiert. Die Ergebnisse zeigen, dass eine praxisnahe Wärmebehandlung im Ofen (kurze Vorlagerungs- und Behandlungszeit, Verdunstungsschutz durch Einschweißen in Folie) zwar zu einer stark erhöhten Frühfestigkeit führt, aber die Langzeitfestigkeit wird nicht signifikant erhöht. Erst längere Behandlungszeiten verbunden mit intensiviertem Schutz gegen das Austrocknen führen darüber hinaus zu deutlich erhöhten Langzeitfestigkeiten. Nach der Autoklavierung dagegen wurden Festigkeitszuwächse von bis zu 30 % gemessen. Die röntgenographisch nachgewiesene Phasenentwicklung wird in beiden Behandlungsarten durch die Limitierung des zur Verfügung stehenden Wassers bestimmt. Bei der Wärmebehandlung im Ofen wird das durch den Ettringitzerfall freigesetzte Wasser für die puzzolanische Reaktion der Mikrosilika verbraucht, reicht aber für eine weitere Reaktion der Klinkerphasen nicht aus. Bei der hydrothermalen Behandlung dagegen zeigen die Veränderungen im Phasenbestand sowohl eine Intensivierung der puzzolanischen als auch der hydraulischen Reaktion. Der für autoklavierte Baustoffe charakteristische Tobermorit konnte jedoch nicht im Probeninneren, sondern nur als Belag auf der Probenoberfläche nachgewiesen werden. Ursächlich hierfür ist vermutlich wiederum das zu geringe Wasserangebot im Gefüge des UHPC. T2 - 20. Internationale Baustofftagung ibausil CY - Weimar, Germany DA - 12.09.2018 KW - UHPC KW - Wärmebehandlung KW - Hydrothermale Behandlung KW - XRD KW - Kristalline CSH-Phase KW - Tobermorit KW - Ettringit KW - Hydroxyellestadit KW - Hydrogranat PY - 2018 SN - 978-3-00-059950-7 SP - 1 EP - 10 AN - OPUS4-46176 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Simon, Sebastian A1 - Lehmann, C. A1 - Selleng, C. A1 - Fontana, P. A1 - Meng, Birgit T1 - Autoclaving of ultra-high performance concrete (UHPC) N2 - By the combination of an optimized granulometry, a reduced water cement ratio and the use of superplasticizers ultra-high performance concrete achieves a compressive strength of over 150 N/mm2 and a high resistance regarding acids and water-soluble salts. In different Research projects the effect of an autoclavation on the mechanical strength and the phase composition was analyzed. In systematic studies, the concrete mix and the process parameters were varied. The results show that autoclavation leads to an improved pozzolanic and hydraulic reaction and significantly improves the mechanical strength compared to a conventional thermal treatment. If a minimum time-span for hydration is ensured, the achievable strength level is not dependent on the prestorage time. However, the duration of the autoclaving is significant. After the Maximum strength is reached there is only a very slight decrease, even if unrealistically long autoclaving times are applied. T2 - ICAAC 6th International Conference on Autoclaved Aerated Concrete CY - Potsdam, Germany DA - 04.09.2018 KW - Heat treatment KW - Hydroxylellestadite KW - Tobermorite KW - Ultra-high performance concrete KW - Zonation PY - 2018 SN - 978-3-433-03276-3 DO - https://doi.org/10.1002/cepa.866 SP - 131 EP - 136 PB - Wilhelm Ernst & Sohn - Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin, Germanry AN - OPUS4-46357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Sebastian A1 - Selleng, C. A1 - Meng, Birgit T1 - Prompt phase analyses of ultrahigh-performance concrete N2 - Powder X-ray diffraction is a time-consuming and challenging task, especially for preparation of sensitive phases like ettringite and calcium-silicate-hydrate (C-S-H) phases. Fine-grained ultrahigh-performance concrete (UHPC) with an average grain size <100 μm could be investigated directly without time-consuming milling. As a proof of concept, small UHPC cylinders with plain surfaces were investigated with a newly designed sample holder. The comparison with conventionally prepared powder shows the feasibility of fast qualitative phase analysis using this approach. As a great benefit, a depth-dependent analysis, as well as a comparison of surface layers and core material, was carried out. KW - Ultrahigh-performance concrete (UHPC) KW - X-ray diffraction (XRD) KW - Sample holder KW - Fast measurement KW - Spatial analyses PY - 2018 DO - https://doi.org/10.1061/(ASCE)MT.1943-5533.0002163 SN - 1943-5533 SN - 0899-1561 VL - 30 IS - 3 SP - 06018001, 1 EP - 06018001, 5 PB - American Society of Civil Engineers CY - Reston, VA, USA AN - OPUS4-43879 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Sebastian A1 - Meng, Birgit A1 - Selleng, Christian T1 - A new sample holder for fast xrd investigation on UHPC N2 - A new sample holder is described in this poster. It was developed in BAM for fast XRD investigation on UHPC (ultra high performance concrete). Results measuring solid, i.e. not pulverized, samples are shown. T2 - GeoBerlin 2015 CY - Berlin, Germany DA - 04.10.2015 KW - Building Materials KW - UHPC KW - X-ray diffractometry PY - 2015 AN - OPUS4-36949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Budnik, J. A1 - Betz, T. A1 - Fromm, A. A1 - Gerdes, A. A1 - Gerlach, J. A1 - Götz, M. A1 - Hintzen, W. A1 - Hüttl, R. A1 - Kämpfer, W. A1 - König, A. A1 - Kühner, S. A1 - Lohaus, L. A1 - Meng, Birgit A1 - Neumann, T. A1 - Patzer, M. A1 - Schaab, A. A1 - Schauerte, J. A1 - Siebert, B. A1 - Stephan, D. A1 - Tebbe, H. A1 - Wagner, J.-P. ED - Siebert, B. T1 - Chemischer Angriff auf Betonbauwerke - Bewertung des Angriffsgrads und geeignete Schutzprinzipien N2 - In verschiedenen Bereichen des Betonbaus ist Beton einem chemischen Angriff von außen ausgesetzt, der die Dauerhaftigkeit des betreffenden Bauteils bzw. des gesamten Bauwerks beeinträchtigen kann. Für einen chemischen Angriff in natürlichen Böden und Grundwässern bestehen normative Vorgaben in DIN 4030-1 [R10] bzw. DIN 1045-2 [R19], um den Angriffsgrad anhand der Art und Konzentration der angreifenden Stoffe in Expositionsklassen XA1 (schwach angreifend) bis XA3 (stark angreifend) einzustufen. Hinsichtlich weiterer maßgeblicher Einflussfaktoren wird an dieser Stelle nicht näher differenziert, ob und inwieweit die Regelungen für Böden und Grundwässer auch auf andere Bereiche mit chemischem Angriff auf Beton zu übertragen sind, ist stets im Einzelfall zu überprüfen. Ebenfalls sind die zu treffenden Maßnahmen über die Vorgaben der DIN EN 206-1/DIN 1045-2 [R19] hinaus anwendungsspezifisch festzulegen. Der Hauptausschuss Baustofftechnik (HABT) des DBV hat daher den Arbeitskreis "Chemischer Angriff auf Beton" beauftragt, dieses Merkblatt zu erarbeiten, das Hilfestellung bei der Bewertung einer projektspezifischen chemischen Angriffssituation auf Beton sowie bei der Planung und Ausführung von Schutzprinzipien leisten soll. KW - Beton KW - Betonangriff KW - Dauerhaftigkeit KW - Säureangriff KW - Sulfatangriff PY - 2014 SP - 1 EP - 101 PB - Eigenverlag Deutscher Beton- und Bautechnik-Verein e. V. CY - Berlin AN - OPUS4-44662 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Budnik, J. A1 - Betz, T. A1 - Brameshuber, W. A1 - Fromm, A. A1 - Gerdes, A. A1 - Gerlach, J. A1 - Götz, M. A1 - Hart, R. A1 - Heese, C. A1 - Hintzen, W. A1 - Hüttl, R. A1 - Kämpfer, W. A1 - König, A. A1 - Kühner, S. A1 - Lohaus, L. A1 - Meng, Birgit A1 - Neumann, T. A1 - Remus, R. A1 - Schaab, A. A1 - Schäffel, P. A1 - Schauerte, J. A1 - Schönborn, A. A1 - Siebert, B. A1 - Stephan, D. A1 - Tebbe, H. A1 - Wagner, J.-P. ED - Siebert, B. T1 - Chemischer Angriff auf Beton - Empfehlungen zur Prüfung und Bewertung N2 - ln den letzten Jahren wurden diverse Prüfverfahren und Methoden entwickelt, um die Leistungsfähigkeit von Beton bzw. Bindemittel hinsichtlich des Widerstands gegenüber betonaggressiven Einwirkungen beurteilen zu können. Ein wesentliches Ziel von Prüfverfahren zur Beurteilung der Dauerhaftigkeit von Baustoffen ist, die im Laufe der Nutzungsdauer zu erwartenden Einwirkungen auf den Baustoff realitätsnah abzubilden. Dazu sind die Prüfparameter auf die im jeweiligen Anwendungsbereich vorherrschenden Umgebungs- und Randbedingungen anzupassen. Daneben sind auch die Bewertungskriterien individuell unter Berücksichtigung der im Einzelfall geforderten Nutzungsdauer eines Bauwerks festzulegen. Eine systematische Zuordnung von adäquaten Prüfverfahren bzw. Prüfparametem und Bewertungskriterien für die verschiedenen Anwendungsbereiche im Betonbau, in denen betonaggressive Einwirkungen auftreten, ist mit Ausnahme von Einzelfällen bislang nicht vorhanden. Daneben stellt sich in der Praxis immer wieder das Problem, das Angriffspotenzial der Umgebung eines Bauwerks (prüftechnisch) zu erfassen und zu bewerten. Der Hauptausschuss Baustofftechnik des DBV hat daher den Arbeitskreis „Chemischer Angriff auf Beton“ beauftragt, dieses Merkblatt zu erarbeiten, das auf Basis von einschlägigen Erfahrungen der Baupraxis und wissenschaftlichen Erkenntnissen Grundsätze und bewährte Methoden zur Beurteilung der Einwirkungs- und Widerstandsseite beim chemischen Angriff auf Beton aufzeigt und diesbezüglich Hinweise für verschiedene Anwendungsbereiche im Betonbau liefert. KW - Beton KW - Betonangriff KW - Dauerhaftigkeit KW - Säureangriff PY - 2017 SP - 1 EP - 65 PB - Eigenverlag Deutscher Beton- und Bautechnik-Verein e. V. CY - Berlin AN - OPUS4-44663 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stroh, Julia A1 - Meng, Birgit A1 - Emmerling, Franziska T1 - Deterioration of hardened cement paste under combined sulphatechloride attack investigated by synchrotron XRD N2 - The exact mechanisms of the phase transitions caused by a combined sulphate-chloride attack are discussed controversially. The main points concern the mutual influences of sulphate and chloride ions during the secondary binding processes of these anions within cement hydrate phases. We simulated combined sulphate-chloride attack under laboratory conditions using solutions containing NaCl and Na2SO4 in different concentrations. Three sample compositions were used for the preparation of the specimens. In two of them, 30% of Portland cement was replaced by supplementary cementitious materials (fly ash, slag). The phase distribution in the samples was determined using synchrotron X-ray diffraction. The analysis with high spatial resolution allows the localisation of the secondary phase formation in the microstructural profile of the sample. A mechanism of the phase developments under combined sulphate-chloride attack is derived. KW - Cement paste KW - Sulphate-chloride attack KW - Portland cement KW - Mineral additions PY - 2016 DO - https://doi.org/10.1016/j.solidstatesciences.2016.04.002 IS - 56 SP - 29 EP - 44 PB - Elsevier Masson SAS CY - Issy les Moulineaux cedex; France AN - OPUS4-35936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - von Werder, Julia A1 - Manninger, Tanja A1 - Maier, Bärbel A1 - Fladt, Matthias A1 - Simon, Sebastian A1 - Gardei, Andre A1 - Höhnel, Desirée A1 - Pirskawetz, Stephan A1 - Meng, Birgit T1 - A multiscale and multimethod approach to assess and mitigate concrete damage due to alkali-silica reaction N2 - Alkali-silica reaction (ASR) is a chemical reaction within concrete which can lead over time to cracking and spalling. Due to the complexity of the problem, it still causes damage to concrete constructions worldwide. The publication aims to illustrate the interdisciplinary research of the German Federal Institute for Materials Research and Testing (BAM) within the last 20 years, considering all aspects of ASR topics from the macro to the micro level. First, methods for characterization and assessment of ASR risks and reaction products used at BAM are explained and classified in the international context. Subsequently the added value of the research approach by combining different, preferably nondestructive, methods across all scales is explained using specific examples from a variety of research projects. Aspects covered range from the development of new test-setups to assess aggregate reactivity, to analysis of microstructure and reaction products using microscopical, spectroscopical and X-ray methods, to the development of a testing methodology for existing concrete pavements including in-depth analysis of the visual damage indicator and the de-icing salt input using innovative testing techniques. Finally, research regarding a novel avoidance strategy that makes use of internal hydrophobization of the concrete mix is presented. KW - Mitigation strategies KW - Concrete KW - Damage analysis KW - Alkali silica reaction KW - Road pavement KW - Accelerated testing KW - Non-destructive testing KW - Microstructure PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:101:1-2022052515100075090235 DO - https://doi.org/10.1002/adem.202101346 SN - 1527-2648 VL - 24 IS - 6 SP - 1 EP - 36 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tian, H. A1 - Voigt, Marieke A1 - Lehmann, C. A1 - Meng, Birgit A1 - Stephan, D. ED - Middendorf, B. ED - Fehling, E. T1 - Composition and microstructure stability of cement compound under cyclic hydrothermal condition N2 - There have been many researches focused on the performance improvement of ultra-high performance concrete (UHPC) by autoclaving treatment. The goal of autoclaving is to increase the pozzolanic reaction, and to densify the cement stone and the transition zone which originates from the incorporation of supplementary cementitious materials (SCMs), such as silica fume, fly ash and blast furnace slag. Due to the superior properties, UHPC can also be utilized under high mechanical load and aggressive condition, for example, the fabrication of water tanks for thermal storage which is of great significance for saving energy and reducing CO2 emission. It is known that mineral stability of the hydration products of an inorganic binder is highly related to the temperature and pressure of the environment. A certain stable composition at room temperature, however, may undergo a phase transformation at high temperature and the performance decrease under this severe condition will generally be more severe. In this way, the rationale behind this deterioration under long-term hydrothermal condition involving many cycles and long duration has to be clarified, and then appropriate optimizing methods will be performed in order to obtain a kind of construction with high durability under aggressive environment. For this purpose, different types and amounts of SCMs are introduced into the standard mixture of UHPC and the phase compositions after autoclaving at 200 °C and 15.5 bar are determined by combined X-ray diffraction and scanning electron microscope. Mercury intrusion porosimeter is used to characterise the microstructure of the samples. In order to establish the relationship between microstructure and macroscopic properties, compressive and flexural strength are also investigated. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - Hydrothermal treatment KW - UHPC KW - Composition PY - 2020 SN - 978-3-7376-0828-2 VL - 23 SP - 87 EP - 88 PB - Kassel University Press CY - Kassel AN - OPUS4-52375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schneider, M. A1 - Meng, Birgit T1 - Ressourcenschonung bei der Zementherstellung am Beispiel des Einsatzes von Hüttensand PY - 2002 SN - 3-7640-0426-6 SP - 10 EP - 14 PB - Verlag Bau + Technik CY - Düsseldorf AN - OPUS4-2069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Krütt, Enno A1 - Meng, Birgit T1 - AKR unter kombinierten Einwirkungen - Rissbildungs- und Transportmechanismen N2 - Die vorstehend dargestellten Untersuchungen lassen sich wie folgt zusammenfassen: • Mit dem für die mechanische Vorschädigung entwickelten Versuchsstand und gewählten Prüfregime können die für die ermüdungsinduzierte Schadensevolution typische stabilisierende und stabile Phase in der auf Zug beanspruchten Betonrandzone gut abgebildet werden. So wurde dort zum Beispiel, ausgehend von dem hier gewählten praxisnahen Belastungsregime, mit Ultraschall in der Ruhephase durch das Trockenschwingen ein maximaler Abfall des relativen dynamischen E-Moduls von ca. 8 - 10 % ermittelt. • Mit aufbauenden kapillaren Aufsaugversuchen wurde gezeigt, dass die erzeugte Betondegradation zu einer moderaten Erhöhung der Aufnahme des Prüfmediums führt. • Zur Bewertung der Auswirkungen einer alleinigen Vorschädigung (Trockenschwingen) auf die schädigende AKR mittels Performance-Prüfung ist die Klimawechsellagerung aufgrund der einseitigen Tausalzbeaufschlagung am besten geeignet. Die hier ermittelten Dehnungsverläufe lassen auf einen moderaten Einfluss der mechanischen Vorschädigung auf die AKR schließen. • Die zusätzlich im Kontext der Nasschwingversuche durchgeführten 60°C Betonversuche zeigen, dass die zyklische Beanspruchung vor und nach dem Aufbringen der Tausalzlösung die schädigende AKR gleichfalls moderat erhöht. In derzeit laufenden ergänzenden Untersuchungen wird der separate Einfluss der ermüdungsinduzierten Rissbildung auf die schädigende AKR an homogen, stärker geschädigten Prüfkörpern mit einem hohen inneren AKR-Schädigungspotenzial im 60°C Betonversuch grundhaft analysiert. Zusätzlich wird gegenwärtig der Einfluss der degradierten Betonrandzone auf die Dehnungsverteilung an großformatigen Prüfkörpern über die Höhe im 40°C Betonversuch vertiefend für die makroskopische Modellierung untersucht. T2 - 20. Internationale Baustofftagung ibausil CY - Weimar, Germany DA - 12.09.2018 KW - Betonfahrbahndecke KW - Alkali-Kieselsäure-Reaktion KW - Tausalz KW - LIBS KW - MRFA KW - Nasschemie KW - ZfP PY - 2018 SN - 978-3-00-059950-7 SP - 1 EP - 13 AN - OPUS4-46174 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bahlmann, Stefanie A1 - Rübner, Katrin A1 - Meng, Birgit T1 - Untersuchungen zur Verwertung industrieller Reststoffe als Ersatz von Primärrohstoffen in Mörtel und Beton N2 - Um den Abbau primärer Rohstoffe zu reduzieren, wurden deponierte oder niederwertig eingesetzte industrielle Reststoffe hinsichtlich einer höherwertigen Verwendung im Betonbau untersucht. Zur Bewertung des Einsatzpotentials als Zementbestandteil oder Betonzusatzstoff erfolgte zunächst eine chemisch-mineralogische und betontechnologische Charakterisierung der Materialien. Reststoffe, die die normativen Anforderungen hinsichtlich der Zementzusammensetzung erfüllen, wurden anschließend zu verschiedenen Anteilen als Zementsubstitut in Mörtel eingesetzt. In vergleichenden Untersuchungen erfolgte die Ermittlung der Frisch- und Festmörteleigenschaften. Kalorimetrische Untersuchungen sollten die Auswirkungen der Reststoffe auf die Zementhydratation zeigen. Ausgewählte Untersuchungsergebnisse an Reststoffen aus der Industrieabwasseraufbereitung, dem Altpapierrecycling, der Biomasseverbrennung und der Metallurgie werden vorgestellt. T2 - 17. Internationale Baustofftagung IBAUSIL 2009 CY - Weimar, Germany DA - 23.09.2009 KW - Industrieabwasseraufbereitung KW - Altpapierrecycling KW - Biomasseverbrennung KW - Metallurgie PY - 2009 AN - OPUS4-36516 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wiens, U. A1 - Meng, Birgit T1 - Zur Eignung von Hochleistungsbetonen bei chemischem Angriff N2 - Ende der 1990er-Jahre beauftragte die Philipp Holzmann AG das Institut für Bauforschung der RWTH Aachen (ibac) mit der Durchführung von Untersuchungen zur Eignung von Hochleitsungsbetonen bei chemischem Angriff. Im Rahmen des Forschungsvorhabens sollte geprüft werden, inwieweit die Möglichkeit besteht, durch betontechnische Maßnahmen die Widerstandsfähigkeit des Betons zu erhöhen, wodurch evtl. erforderliche Schutzmaßnahmen entfallen können. Aus diesem Grund wurden Hochleistungsbetone mit sehr niedrigen Wasserbindemittelwerten unter Verwendung von anorganischen (Silicastaub und Steinkohlenflugasche) und organischen (Polymerdispersion auf Basis von Styrolacrylat) Betonzusatzstoffen hergestellt, in verschiedenen betonangreifende Medien (5%ige Ammoniumnitratlösung, Essigsäure (pH 3,5), sowie Müll-, Klärwasser und Sulfatläsung) eingelagert und das Ausmaß der Schädigung ermittelt. Der Beitrag fasst die bisher noch nicht veröffentlichten Ergebnisse dieser Untersuchungen zusammen. KW - Baustoffe KW - Beton KW - Dauerhaftigkeit KW - Chemischer Angriff PY - 2017 SN - 978-3-00-056692-9 SP - 458 EP - 472 CY - Bochum AN - OPUS4-42971 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke A1 - Gardei, Andre A1 - Meng, Birgit ED - di Prisco, M. ED - Meda, A. ED - Balazs, G.L. T1 - The adaption of the set-up for gas permeability measurements for ultra-high performance concrete N2 - In the framework of this project, a steam pressure vessel was to be developed from ultra-high perfor-mance concrete (UHPC) to withstand process temperatures of 200 °C and the respective steam pressure of 15,5 bar. To guarantee the long-term water vapour tightness of the system, the permeability of two UHPC mixtures were tested after long-term cyclic autoclaving. As UPHC shows a high density and therefore low permeability, measurements after the RILEM-Recommendation (TC 116-PCD) reached their detection limit. Therefore, the measurement set-up was adapted to measure the permeability of highly dense UHPC more reliably and quickly. This adaption includes measurements in a higher pres-sure range, the change of sample size thickness and the usage of Ar as a medium compared with the RILEM Recommendation. Additionally, the system was equipped with two pressure sensors and Ar-flowmeters to guarantee a continuous record of the experimental parameters. The new system was tested and evaluated by comparing measurements with the RILEM recommended system. Preliminary results show that the adapted system is capable to provide efficient and reliable results of concrete with low permeability. T2 - 14th fib PhD Symposium in Civil Engineering CY - Rom, Italy DA - 05.09.2022 KW - Durability KW - UHPC KW - gas permeability PY - 2022 SN - 978-2-940643-17-2 SN - 2617-4820 VL - 58 SP - 353 EP - 359 AN - OPUS4-56862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fontana, Patrick A1 - Müller, Urs A1 - Malaga, Katarina A1 - Lagerblad, B. A1 - Meng, Birgit T1 - Precast concrete facade elements with low embodied energy N2 - Concrete is by far the most common building material in the world. Due to its good durability it is widely used in building envelopes. One major part of the embodied energy in concrete comes from the production of Portland cement that consumes around 3,500 MJ energy per each ton of cement. Globally 2.6 billion tons of Portland cement is produced and the consumption is increasing. Since concrete will be used as main building material also in future construction, it is reasonable to develop concrete building components with lower embodied energy.Using the example of an ultra-high performance concrete (UHPC) façade element, it is demonstrated how the embodied energy can be reduced by application of hydrothermal curing. T2 - ENBRI Workshop - reaching the nearly zero-energy goal for buildings CY - Boras, Sweden DA - 04.04.2011 KW - UHPC KW - Betonfertigteil KW - Fassaden KW - Autoklavierung KW - Nachhaltigkeit PY - 2011 SN - 978-91-86622-51-0 SN - 0284-5172 SP - 1 EP - 8 AN - OPUS4-23628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breitenbücher, R. A1 - Przondziono, R. A1 - Meng, Birgit A1 - Krütt, Enno A1 - Weise, Frank T1 - Alkali-Silica Reaction in concrete pavements considering traffic and de-icing agents N2 - In concrete pavements, damages occurred which are related to an Alkali-Silica-Reaction (ASR). Although the background for such an ASR has been studied extensively, special conditions in pavements increase this reaction significantly. These are especially the superposition of microstructural degradation caused by cyclic loading with an external alkali supply. Previous investigations of ASR focused mainly on the material itself (aggregates, cements, assessment of the concrete) while these special circumstances have not been considered. Concrete pavements are subjected to cyclic loadings by traffic and climate changes. Within cooperative research projects the different interdependent influencing factors for a damaging ASR in concrete pavements are studied by experiments as well as by numeric modelling. On the micro-level the ASR-related processes within the aggregate, such as gel-formation or ion-transport, are investigated. On the meso-level, the project focuses on the characterization of degradation effects in the concrete microstructure due to cyclic loading. Further, special attention is paid to the transport behavior of fluids in such pre-damaged concrete structures with and without the effect of overrunning tires as well as the impact on the ASR itself. Finally, on the macro-level the risk of an ASR-damage is assessed. T2 - 13th International Symposium on Concrete Roads CY - Berlin, Germany DA - 19.06.2018 KW - Alkali-Silica Reaction KW - Degradation KW - Cyclic loading KW - Fluid transport KW - Traffic PY - 2018 SP - 1 EP - 15 AN - OPUS4-46354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Meng, Birgit A1 - Pirskawetz, Stephan A1 - Voland, K. T1 - Influence of simultaneous cyclic loading and external alkali supply on the alkali-silica reaction in concrete pavements N2 - In recent years the German motorway network has seen an increase in the occurrence of damage to concrete road surfaces which can be attributed to the alkali-silica reaction (ASR). In view of the often drastically reduced life expectancy of road surfaces due to ASR, research activity in this field has notably increased. Alongside preventative measures in concrete technology, the main research focus up to now has been the development of performance-oriented testing procedures for ASR prevention. This included more specifically the accelerated simulation of climatic effects and external alkali penetration on road surfaces. The effects of mechanical pre-damage resulting from cyclic traffic loading and climatic impact had previously not been taken into consideration. Since 2011, the five-partner research group 1498 sponsored by the German Research Foundation (DFG) has been pursuing research on how simultaneous cyclic loading and external alkali penetration impacts destructive ASR in road surface concretes. The depiction of the myriad degradation and transport processes necessary for an understanding of these effects requires close interaction between experiments and their multi-scale modelling. This paper aims to focus on the aforementioned experiments by means of innovative testing techniques. The research is founded on a series of cyclic fatigue tests performed on large-format beams, both with and without previous application of a sodium chloride (NaCl) solution, with simultaneous tracking of crack development. Subsequently, smaller test specimens were extracted from the pre-damaged beams for further experiments. These included the spatial visualization and quantification of fatigue-induced cracks using micro X-ray 3D-computed tomography (3D-CT). Additionally, the effects of fatigue-induced cracks on alkali transport were investigated using Laser-Induced Breakdown Spectroscopy (LIBS). Subsequent storage of the small-format test specimens, with and without cyclic pre-damage, in an ASR-conducive environment then provided initial findings on the influence of fatigue-induced predamage on the ASR. T2 - 15th International Conference on Alkali-Aggregate reaction (ICAAR 2016) CY - Sao Paulo, Brazil DA - 03.07.2016 KW - concrete pavements KW - alkali-silica-reaction KW - fatigue KW - damage monitoring PY - 2016 SP - Paper 191 AN - OPUS4-37142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Werner, Daniel A1 - Meng, Birgit A1 - Weise, Frank T1 - Influence of aggregate size on the damage potential of alkali-silica reaction N2 - The susceptibility of different aggregate types used in concrete to ASR is strongly associated with their petrography. The aim of this study is to assess the influence of the aggregate size on the ASR potential, in particular applied to the sand fractions in the size range of 0.125-4 mm. The investigation concept is based on the hypothesis that at a specific particle size reactive aggregates could change their characteristic influence in mitigating ASR instead of promoting it. For the study of the size dependent behaviour mortars are prepared, considering aggregates of different reactivity, including very reactive, slow-late and quasi non-reactive types. The analysis is based on a stepwise substitution concept, in which mortars with a constant overall grain size distribution are compared, while only one size fraction of the non-reactive base aggregate is substituted by a reactive aggregate type of this specific size fraction. For the expansion experiments an accelerated mortar bar test (80°C, immersed in NaOH solution) was applied. The results show that the slow-late reactive greywacke yielded a strong reduction of the expansion below an aggregate size in the range of 0.5-1 mm. On the other side with the very reactive borosilicate glass, the expansions increased steadily with decreasing size. To validate if the acquired expansions were caused by ASR, thin sections were analysed. Mainly, higher expansion values were consistent with extensively more amounts of ASR indicators. T2 - 15th International Conference on Alkali-Aggregate Reaction (ICAAR 2016) CY - Sao Paulo, Brazil DA - 03.07.2016 KW - alkali-silica-reaction KW - building materials KW - concrete KW - durability PY - 2016 SP - Paper 194 AN - OPUS4-37143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Raupach, M. T1 - Einfluss ausgewählter Modifikationen der Mischungszusammensetzung auf die Eigenschaften von Instandsetzungsmörteln N2 - Trotz der zahlreichen Möglichkeiten zur Beeinflussung der Mörteleigenschaften durch Mischungsmodifikationen ist es nahezu unmöglich, einzelne Eigenschaften unabhängig von anderen zu verändern. Bei einer Mischungsoptimierung muss im Einzelfall immer entschieden werden, welcher der gewünschten Eigenschaften die höchste Priorität zukommt. Anhand von Parameterstudien wird im vorliegenden Artikel verdeutlicht, wie es für bestimmte Anwendungen sinnvoll sein kann, die Verschlechterung einzelner Eigenschaften zu akzeptieren, wenn dadurch eine für den speziellen Einsatzfall essenzielle Eigenschaft verbessert werden kann. Die komplexen Wechselwirkungen der einzelnen Bestandteile fuhren dazu, dass auch scheinbar widersprüchliche Kombinationen von Zusatzmitteln im Einzelfall erforderlich werden können. Zur Anpassung der meisten Mörteleigenschaften gibt es verschiedene Möglichkeiten der Zielerreichung mit jeweils unterschiedlichen Nebeneffekten. Frisch- und Festmörteleigenschaften sind dabei gleichermaßen zu beachten. T2 - 2. Kolloquium "Erhaltung von Bauwerken" CY - Ostfildern/Stuttgart, Germany DA - 25.01.2011 KW - Betoninstandsetzung KW - Instandsetzungsmörtel KW - Modulare Systeme KW - Polymer cement mortar (PCC) KW - Sprayed polymer cement mortar (SPCC) PY - 2011 SN - 3-924813-87-6 SP - 213 EP - 221 AN - OPUS4-23218 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Urs A1 - Lehmann, Christian A1 - Fontana, Patrick A1 - Meng, Birgit T1 - Effects of autoclaving on the nano structure and phase composition of ultra high performance concrete T2 - 12th Euroseminar on microscopy applied to building materials CY - Dortmund, Germany DA - 2009-09-15 KW - UHPC KW - Micro structure KW - Autoclaving KW - Phase stability KW - C-S-H PY - 2009 SN - 978-3-00-028697-1 SP - 351 EP - 359 AN - OPUS4-20622 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Feuchtemessung in kapillarporösen Baustoffen T2 - DAfStb Fachtagung "Betonbauten als Dichtkonstruktionen" CY - Berlin, Germany DA - 2004-03-12 PY - 2004 AN - OPUS4-5382 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiens, U. A1 - Meng, Birgit A1 - Fontana, Patrick T1 - Mikrorissbildung in Hochleistungsbeton - Vom Modell zu den Auswirkungen auf Betoneigenschaften KW - Hochleistungsbeton KW - Silikastaub KW - Mikrorissbildung PY - 2007 SN - 0005-9846 VL - 57 IS - 6 SP - 256 EP - 265 PB - Verlag Bau + Technik CY - Erkrath AN - OPUS4-15009 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit A1 - Fontana, Patrick A1 - Müller, Urs A1 - Kühne, Hans-Carsten T1 - Nanotechnologische Anwendungen im Baustoffbereich T2 - Nanotechnologie und Bauwesen (NanoTecture) CY - Düsseldorf DA - 2006-12-05 KW - Nanotechnologie KW - Analytik KW - Gefüge KW - Zement KW - Beton PY - 2006 SP - 13 EP - 27 CY - Düsseldorf AN - OPUS4-15703 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bahlmann, Stefanie A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. A1 - Klein, H. A1 - Müller, C. A1 - Ruppert, J. A1 - Schäfer, S. A1 - Spanka, G. A1 - Wassing, W. A1 - Zunzer, U. T1 - Potenziale des Sekundärstoffeinsatzes im Betonbau - Teilprojekt B1 KW - Nachhaltigkeit KW - Sekundäre Gesteinskörnung KW - Rezyklierte Gesteinskörnung KW - Betonbrechsand KW - Müllverbrennungsasche PY - 2007 SN - 978-3-410-65772-9 SN - 0171-7197 N1 - Geburtsname von Bahlmann, Stefanie: Ramolla, S. - Birth name of Bahlmann, Stefanie: Ramolla, S. IS - 572 SP - 131 EP - 222 PB - Beuth AN - OPUS4-16361 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit T1 - Properties of repair mortars - potentials and risks of a tailor-made mixture proportioning N2 - Despite the numerous possibilities to influence the properties of repair mortars by modifications of the mixture proportioning, it is almost impossible to change an individual property without influencing other mortar properties. When optimising a mixture, it has to be decided for each individual case, which of the mortar properties needs to be treated with the highest priority. Most properties can be altered by several different measures, which may vary in effectiveness, side effects and cost efficiency. As the prevention of shrinkage induced constraining cracks is crucial for the durability and Service life of a concrete repair task, in the presented paper special attention is paid to the influences on the mortar’s shrinkage behaviour. On the basis of parameter studies it is shown, how it may be beneficial in certain cases to accept the worsening of some general properties if by this measure another property, which is essential for the individual application task, can be enhanced significantly. In general a tailor-made approach for the mixture proportioning seems beneficial but due to the complexity of the constituents’ interactions in repair mortars, it bears a high risk of unexpected malfunctions. T2 - Concrete-Workshop 'Performance-based specifications for concrete' CY - Leipzig, Germany DA - 14.06.2011 KW - Repair mortar KW - Concrete rehabilitation KW - Repair systems KW - Polymer cement mortar (PCC) KW - Sprayed polymer cement mortar (SPCC) PY - 2011 SN - 978-3-9814523-0-3 SP - 319 EP - 329 AN - OPUS4-23985 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Drochytka, R. ED - Bohus, S. T1 - Natural stone reprofiling in cultural heritage with modular repair mortars N2 - Whenever the preservation of original substance obtains priority in a restoration task, reprofiling techniques using repair mortars are a welcome solution. For ordinary concrete repair aesthetic aspects are of minor importance whereas for the restoration of natural stone elements they come to the fore. Especially for listed buildings and monuments, historico-cultural and aesthetical interests become the ruling Parameters for planning and execution of restoration tasks. Nevertheless the technical and constructive requirements have to be considered and deterioration processes have to be understood to ensure sustainability and durability of the repair task. Due o differences in the Chemical and mineralogical composition, natural stone provides a vast variety of texture and colour. Also the range of different mechanical and durability related properties is far wider than found with concrete for example. A research project dealing with the development of a modular repair mortar System for natural stone is currently set up at the BAM. To provide the conservator with the best possible options to match colour, texture and technical requirements, the System will be setup on a modular basis. Several different binder Systems on basis of cement, lime and sodium Silicate as well as polymer based Systems are planned, which can be combined with different aggregate compositions and different pigments. To evaluate the mortar performance, test procedures will be defined for tests on mortar samples and on composite specimens. In the paper the experimental Programme will be explained and first results will be presented and discussed. T2 - 2nd WTA - Internaitonal PhD Symposium - Building materials and buidling technology to preserve the built heritage CY - Brno, Czech Republic DA - 06.10.2011 PY - 2011 SN - 978-3-937066-21-9 SN - 0947-6830 N1 - Serientitel: WTA-Schriftenreihe – Series title: WTA-Schriftenreihe IS - 36 SP - 208 EP - 216 PB - WTA Publications AN - OPUS4-24837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herbst, Tristan A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. T1 - Sustainable evaluation - concept to assess the applicability of secondary aggregates in concrete N2 - Nowadays there are several applications of mineral recycling materials and residues. At present an assessment method for the use of secondary raw materials, which considers sustainability aspects, does not exist. In the framework of the German DAfStb/BMBF research project “Sustainable Building with Concrete” an assessment concept was developed. It includes the following four assessment steps: I. Basic considerations, II. Advantages for sustainable construction, III. Alternative paths for application, and IV. Sensitivity analysis. The concept was developed on the basis of recycled concrete aggregates, which are already used according to German standards. Afterwards, it was applied and verified by the evaluation of the utilisation of municipal solid waste incinerator bottom ashes (referred to MSWI bottom ashes). T2 - 2011 Helsinki world sustainable building conference CY - Helsinki, Finland DA - 18.10.2011 KW - Sustainable building KW - Sustainability aspects KW - Secondary materials KW - Secondary aggregates in concrete KW - Energy and material resources KW - Assessment concept PY - 2011 SN - 978-951-758-534-7 SN - 0356-9403 SP - 1 EP - 8 AN - OPUS4-24781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit A1 - Müller, Urs A1 - Fontana, Patrick ED - Rogge, A. ED - Meng, B. T1 - Neue Erkenntnisse und Analysemethoden zum Phasenbestand und Gefüge des Zementsteins T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 KW - Baustoffe KW - Zement KW - Mörtel KW - Mineralogische Zusammensetzung PY - 2011 SN - 978-3-9814281-0-0 SP - 11 EP - 17 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25198 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voland, Katja A1 - Weise, Frank A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Untersuchung des Einflusses der Gefügedichte von Betonen auf die AKR mit neuartiger Prüftechnik T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 KW - Alkali-Kieselsäure-Reaktion KW - Nebelkammerlagerung bei 40° C KW - 60° C-Betonversuch KW - Dehnungsmessung KW - Schallemissionsanalyse KW - Ultraschallgeschwindigkeit KW - mu-3D-CT PY - 2011 SN - 978-3-9814281-0-0 SP - 86 EP - 95 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25199 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rübner, Katrin A1 - Herbst, Tristan A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Ressourcenschonung durch Reststoffverwertung im Betonbau T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 283 EP - 294 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-25175 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Urs A1 - Meng, Birgit A1 - Bürgisser, Philip ED - Rogge, A. ED - Meng, B. T1 - Das natürliche Puzzolan 'Rheinischer Trass' und dessen Einfluss auf eine Alkali-Kieselsäure-Reaktion (AKR) in Beton T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 PY - 2011 SN - 978-3-9814281-0-0 SP - 141 EP - 150 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25187 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pistol, Klaus A1 - Weise, Frank A1 - Meinel, Dietmar A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Zur Wirkungsweise von Polypropylen-Fasern in brandbeanspruchten Hochleistungsbetonen T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 KW - Polypropylen-Fasern KW - Hochfester Beton KW - Schallemissionsanalyse KW - Röntgen 3D-Computertomographie KW - Rasterelektronenmikroskopie PY - 2011 SN - 978-3-9814281-0-0 SP - 134 EP - 140 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25188 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krütt, Enno A1 - Weise, Frank A1 - Meng, Birgit T1 - Einfluss einer druckschwellinduzierten Degradation von Fahrbahndeckenbeton auf die schädigende AKR T1 - Influence of cyclic compressive loading induced degradation of road pavement concrete on harmful AAR N2 - In den letzten Jahren sind im deutschen Bundesautobahnnetz verstärkt Schäden an vor 2005 errichteten Betonfahrbahndecken aufgetreten, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden. Neben dem AKR-fördernden Einfluss von alkalihaltigen Taumitteln werden Fahrbahndecken zyklischen mechanischen Belastungen infolge des Verkehrs und Zwangsspannungen durch klimatische Einwirkungen ausgesetzt. Solche mechanischen Belastungen werden bisher in keinem AKR-Prüfverfahren berücksichtigt. Die zyklischen Belastungen können zu einer Degradation des Betongefüges führen, die ggf. einen AKR-fördernden Einfluss hat. Dieser Beitrag stellt Untersuchungen vor, die zur Beantwortung der Frage nach dem Einfluss einer zyklischen mechanischen Belastung auf den AKR-Schadensprozess beitragen. Dabei wird der Hypothese nachgegangen, dass die ermüdungsinduzierte Degradation zu einer Erhöhung des Stofftransports führt. Dieser hat einen Einfluss auf die AKR-Schadensentwicklung, da die Reaktionspartner zunächst zum Reaktionsort transportiert werden müssen. Daher wird angenommen, dass sich mit dem Stofftransport auch die AKR-Schädigung verstärkt. Es werden Betonproben aus typischen Fahrbahndeckenbetonen einer vorgeschalteten zyklischen Druckschwellbelastung ausgesetzt. Die Degradation infolge der Vorbelastung wird simultan mittels ZfP-Verfahren charakterisiert. Anschließend werden die Auswirkungen der zyklischen Vorschädigung auf den Stofftransport sowie auf die AKR vergleichend an Prüfkörpern ohne und mit Vorschädigung untersucht. Die Ergebnisse lassen den Schluss zu, dass die zyklische Vorschädigung sowohl den Stofftransport als auch die AKR fördert. N2 - In recent years the German motorway network has seen an increase in the occurrence of damage to concrete road surfaces built before 2005, which can be attributed to the alkali-silica reaction (ASR). In addition to exposure to ASR-stimulating alkalirich deicing-agents, road surfaces are also subjected to cyclical mechanical loading resulting from traffic and induced stresses due to climatic impact. Such mechanical loadings are not considered in any of the previously developed ASR testing procedures. This cyclical loading could, however, lead to a degradation of the concrete microstructure and, in turn, stimulate the ASR-process. This article presents investigations that contribute to answering the question of whether a mechanically induced degradation influences the ASR-process. The hypothesis that the mechanically induced degradation leads to an increase in mass transport is examined. The mass transport is important for the ASR process because the reactants need to be transported to the reaction location before the reaction can take place. Therefore, it is assumed that increased mass Transport also leads to increased ASR damage. Concrete specimens made of typical pavement concretes are subjected to a predamaging cyclic compressive loading. The degradation is characterized simultaneously during the pre-damaging process using non-destructive testing (NDT) techniques. Then the effects of the cyclical pre-damage on the mass transport as well as on the ASR are determined by comparing results from test specimens with and without pre-damage. The results lead to the conclusion that the cyclical pre-damage increases both the mass transport and the ASR. KW - Stofftransport KW - Betonfahrbahndecken KW - AKR KW - Zyklische Belastung KW - Degradation PY - 2020 DO - https://doi.org/10.1002/best.202000017 SN - 0005-9900 VL - 115 IS - 10 SP - 779 EP - 788 PB - Wilhelm Ernst & Sohn CY - Berlin AN - OPUS4-51561 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke A1 - von Werder, Julia A1 - Meng, Birgit ED - Middendorf, B. ED - Fehling, E. T1 - Microstructure analysis of thermally treated ultra high performance concrete in the context of the durability performance N2 - Ultra high performance concrete (UHPC) is known for its high compressive strength of more than 150 MPa and its high durability. Thermal treatment at 90°C can accelerate the strength development so that the 28-days-strength can be achieved immediately after the treatment and an additional increase up to 30 % in some cases. The reason for the strength development is an accelerated hydration of the clinker minerals and an intensified pozzolanic reaction leading to a denser microstructure. In previous research inhomogeneities in form of a zonation after unprotected thermal treatment were observed and analysed in respect to changes in the microstructure. This zonation is defined by a different microstructure in the core compared to the outer zone in the matter of porosity, mineral phase composition and a significant change in the potassium and sulphur concentration of the zones is measurable. To isolate different transport mechanisms responsible for these element distributions UHPC samples were thermally treated at 90 °C and the microstructure was investigated under dry conditions and after immersion in water to investigate the influence of dehydration during and rehydration after the thermal treatment on the microstructure. Through durability testing via water absorption, water vapour diffusion, permeability testing and sulfuric acid resistance transport mechanisms like diffusion, migration, capillary suction are under investigation in correlation with the microstructure analysis. For the microstructure analysis measurements with µXRF, mercury intrusion porosity, XRD and SEM were conducted. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - UHPC KW - Thermal treatment KW - Zonation KW - Transport mechanism KW - Durability PY - 2020 SN - 978-3-7376-0828-2 DO - https://doi.org/10.17170/kobra-202002271026 VL - 23 SP - 151 EP - 152 PB - Kassel University Press CY - Kassel AN - OPUS4-52373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Marieke A1 - von Werder, Julia A1 - Meng, Birgit T1 - Investigation of the zonation of thermally treated ultra high performance concrete N2 - Ultra high performance concrete (UHPC) is characterised by its high compressive strength of more than 120 MPa and its high durability. With thermal treatment at 90°C, hydration is accelerated and a strength comparable to the 28-day strength can be achieved immediately after the treatment. In applying Optimum process conditions, the strength can be even further increased by up to 30%. Previous Research showed that thermal treatment can lead to inhomogeneities in form of a visible zonation within the cross-section, if the UHPC is not protected sufficiently from desiccation. This led to the question, to what extent the related changes in mechanical properties, microstructure and phase composition are of relevance for the performance of the UHPC. First investigations of small specimens thermally treated without protection exhibited a decrease of compressive strength, indicating that the zonation aspect requires further research. In this study the zonation of UHPC treated thermally at 90°C is investigated after applying four different procedures of treatment and curing in comparison. The samples are characterized with respect to their chemistry, mineral composition and microstructure to allow an assessment on durability and strength development, with focus on potential depth dependent changes associated with the zonation. The measurements reveal the formation of a visible zonation in case of unprotected treatment, if followed by immersion in water. The compressive strength is not significantly impaired, but a decrease in bending strength gives reason for concern. Further results allow clear correlation with changes in pore structure, whereas the interpretation of relationships with phase distribution, degree of hydration, microchemistry is more complex and therefore, provides only partial clarification. KW - UHPC KW - Thermal treatment KW - Zonation KW - Desiccation KW - Microstructure KW - Durability PY - 2020 DO - https://doi.org/10.1016/j.conbuildmat.2020.119187 VL - 254 SP - 119187 PB - Elsevier Ltd. AN - OPUS4-50828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Possibilities for improving the properties of UHPC by means of thermal treatment N2 - A further improvement of the excellent properties of UHPC can be realized with thermal Treatment. Like for normal concrete, it accelerates the hardening and prevents shrinkage after the treatment. Additionally, an increase in strength can be achieved. Aim of this study was the optimisation of the thermal Treatment conditions of UHPC for very different Treatment methods; heat Treatment at 90 °C for unprotected and sealed samples, hot water bath at 90 °C and hydrothermal Treatment at 185 °C/1.1 MPa. The pre-storage time and the dwell time were systematically varied for each method to gain a higher strength. The compressive strength depends on the manner of Treatment at which higher water accessibility leads to higher strengths. The Phase composition changes considerably with different Treatment tempereatures. Finally, it can activate unhydrated binder components forming additional C-S-H, leading to higher strength. T2 - International Symposium on Ultra-High Perfomance Fibre-Reinforced Concrete UHPFRC 2017 CY - Montpellier, France DA - 02.10.2017 KW - Building Materials KW - Ultra-High Performance Concrete (UHPC) KW - Heat treatment KW - Autoclaving KW - X-ray diffraction (XRD) PY - 2017 AN - OPUS4-42570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rachmatulin, Natalia A1 - Gardei, André A1 - von Werder, Julia A1 - Meng, Birgit A1 - Süßmuth, J. A1 - Gerdes, A. A1 - Ballschuh, D. A1 - Seibt, H. T1 - Funktionalisierung von Polymerfasern - ein Beitrag der Tensidchemie für dauerhafte zementgebundene Werkstoffe N2 - Im Gegensatz zur Druckfestigkeit weisen zementgebundene Werkstoffe i. a. nur geringe Zugfestigkeiten auf. Ein Weg, Zugfestigkeiten zementgebundener Werkstoffe zu erhöhen und Rissbildung aufgrund von Zugspannungen zu verringern, besteht in der Einarbeitung von Fasern, die diese Spannungen aufnehmen. Häufig eingesetzt werden Stahlfasern, obwohl synthetische Polymerfasern leichter und meist beständiger gegenüber chemischen Angriffen und Korrosion sind. Die Polymerfasern zeigen allerdings meist einen deutlich schwächeren Haftverbund, was an der hydrophoben Faseroberfläche liegt. Um nun eine Anbindung der Fasern an die mineralische Matrix zu erreichen, müssen die Faseroberflächen modifiziert werden, ohne dass die mechanischen Eigenschaften negativ beeinflusst werden. Eine Herausforderung besteht somit in einer Oberflächenmodifikation durch eine schonende Behandlung der Fasern zur Erzeugung von anbindungsfähigen Gruppen. Durch eine Behandlung von modifizierten Fasern mit geeigneten Polymerlösungen werden die Oberflächeneigenschaften verändert und erlauben eine Anbindung an die Zementsteinmatrix. Der Einsatz von Tensiden als grenzflächenaktive Verbindungen ermöglicht in diesem Zusammenhang eine Vermittlung zwischen Polymeroberflächen und mineralischen Werkstoffen. T2 - HighTechMatBau CY - Berlin, Germany DA - 31.01.2018 KW - Zementgebundene Baustoffe KW - Lichtmikroskopie KW - Röntgen-3D-Computertomographie KW - Einzelfaserdurchzugsversuch KW - Windkanal KW - Fasermodifikation KW - Oberflächenfunktionalisierung KW - Grenzflächenaktive Verbindung PY - 2018 SN - 978-3-7388-0082-1 SP - 31 EP - 35 PB - Fraunhofer IRB Verlag CY - Stuttgart AN - OPUS4-44651 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rachmatulin, Natalia A1 - Gardei, André A1 - von Werder, Julia A1 - Meng, Birgit A1 - Süßmuth, J. A1 - Gerdes, A. T1 - Funktionalisierung von Polymerfasern - ein Beitrag der Tensidchemie für dauerhafte zementgebundene Werkstoffe N2 - Im Gegensatz zur Druckfestigkeit weisen zementgebundene Werkstoffe i. a. nur geringe Zugfestigkeiten auf. Ein Weg, Zugfestigkeiten zementgebundener Werkstoffe zu erhöhen und Rissbildung aufgrund von Zugspannungen zu verringern, besteht in der Einarbeitung von Fasern, die diese Spannungen aufnehmen. Häufig eingesetzt werden Stahlfasern, obwohl synthetische Polymerfasern leichter und meist beständiger gegenüber chemischen Angriffen und Korrosion sind. Die Polymerfasern zeigen allerdings meist einen deutlich schwächeren Haftverbund, was an der hydrophoben Faseroberfläche liegt. Um nun eine Anbindung der Fasern an die mineralische Matrix zu erreichen, müssen die Faseroberflächen modifiziert werden, ohne dass die mechanischen Eigenschaften negativ beeinflusst werden. Eine Herausforderung besteht somit in einer Oberflächenmodifikation durch eine schonende Behandlung der Fasern zur Erzeugung von anbindungsfähigen Gruppen. Durch eine Behandlung von modifizierten Fasern mit geeigneten Polymerlösungen werden die Oberflächeneigenschaften verändert und erlauben eine Anbindung an die Zementsteinmatrix. Der Einsatz von Tensiden als grenzflächenaktive Verbindungen ermöglicht in diesem Zusammenhang eine Vermittlung zwischen Polymeroberflächen und mineralischen Werkstoffen. T2 - HighTechMatBau CY - Berlin, Germany DA - 31.01.2018 KW - Zementgebundene Baustoffe KW - Lichtmikroskopie KW - Röntgen-3D-Computertomographie KW - Einzelfaserdurchzugsversuch KW - Windkanal KW - Fasermodifikation KW - Oberflächenfunktionalisierung KW - Grenzflächenaktive Verbindung PY - 2018 AN - OPUS4-44652 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giebson, C. A1 - Voland, K. A1 - Ludwig, H.-M. A1 - Meng, Birgit T1 - Alkali-silica reaction performance testing of concrete considering external alkalis and preexisting microcrack N2 - In concrete elements, simultaneously subjected to cyclic loadings and external alkalis, the risk for damage caused by or under participation of an alkali-silica reaction (ASR) is particularly high. This is of particular concern for concrete pavements due to the increasing heavy vehicle traffic and the application of sodium chloride (NaCl) de-icer during winter. Since 2004, the climate simulation concrete prism test (CS-CPT) has been used successfully to evaluate job mixtures for pavements by considering the impact of alkali-containing de-icers. However, the role of mechanical predamage on ASR is largely unclear. In a joint research project, the CS-CPT has been used to investigate the influence of preexisting microcracks on ASR. It was evident that an ASR initiated earlier in the predamaged concrete prisms due to the more rapid ingress of NaCl solution through the microcracks. KW - Alkali-silica reaction KW - Climate simulation concrete prism test KW - External alkalis KW - Laser-induced breakdown spectroscopy KW - Microcracks KW - Pavement concrete PY - 2017 DO - https://doi.org/10.1002/suco.201600173 SN - 1464-4177 SN - 1751-7648 VL - 18 IS - 4 SP - 528 EP - 538 PB - Ernst & Sohn AN - OPUS4-42574 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig A1 - Powierza, Bartosz A1 - Weise, Frank A1 - Oesch, Tyler A1 - Dlugosch, R. A1 - Meng, Birgit T1 - Analysis of moisture transport in unilateral-heated dense high-strength concrete N2 - Unilateral thermal exposure of concrete building components induces moisture transport processes that have a significant influence on the spalling behaviour of dense high-strength concrete (HSC). These transport processes are based on evaporation and condensation mechanisms of liquid and gaseous water in the pores as well as the chemically bound water within the concrete. The low permeability of HSC and the formation of a saturated zone within building components (also known as a moisture clog) leads to high water-vapour pressures, which contributes to explosive spalling. The formation of these pressures has already been verified by means of pore-pressure measurement techniques. In addition, the redistribution of the moisture within concrete specimens subject to unilateral thermal exposure has been demonstrated on fractured surfaces. Investigations by means of the nuclear magnetic resonance (NMR) relaxometry technique and neutron radiography have shown one-dimensional changes in moisture distribution during thermal exposure. However, none of these methods has been able to depict the moisture distribution in three dimensions (3D), so the link between pore size, concrete micro-structure and moisture content is missing. The research project presented in this paper aims to fill this gap by developing a new multi-level test methodology to characterise non-destructively the temporal course of spatial moisture distribution during unilateral thermal exposure. The procedure used during this programme included the collection of X-ray 3D-computed tomography (CT) measurements using a miniaturised specimen subjected to in-situ thermal exposure and the comparison of those CT results with the results of one-dimensional NMR-relaxometry before and after the heating process. In the first step, a mobile heating device was developed, built and tested. To simulate a unilaterally-heated construction component, a cylindrical specimen made of HSC (Ø = 40 mm, L = 100 mm) was cast into an impermeable glass ceramic shell. The ceramic shell ensured a one-dimensional moisture flux and limited the thermal expansion of the concrete. An additional high-temperature wool (HTW) insulating shell ensured a one-dimensional heat flux. The heating device, which operated using infrared radiation (IR), allowed the unilateral heating of the specimens up to 300 °C using variable heating regimes. In the second step, the mobile heating device was integrated into the CT-scanner, which enabled the collection of measurements before, during and after heating. By subtraction of successive 3D-CT images, X-ray attenuation differences could be resolved three-dimensionally in the specimen and interpreted as changes in the moisture content. Initial results show that this test methodology can monitor the 3D changes of moisture content inside the specimen during thermal exposure. It enables the researcher to visualise areas with moisture accumulation as well as dehydrated areas inside the specimen. Comparative one-dimensional NMR-relaxometry measurements confirm the results of the CT image analysis. T2 - 5th International Workshop on Concrete Spalling due to Fire Exposure CY - Boras, Sweden DA - 12.10.2017 KW - Spalling KW - Fire KW - Moisture clog KW - Moisture transport KW - HPC KW - HSC KW - X-ray CT KW - NMR KW - NDT PY - 2017 SN - 0284-5172 SP - 227 EP - 239 AN - OPUS4-42983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Meng, Birgit A1 - Weise, Frank A1 - Voland, K. A1 - Krütt, Enno T1 - Ermüdungsbedingte Degradation und ihre Auswirkungen auf den Stofftransport in Fahrbahndeckenbeton N2 - Im Rahmen des Beitrags soll aufgezeigt werden, welchen Einfluss eine mechanisch induzierte Vorschädigung (Ermüdungsbeanspruchung) auf den Ablauf und die Intensität des AKR-Schädigungsprozesses hat. Dies erfordert eine ausführliche Beschreibung der vielfältigen interagierenden Schädigungs- und Transportprozesse und aufbauend eine enge Verknüpfung von Experimenten mit einer mehrskaligen Modellierung. Die experimentelle Basis bildete die mechanische Vorschädigung (Ermüdungsbeansprochung) großformatiger Balken aus einem Fahrbahndeckenbeton bei Einsatz alkaliempfindlicher Gesteinskörnungen. Aus diesen großformatigen Balken wurden nach erfolgter Ermüdungsbeanspruchung kleinformatige Probekörper gewonnen. An diesen wurde detailliert untersucht wie sich die mechanische Vorschädigung auf das Betongefüge und die daraus resultierenden Transport- und Schädigungsprozesse auswirkt. Von der mechanisch induzierten Vorschädigung bis zum AKR Schädigungsprozess sollten in diesem Kontext die Rissbildungsprozesse und der interagierende Eintrag bzw. die Auslaugung der Alkalien ganzheitlich betrachtet werden. Der Beitrag fokussiert auf die Charakterisierung der infolge der mechanischen Vorschädigung induzierten Rissbildungsprozesse. Ferner wird detailliert auf die Auswirkungen der mechanischen Rissbildung auf den Stofftransport eingegangen. KW - Baustoffe KW - Beton KW - Dauerhaftigkeit KW - Ermüdung KW - Alkali-Kieselsäure-Reaktion KW - AKR PY - 2017 SN - 978-3-00-056692-9 SP - 416 EP - 427 CY - Bochum AN - OPUS4-42970 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Simon, Sebastian A1 - Meng, Birgit T1 - Internal sulfate resistance of concrete N2 - If the amount of sulfate within the mix design for concrete is not balanced, ettringite formation which first controls solidification continues while the concrete is hardening. Ettringite forms by reaction of sulfate contained in the cement or in some admixture with calcium aluminate (C3A) as cement component. The “late primary ettringite formation” promotes an increase in volume within the hardened concrete leading to cracks. To analyze the effect of substituting part of ordinary Portland cement (OPC) by a treated brown coal fly ash mortar bars were tested according to ASTM C452. This test method was originally developed to extrapolate from the internal to external sulfate attack and is based on the idea that by testing a concrete mixture containing sulfate the process of deterioration is accelerated because it does not have to diffuse into the concrete before reaction first. In addition to the samples prescribed in ASTM C452 further samples in the size of the German SVA procedure were tested also designed for accessing the external sulfate resistance. The results show that while the replacement of 25 % of cement by brown coal fly ash leads to length changes around the limit defined by ASTM, the substitution of 50 % cement exceeded the limit by a multiple. The progress of expansion is the very similar for the two geometries tested. In-situ XRD measurements confirmed that while for pastes made of OPC the formation of ettringite is completed after 20 hours, this is not true for the mixtures containing the brown coal fly ash. In a different study the effect of hydrothermal treatment on the phase composition of ultra-high-performance concrete was analyzed. The results show that the sulfate and aluminate resulting from the decomposition of ettringite are bound into new phases. If this binding is permanent this might allow the larger use of sulfate bearing raw materials. T2 - EuroCoalAsh 2021 Conference CY - Online meeting DA - 02.11.2021 KW - Brown coal fly ash KW - Ettringite KW - Internal sulfate resistance KW - Test methods KW - In-situ XRD KW - Hydrothermal treatment PY - 2021 SP - 131 EP - 137 CY - Thessaloniki AN - OPUS4-54133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Meng, Birgit A1 - Müller, Urs A1 - Rübner, Katrin ED - Maierhofer, C. ED - Reinhardt, H.-W. ED - Dobmann, G. T1 - Components in concrete and their impact on quality: an overview KW - Concrete KW - Cement KW - Aggregate KW - Microstructure KW - Durability PY - 2010 SN - 978-1-84569-560-6 VL - 1 IS - Chapter 5 SP - 82 EP - 93 PB - Woodhead Publishing Ltd CY - Oxford AN - OPUS4-21049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Huismann, Sven A1 - Weise, Frank A1 - Meng, Birgit A1 - Schneider, U. ED - Kodur, V. ED - Franssen, J.-M. T1 - Influence of polypropylene fibres on the thermal strain of high strength concrete at high temperatures T2 - 6th International conference "Structures in fire" CY - East Lansing, Michigan, USA DA - 2010-06-02 KW - High performance concrete KW - High temperatures KW - Polypropylene fibres KW - Thermal strain KW - Acoustic emission KW - Ultrasound PY - 2010 SN - 978-1-60595-027-3 SP - 719 EP - 726 PB - DEStech Publications, Inc. CY - Lancaster, PA, USA AN - OPUS4-21563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Vasilic, Ksenija A1 - Roussel, N. A1 - Meng, Birgit A1 - Kühne, Hans-Carsten ED - Khayat, K.H. ED - Feys, D. T1 - Computational modeling of SCC flow through reinforced sections N2 - Computational modeling of fresh SCC flow is a comprehensive and time consuming task. The computational time is additionally increased when simulating casting of reinforced sections, where each single reinforcement bar has to be modeled. In order to deal with this issue and to decrease the computational time, an innovative approach of treating a reinforcement network as a porous medium is applied. This contribution presents the model for concrete flow through reinforced sections, based on Computational Fluid Dynamics (CFD), coupling a single-phase flow model for SCC and a continuum macroscopic model for porous medium. In the last part of this paper, numerical simulations are compared with experimental results obtained on model fluids. T2 - SCC2010 - Design, production and placement of self-consolidating concrete CY - Montreal, Canada DA - 2010-09-26 PY - 2010 SN - 978-90-481-9663-0 DO - https://doi.org/10.1007/978-90-481-9664-7_16 N1 - Serientitel: RILEM bookseries – Series title: RILEM bookseries VL - 1 IS - 5 SP - 187 EP - 195 PB - Springer AN - OPUS4-22277 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Littmann, K. T1 - Parameterstudien zum Einfluss von Rezepturveränderungen auf Schwindverhalten, Rissneigung und Steifigkeit mineralischer Instandsetzungsmörtel T2 - 7. Internationales Kolloquium Industrieböden 2010 CY - Ostfildern, Deutschland DA - 2010-12-14 KW - Betoninstandsetzung KW - Instandsetzungsmörtel KW - Modulare Systeme KW - Haftverbund KW - SPCC KW - PCC PY - 2010 SN - 3-924813-85-X IS - Kap. 2.6 SP - 191 EP - 200 AN - OPUS4-22845 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit T1 - Development of a modular system for the protection and repair of concrete structures KW - Repair mortar KW - Repair systems KW - Polymer cement concrete (PCC) KW - Sprayed polymer cement concrete (SPCC) PY - 2010 SN - 1864-7251 SN - 0947-4498 VL - 16 IS - 4/5 SP - 387 EP - 400 PB - Aedificatio Publ. CY - Freiburg AN - OPUS4-22773 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Herbst, Tristan A1 - Hauer, B. A1 - Rübner, Katrin A1 - Meng, Birgit ED - Teipel, U. T1 - Wege zur Bewertung der Einsatzmöglichkeit sekundärer Gesteinskörnungen in Beton T2 - Symposium Rohstoffeffizienz und Rohstoffinnovationen CY - Nürnberg, Deutschland DA - 2010-02-04 KW - Gesteinskörnung KW - Beton KW - Nachhaltigkeit KW - Bewertung KW - Einsatzpotenzial PY - 2010 SN - 978-3-8396-0097-9 SP - 171 EP - 191 PB - Fraunhofer IRB Verl. AN - OPUS4-22952 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Herbst, Tristan A1 - Hauer, B. A1 - Rübner, Katrin A1 - Meng, Birgit T1 - Einsatzpotentzial und nachhaltige Verwertung von Hausmüllverbrennungsaschen als Gesteinskörnungen im Beton T2 - GDCh-Fachtagung Bauchemie 2009 CY - Freiberg, Deutschland DA - 2009-10-08 KW - Sekundärrohstoffe KW - Müllverbrennungsaschen KW - Sekundäre Gesteinskörnung PY - 2009 SN - 978-3-936028-61-4 VL - 41 SP - 237 EP - 240 AN - OPUS4-22951 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kargol, Marta A1 - Müller, Urs A1 - Gardei, André A1 - Meng, Birgit T1 - Influence of blended cements on the performance of water repellent agents N2 - Ingress of moisture and harmful ions (e.g. Chloride, sulfate) into cementitious materials is one of the major factors in defining their durability. Modifications of building materials by targeted deposition of surface functional agents that make the surface hydro- and/or oleophobic aim to minimize moisture and ion ingress, and thus extend Service life of the cement based structures. Water repellent and easy-to-clean coatings for inorganic Substrates have gained strong attention during the last few years and various formulations based on silicones or alkylpolysiloxanes have been developed. Cementitious building materials are highly complex Systems with many components and changing properties in the course of a building’s Service life. The interactions between the Chemical agents and the cement based materials depend on many factors. The Chemical properties of the material Substrate appear to be the most important but in the context of their influence on the functionality of silanes and/or siloxanes these characteristics have not been well understood yet. The aim of this study was to evaluate the effect of different blended cements on water repellent agents’ performance. Two organosilicon compounds were applied on fresh blended cements containing limestone (L), fly ash (F), slag (S) and trass (T), and investigated in terms of their functionality. The surface properties of functionalized blended cements were studied based on wettability, i.e. contact angle measurements, before and after exposure to artificial and natural weathering. The first results indicate that slag and trass more distinctly affect the water repellent Surface performance after aging. T2 - Hydrophobe VI - 6th International conference on water repellent treatment of building materials CY - Rome, Italy DA - 12.05.2011 KW - Hydrophobic surfaces KW - Wettability KW - Impregnation KW - Blended cement KW - Silanes PY - 2011 SN - 978-3-931681-99-9 SP - 23 EP - 32 PB - Aedificatio Publishers AN - OPUS4-23681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit T1 - Einfluss ausgewählter Modifikationen der Mischungszusammensetzung auf die Eigenschaften von Instandsetzungsmörteln N2 - Trotz der zahlreichen Möglichkeiten zur Beeinflussung der Mörteleigenschaften durch Mischungsmodifikationen ist es nahezu unmöglich, einzelne Eigenschaften unabhängig von anderen zu verändern. Bei einer Mischungsoptimierung muss im Einzelfall immer entschieden werden, welcher der gewünschten Eigenschaften die höchste Priorität zukommt. Anhand von Parameterstudien wird im vorliegenden Artikel verdeutlicht, wie es für bestimmte Anwendungen sinnvoll sein kann, die Verschlechterung einzelner Eigenschaften zu akzeptieren, wenn dadurch eine für den speziellen Einsatzfall essenzielle Eigenschaft verbessert werden kann. Die komplexen Wechselwirkungen der einzelnen Bestandteile fuhren dazu, dass auch scheinbar widersprüchliche Kombinationen von Zusatzmitteln im Einzelfall erforderlich werden können. Zur Anpassung der meisten Mörteleigenschaften gibt es verschiedene Möglichkeiten der Zielerreichung mit jeweils unterschiedlichen Nebeneffekten. Frisch- und Festmörteleigenschaften sind dabei gleichermaßen zu beachten. KW - Instandsetzungsmörtel KW - Betoninstandsetzung KW - Instandsetzungssysteme KW - Polymer-Zement Beton (PCC) KW - Polymer-Zement Spritzbeton (SPCC) KW - Repair mortar KW - Concrete rehabilitation KW - Repair systems KW - Polymer cement concrete (PCC) KW - Sprayed polymer cement concrete (SPCC) PY - 2011 SN - 1864-7251 SN - 0947-4498 VL - 17 IS - 3/4 SP - 169 EP - 180 PB - Aedificatio Publ. CY - Freiburg AN - OPUS4-24479 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit T1 - Repair mortars for the restoration and reprofiling of natural stone elements in cultural heritage N2 - For the protection of the world's cultural heritage the restoration of listed buildings and monuments is an important task. In many cases the need to repair and reprofile natural stone elements occurs. Repair mortars for such applications have to match historicocultural interests as well as durability related and constructive interests. Currently a research project dealing with the development and optimisation of such mortars is set up at the BAM. Special focus is laid on the possibility of a modular adaption to match a vast variety of stone properties. Besides the development and lab scale testing of the mortar system, an in-situ application will be planned and executed. T2 - EWCHP-2011 - European workshop on cultural heritage preservation CY - Berlin, Germany DA - 26.09.2011 KW - Repair mortar KW - Natural stone KW - Stone restoration KW - Stone reprofiling KW - Modular system KW - Listed buildings and monuments PY - 2011 SN - 978-3-8167-8560-6 SP - 281 EP - 288 AN - OPUS4-24561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herbst, Tristan A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. T1 - Assessment concept for the sustainable use of secondary aggregates in concrete N2 - Nowadays there are several applications of mineral recycling materials and residues. At present an assessment method for the use of secondary raw materials, which considers sustainability aspects, does not exist. In the framework of the German DAfStb/BMBF research project 'Sustainable Building with Concrete' an assessment concept was developed. It includes the following four assessment steps: I. Basic considerations, II. Advantages for sustainable construction, III. Alternative paths for application, and IV. Sensitivity analysis. The concept was developed on the basis of recycled concrete aggregates, which are already used according to German standards. Afterwards, it was applied and verified by the evaluation of the utilisation of municipal solid waste incinerator bottom ashes. T2 - International RILEM conference on advances in construction materials through science and engineering CY - Hong Kong, China DA - 05.09.2011 KW - Sustainability KW - Assessment KW - Secondary aggregates KW - Concrete PY - 2011 SN - 978-2-35158-116-2 VL - PRO 79 IS - Chapter 10 / Study of sustainable use... SP - 1 EP - 8 PB - RILEM Publications AN - OPUS4-24564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schießl, P. A1 - Meng, Birgit A1 - Adam, G. A1 - Rößler, G. A1 - Schröder, P. A1 - Schwamborn, B. A1 - Wallner, B. A1 - Wiegrink, K. ED - Zilch, K. ED - Diederichs, C. J. T1 - Baustoffe PY - 2002 SN - 3-540-65760-6 IS - Kap. 3.1 SP - 3-3-3-60 PB - Springer CY - Berlin AN - OPUS4-2070 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kühne, Hans-Carsten A1 - Maultzsch, Matthias A1 - Wolff, L. A1 - Meng, Birgit A1 - Raupach, M. ED - Maultzsch, M. T1 - Long-term performance of surface protection systems for concrete T2 - 11th International Congress on Polymers in Concrete (ICPIC `04) CY - Berlin, Germany DA - 2004-06-02 KW - Surface protection system KW - Concrete KW - Weathering KW - Water uptake KW - Freezethaw resistance KW - Chloride ingress KW - Carbonation KW - Hydrophobic treatment PY - 2004 SN - 3-00-013706-8 SP - 417 EP - 428 PB - BAM CY - Berlin AN - OPUS4-3602 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bahlmann, Stefanie A1 - Rübner, Katrin A1 - Meng, Birgit T1 - Untersuchungen zur Verwertung industrieller Reststoffe als Primärrohstoffsubstitut in Mörtel und Beton T2 - GDCh-Fachtagung Bauchemie CY - Siegen, Deutschland DA - 2007-09-27 KW - Verwertungspotential KW - Industrielle Reststoffe KW - Filterrückstand KW - Papierasche KW - Biomasseasche KW - Edelstahlschlacke KW - Zumahlstoff KW - Betonzusatzstoff PY - 2007 SN - 3-936028-50-8 N1 - Geburtsname von Bahlmann, Stefanie: Ramolla, S. - Birth name of Bahlmann, Stefanie: Ramolla, S. VL - 37 SP - 237 EP - 244 AN - OPUS4-16095 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Nanotechnologische Anwendungen im Baustoffbereich T2 - Branchendialog "Nanotechnologie in der Bauwirtschaft" Bundesmininsterium f. Wirtschaft u. Technologie CY - Berlin, Germany DA - 2007-11-02 PY - 2007 AN - OPUS4-16172 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - Pirskawetz, Stephan A1 - Müller, Urs A1 - Meng, Birgit T1 - Charakterisierung der Schädigungsprozesse in Betonen mit innovativen Prüftechniken KW - Beton KW - Naturstein KW - Schadensanalyse KW - Innovative Prüftechnik PY - 2007 IS - 13 SP - 14 EP - 20 AN - OPUS4-15715 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Weise, Frank A1 - Meng, Birgit ED - Jürgen Berger, ED - Fischer, Andreas ED - Stefan Himburg, ED - Michael Kramp, T1 - Einsatz innovativer Verfahren der Bauwerksdiagnose für die Bestandserfassung - ausgewählte Fallbeispiele T2 - Berliner Hoch- und Ingenieurbaukolloquium BHIK 07 "Bauen im Bestand - Innovationen aus Wissenschaft und Praxis" CY - Berlin, Deutschland DA - 2007-11-23 KW - Bauwerksdiagnose KW - Zerstörungsfreie Prüfung KW - Radar KW - Ultraschall KW - Röntgen-Computertomografie PY - 2007 SN - 978-3-8322-6723-0 SN - 0945-067X SP - 27 EP - 46 PB - Shaker CY - Aachen AN - OPUS4-16325 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Einsatz innovativer Verfahren der Bauwerksdiagnose für die Bestandserfassung - ausgewählte Beispiele T2 - Berliner Hoch- und Ingenieurbaukolloquium BHK 07 "Bauen im Bestand" CY - Berlin, Germany DA - 2007-11-23 PY - 2007 AN - OPUS4-16443 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Meng, Birgit A1 - Fontana, Patrick A1 - Müller, Urs T1 - Nanotechnologie im Beton - Entwicklungsstand und Innovationschancen KW - Nanotechnologie KW - Analytik KW - Gefüge KW - Zement KW - Beton PY - 2008 SN - 978-3-7625-3624-6 VL - 56 SP - 186 EP - 190 PB - Bauverlag BV CY - Gütersloh AN - OPUS4-16316 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Urs A1 - Meng, Birgit A1 - Kühne, Hans-Carsten A1 - Nemecek, J. A1 - Fontana, Patrick ED - E. Fehling, ED - Schmidt, M. ED - S. Stürwald, T1 - Micro texture and mechanical properties of heat treated and autoclaved Ultra High Performance Concrete (UHPC) KW - Ultra high performance concrete KW - Micro texture KW - Mechanical strength KW - Secondary cemetitious materials PY - 2008 SN - 978-3-89958-376-2 IS - 10 SP - 213 EP - 220 CY - Kassel AN - OPUS4-16726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brockmann, T. A1 - Fontana, Patrick A1 - Meng, Birgit A1 - Müller, Urs T1 - Nanotechnologie im Bauwesen N2 - Zu den Zielen der Nanotechnologie gehört die Entwicklung, Produktion und Anwendung von Materialien und Werkstoffen mit völlig neuartigen Leistungsspektren. Für die Baupraxis und die Materialforschung lassen sich über den Einsatz der Nanotechnologie Ziele wie die Optimierung von Baustoffeigenschaften, Vermeidung von Schäden und neue Funktionalitäten definieren. Der vorliegende Beitrag gibt einen Überblick über mögliche Anwendungsbereiche der Nanotechnologie im Bausektor, wie z. B. zementgebundene Baustoffe, Außen- und Dachfassaden, Fenster und Verglasungen, Brandschutz, Inneneinrichtung und Infrastrukturbau. Zudem werden aktuelle Forschungsarbeiten mit nanowissenschaftlichem und nanotechnologischem Schwerpunkt im Bereich baustoffbezogener Materialien der Bundesanstalt für Materialforschung und -prüfung (BAM) in Berlin vorgestellt. Die Forschungstätigkeiten beziehen sich zum einen auf die Modifikation der Hydratphasen in Ultra-Hochleistungsbeton (UHPC) und zum anderen auf die Weiterentwicklung von Anti-Graffiti-Systemen. KW - Nanotechnologie KW - Forschung und Entwicklung KW - UHPC KW - Anti-Graffiti PY - 2008 DO - https://doi.org/10.1002/best.200800624 SN - 0005-9900 SN - 1437-1006 VL - 103 IS - 7 SP - 446 EP - 454 PB - Ernst CY - Berlin AN - OPUS4-17731 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Urs A1 - Meng, Birgit A1 - Fontana, Patrick T1 - Nano-Gefügeanalytik - Die Optimierung von Baustoffen KW - Nanotechnologie KW - Baustoffe PY - 2008 SN - 1618-7881 VL - 1 IS - 1 SP - 18 EP - 21 PB - GIT Verl. CY - Darmstadt AN - OPUS4-17438 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Mikrostruktur und Dauerhaftigkeit zementgebundener Baustoffe T2 - 8. Münchener Baustoffseminar "Dauerhaftigkeit von Betonkonstruktionen - Von den Mechanismen zum Lebensdauermanagement" CY - Munich, Germany DA - 2008-10-10 PY - 2008 AN - OPUS4-18201 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Herbst, Tristan A1 - Meng, Birgit T1 - Ganzheitliche Eignungsbewertung potenzieller Recyclingwege für Mauerwerksrestmassen PY - 2013 SN - 978-3-433-03017-2 SN - 978-3-433-60296-6 SN - 0170-4958 VL - 38 IS - Kap. 2.2.6 SP - 637 EP - 641 PB - Ernst & Sohn AN - OPUS4-28564 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meng, Birgit A1 - Müller, Urs A1 - Garcia, O. A1 - Malaga, Katarina T1 - Performance of a new anti-graffiti agent used for immovable cultural heritage objects N2 - Cultural Heritage objects are in many cases invaluable and irrecoverable, therefore their protection is a prior goal. One threat arises by intentionally defacing such objects with graffiti. One possibility to face the imminent threat is the application of a surface protection in form of anti-graffiti systems (AGS). However, the knowledge about the performance and durability of AGS on substrates used for historical buildings is still fragmented. The goal of the presented study was to investigate the performance of a newly developed agent in comparison to a selection of commercial anti-graffiti agents on different substrates, which were used for historical buildings. Four commercial anti-graffiti agents with different chemical formulations were selected and tested with the new agent on different stone and brick substrates. The results showed clearly that AGS based on dense, water vapour impermeable coatings are not suitable to porous substrates such as sandstone, brick or porous limestone due to their impair of the hygric properties and the visual appearance of a substrate. The new agent could not completely reach the cleaning efficacy of the dense coatings but exhibited a much lower impact on the properties of the substrate and was therefore better compatible to historical surfaces. KW - Graffiti KW - Cultural Heritage KW - Anti-graffiti agent KW - Performance KW - Stone KW - Brick KW - Cleaning efficacy KW - Compatibility PY - 2014 DO - https://doi.org/10.1080/15583058.2012.747116 SN - 1558-3058 SN - 1558-3066 VL - 8 IS - 6 SP - 820 EP - 834 PB - Taylor & Francis CY - Philadelphia, Pa., USA AN - OPUS4-28605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Vermeidung stofflicher Probleme bei der Wärmebehandlung von Beton T2 - BMO-Fachtagung "Beton für alle Wetter", BAM CY - Berlin, Germany DA - 2012-11-22 PY - 2012 AN - OPUS4-27110 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pistol, Klaus A1 - Weise, Frank A1 - Meng, Birgit ED - Roussel, N. ED - Bessaies-Bey, H. T1 - High temperature behaviour of self-compacting concrete with limestone powder N2 - Although concrete in general is a non-combustible material, the fire resistance of concrete structures depends, to a large extent, on the mechanical material behaviour. Fire tests have shown that SCC is often susceptible to explosive spalling due to fire exposure, in a similar manner to HPC. But there are hardly any studies available that report properties of specimens at high temperatures. T2 - 7th RILEM International conference on self-compacting concrete and of the 1st RILEM international conference on rheology and processing of construction materials CY - Paris, France DA - 02.09.2013 KW - Fire resistance KW - Stress-strain-relation KW - Compressive strenght KW - Polypropylene fibres KW - Self-compacting concrete KW - Thermo mechanical behaviour KW - Fire safety design PY - 2013 SN - 978-2-35158-137-7 SN - 978-2-35158-138-4 SP - 221 EP - 228 PB - RILEM Publications CY - Bagneux, France AN - OPUS4-29985 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Fontana, Patrick A1 - Pirskawetz, Stephan A1 - Weise, Frank A1 - Meng, Birgit ED - Nothnagel, R. ED - Twelmeier, H. T1 - Zwangsinduzierte Rissbildung in Hochleistungsbeton durch autogenes Schwinden N2 - In diesem Beitrag werden Untersuchungsergebnisse vorgestellt, die den Einfluss von Mikrosilica auf die Selbstaustrocknung und das damit verbundene autogene Schwinden der Bindemittelmatrix von Hochleistungsbetonen beschreiben. Die dadurch hervorgerufenen Schädigungsprozesse wurden mit Hilfe von zerstörungsfreien Prüfmethoden verfolgt. Dabei zeigte sich, dass eine durch äußeren Zwang bedingte Mikrorissbildung durch Schallemissionsanalyse detektiert werden kann. KW - Beton KW - Verformung KW - Rissbildung KW - Zusatzstoffe PY - 2013 SN - 978-3-642-29573-7 DO - https://doi.org/10.1007/978-3-642-29573-7_34 SP - 343 EP - 350 PB - Springer CY - Berlin Heidelberg AN - OPUS4-31758 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Ausmaß von Vorschädigungen, Transportprozesse in vorgeschädigtem Betongefüge T2 - AKR unter kombinierter Einwirkung CY - Weimar, Deutschland DA - 2014-10-21 PY - 2014 AN - OPUS4-31705 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pistol, Klaus A1 - Weise, Frank A1 - Meng, Birgit A1 - Diederichs, U. T1 - Polypropylene fibres and micro cracking in fire exposed concrete N2 - Though, concrete in general is a non-combustible building material, modern High Performance Concrete (HPC) is very susceptible to violent explosive spalling during a fire attack. This requires protective measures for fire safety design of concrete structures. The current most worthwhile method to prevent explosive spalling is the addition of monofilament Polypropylene fibres (PP-fibres). However, since it has become common knowledge that PP-fibres are suitable for fire safety design, a variety of theories concerning the mode of action of PP-fibres have been suggested. The present article summarizes the most important hypothesis and presents an innovative method for the analysis of micro structural processes in heated specimens. The results show that due to the thermal decomposition of PP-fibres capillary channels are created. Simultaneously, a netlike micro crack formation occurs, which connects these capillary channels. This enables the relief of internal stresses (mechanical effect) and the formation of a permeable transport system for the escaping water vapour (permeation effect). KW - Concrete KW - Fire Spalling KW - Micro-Crack KW - Polypropylene Fibres PY - 2014 DO - https://doi.org/10.4028/www.scientific.net/AMR.897.284 SN - 1022-6680 SN - 1662-8985 VL - 897 SP - 284 EP - 289 PB - Trans Tech Publ. CY - Zurich AN - OPUS4-30383 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krütt, Enno A1 - Weise, Frank A1 - Meng, Birgit ED - Ye, G. ED - Yuan, Y. ED - Romero Rodriguez, C. ED - Zhang, H. ED - Savija, B. T1 - Fatigue induced degradation in pavement concrete and its effect on the alkali-silica reaction N2 - In recent years the German motorway network has seen an increase in the occurrence of damage to concrete road surfaces that can be attributed to the alkali-silica reaction (ASR). In view of the often drastically reduced service life of road surfaces due to ASR, research activity in this field has notably increased. Alongside preventative measures in concrete technology i.e. the usage of low-alkali cements, the main research focus up to now has been on the development of performance-oriented testing procedures for ASR prevention. The effects of mechanicallyinduced damage resulting from cyclic traffic and climatic loading have previously not been taken into consideration. The assessment of the myriad degradation and transport processes necessary for an understanding of these effects requires close interaction between experiments and corresponding multi-scale models. This contribution is focused on the experiments utilizing innovative testing techniques. The research is founded on a series of fatigue tests performed on large-scale beams with simultaneous tracking of the degradation process using non-destructive evaluation methods. Subsequently, smaller test specimens were extracted from the predamaged beams for further experiments. These experiments included investigation of the influence of fatigue-induced cracks on moisture and alkali transport. Subsequent storage of the small-scale test specimens, with and without cyclic pre-damage, in an ASR-conducive environment then provided initial findings on the influence of fatigue-induced degradation on the ASR. The results show that the degradation process can be well observed with the test Setup developed for the fatigue experiments. Further, a small but noticeable increase of mass Transport due to fatigue-induced degradation was measured, which correspondingly indicated an increased ASR damage potential. T2 - 4th International Conference on Service Life Design for Infrastructures (SLD4) CY - Delft, The Netherlands DA - 27.08.2018 KW - Fatigue KW - Pavement KW - ASR KW - Concrete PY - 2018 SN - 978-2-35158-213-8 SP - 112 EP - 121 PB - RILEM Publication S.A.R.L. CY - Paris, France AN - OPUS4-46197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, L. A1 - Fontana, P. A1 - Qvaesching, D. A1 - Kreft, O. A1 - Hoppe, Johannes A1 - Meng, Birgit T1 - UHPC-AAC facade elements: Structural design, production technology and mechanical behavior N2 - The aim of this study was to develop a lightweight composite facade element for new buildings and for the refurbishment of existing facades. These composite elements have been developed combining an insulation layer of autoclaved aerated concrete (AAC) with an external ultrahighperformance concrete (UHPC) supporting layer. This solution allows avoiding the use of connectors and facilitates the production procedure. The structural behavior of the facade elements is mainly influenced by the presence of the upturning edges that are able to increase the stiffness of the element and reduce the thickness of the external layer. The insulation material has no influence on the structural behavior of the UHPC boxes. Flexural tests were carried out to investigate a potential detachment of the external layer from the upturning edge. The photogrammetric Analysis used during the flexural tests essentially confirmed that the bond between the two UHPC layers cast in two steps is reliable. The quality of the bond between the external layer and the upturning edge is a key parameter to define the bearing capacity of the element. T2 - ICAAC 6th International Conference on Autoclaved Aerated Concrete CY - Potsdam, Germany DA - 04.09.2018 KW - Autoclaved aerated concrete KW - Flexural testing KW - Photogrammetric analysis KW - Production technology KW - Ultrahigh-performance concrete PY - 2018 SN - 978-3-433-03276-3 DO - https://doi.org/10.1002/cepa.854 VL - 2 IS - 4 SP - 483 EP - 488 PB - Wilhelm Ernst & Sohn - Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin, Germany AN - OPUS4-47588 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krütt, Enno A1 - Pirskawetz, Stephan A1 - Wallau, Wilma A1 - Meng, Birgit T1 - Development of an automated 60 °C Concrete Prism Test N2 - ln most of the ASR-test procedures, the expansion of concrete or mortar specimens is used as an indicator to assess the ASR-potential of an aggregate or a specific concrete mix. For these tests, the specimens are stored in an ASR-provoking environment, where the reaction is accelerated by elevated temperature and humidity. To measure the length change, the storage must be interrupted for at least a few minutes. Düring the 60 °C Concrete Prism Test (60 °C-CPT), the specimens are cooled down to 20 °C for 24 hours, to ensure the same hygrothermal conditions for every measurement. This limits the number of measurements during the test period and may lead to additional effects, that probably influence the expansion development. With a recently developed device, it is possible to continuously monitor the expansion ofprisms without interrupting the ASR-provoking storage. Due to the dense database of this automated test, the results can contribute to a better understanding of the ASR-process. This study compares results of the automated and conventional 60 °C-CPT. Tests of different aggregates showed, that the results of the automated and conventional test are consistent, but the expansions during the conventional test are generally higher. Preliminary results led to the conclusion, that the cooling for the measurements leads to additional expansions. Therefore, a modified threshold should be discussed for the automated 60 °C-CPT. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisboa, Portugal DA - 31.05.2022 KW - 60 °C-CPT KW - ASR expansion monitoring KW - Automated testing PY - 2021 SN - 978-972-49-2315-4 VL - 1 SP - 789 EP - 799 AN - OPUS4-54553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Betondesign digital - Potenziale für das Bauwesen N2 - Beton ist weltweit einer der wichtigsten Konstruktionswerkstoffe und zeichnet sich durch eine enorme Anpassungsfähigkeit an sich verändernde Anforderungen aus. Damit verbunden ist eine hohe und kontinuierlich zunehmende Komplexität hinsichtlich der Ausgangsstoffe, Rezepturen und des Herstellungsprozesses. Folglich setzt eine Ausschöpfung des technischen und umweltbezogenen Potenzials der Betonbauweise höchste Expertise bei den Einzelakteuren der Bauindustrie voraus. T2 - MatFo2022 „Vom Material zur Innovation: Digital, Neutral, Vital“ CY - Cologne, Germany DA - 14.11.2022 KW - Beton KW - Zement KW - Digitalisierung KW - Ontologien PY - 2022 UR - https://www.werkstofftechnologien.de/veranstaltungen/matfo2022-vom-material-zur-innovation-digital-neutral-vital AN - OPUS4-59140 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Bilgin, S. A1 - Hoppe, Johannes A1 - Fontana, P. A1 - Meng, Birgit ED - Middendorf, B. ED - Fehling, E. ED - Wetzel, A. T1 - Composite UHPC facade elements with self-cleaning surface: Aspects of technological manufacturing N2 - In the framework of the European collaborative project H-House, which was finished in 2017, large façade elements were developed consisting of a box shaped external shell of ultra-high-performance concrete (UHPC) with a functionalized surface and an insulation of autoclaved aerated concrete (AAC). The exposed concrete of the elements was further refined by adding self-cleaning properties to the surface through imprinting a microstructure in combination with chemical agents directly in the casting process. The paper focuses on selected technological aspects of the manufacturing process of large-scale prototypes. Presented are results of the upscaling process of functionalized surfaces from small specimen up to large UHPC composite facade elements produced for the construction of a demonstrator. T2 - 5th International Symposium on Ultra-High Performance Concrete and High Performance Construction Materials (HiPerMat 2020) CY - Kassel, Germany DA - 11.03.2020 KW - Ultra-High Performance Concrete KW - Facade Elements KW - Self-Cleaning Properties KW - Architectural Concrete PY - 2020 SN - 978-3-7376-0828-2 DO - https://doi.org/10.17170/kobra-202002271026 IS - 32 SP - 51 EP - 52 PB - kassel university press CY - Kassel AN - OPUS4-51908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giebson, C. A1 - Voland, Katja A1 - Ludwig, H.-M. A1 - Meng, Birgit T1 - Untersuchungen zur Alkali-Kieselsäure-Reaktion in vorgeschädigten Fahrbahndeckenbetonen N2 - In Betonbauteilen unter gleichzeitiger zyklischer Beanspruchung und externer Alkalizufuhr ist die Gefahr von Schäden infolge oder unter Mitwirkung einer Alkali-Kieselsäure-Reaktion (AKR) besonders hoch. Dies betrifft insbesondere Fahrbahndecken, bedingt durch den zunehmenden Schwerlastverkehr und den winterlichen Auftrag des Enteisungsmittels NaCl. Speziell die Rolle einer mechanischen Vorschädigung des Betons infolge der Verkehrsbeanspruchungen auf den Ablauf einer AKR ist dabei aber noch nicht in ausreichendem Umfang geklärt. Ein Teil der dazu seit 2012 durchgeführten Untersuchungen im Rahmen der DFG-Forschergruppe 1498 soll im Folgenden vorgestellt werden. Es zeigte sich, dass eine AKR in definiert mechanisch vorgeschädigten Betonprobekörpern mit alkalireaktiven Gesteinskörnungen und unter äußerer Alkalizufuhr vor allem früher beginnt als in äquivalenten Probekörpern ohne Vorschädigung. Grund dafür ist das schnellere und tiefere Eindringen von Wasser und insbesondere gelöstem NaCl in den Beton, wodurch Na-Ionen als Reaktionspartner für eine AKR früher und langfristig auch in größerer Menge verfügbar sind.------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ In concrete elements, simultaneously subjected to cyclic loadings and external alkalis, the risk for damages caused by or under participation of an alkali-silica reaction (ASR) is particularly high. This concerns especially concrete pavements due to the increasing heavy load traffic and the wintry application of NaCl deicer. Notably the role of a mechanical pre-damage of concrete caused by traffic loadings on the course of the ASR is largely unclear. A part of the investigations that has been conducted since 2012 into this issue within the scope of the DFG (German research foundation) funded research group 1498 shall be introduced in the following. It was evident that an ASR in defined mechanically pre-damaged concrete prisms with alkali-reactive aggregates and under an external supply of alkalis started earlier than in equal prisms without a pre-damage. The reason for this is the faster and deeper ingress of water and particularly of dissolved NaCl into the concrete, by what Na ions as reaction partner for an ASR are available earlier and, in the long-term, in greater amounts too. KW - Alkali-Kieselsäure-Reaktion KW - AKR KW - Äußere Alkalizufuhr KW - Fahrbahndeckenbetone KW - Mechanische Vorschädigung KW - Versuche KW - Korrosion KW - Baustoff PY - 2015 DO - https://doi.org/10.1002/best.201400094 SN - 0005-9900 SN - 1437-1006 VL - 110 IS - 1 SP - 13 EP - 21 PB - Ernst CY - Berlin AN - OPUS4-32431 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herbst, Tristan A1 - Meng, Birgit T1 - Concept for a holistic sustainability assessment of the end-of-life phase of masonry N2 - In Germany, a quantity of more than 10 million metric tons of masonry rubble is generated per year. With regard to a sustainable closed substance cycle waste management, these rest masses have to be recovered if possible. The end-of-life (EOL) phase of masonry includes the planning steps of demolition, processing and application. The choice of the most sustainable solution raises questions regarding material technology, plant engineering, economic efficiency and ecological issues. For this purpose, a methodological concept for a holistic assessment of the EOL phase of masonry is developed within the scope of a doctoral thesis. For the assessment the Cost-Effectiveness Analysis (CEA) is adapted. The assessment concept enables a holistic comparison of different EOL scenarios for masonry while integrating all planning steps. It combines Material Flow Analysis (MFA), Life Cycle Analysis (LCA), Life Cycle Working Environment (LCWE), economic evaluation methods and material testing. In future, various scenarios can be evaluated with regard to the goals of the European and German waste management industry. KW - sustainability KW - end-of-life phase KW - masonry PY - 2016 DO - https://doi.org/10.1144/SP416.5 SN - 0375-6440 SN - 0305-8719 SN - 2041-4927 VL - 416 IS - 1 SP - 47 EP - 57 CY - London AN - OPUS4-33166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Werner, Daniel A1 - Gardei, André A1 - Simon, Sebastian A1 - Meng, Birgit T1 - Microscopic investigation of building materials affected by alkali-silica reaction N2 - Concrete is the most applied building material in modern times. It is present in all kinds of structures and no other material secms to rcplace concrete as the most selected building material in the near future. The prime advantages are the high performance, the easy production and a facile processability. The sustainability and durability are important requirements to concrete. Even if concrete is significantly less susceptible against factors promoting a damage, compared to other materials, there are still mechanisms affecting it. In particular, high-ways and hydraulic structures made of concrete worldwide show cases of alkali-silica reaction (ASR) damages. This article refers to experience at BAM Federal InstituteforMaterials Research and Testing for several decades to ASR research and darnage assessment. ASR is a severe darnage mechanism that can occur in concrete, when certain conditions related to composition and cxposition arise in a critical combination. The chemical reaction is based on the alkalis and the silica in the concrete and was first identified by Stanton in highway structures in California (Stanton, 1940). Actually three components are needed to initiate ASR: alkali-sensitive siliceous aggregates, alkalis coming from internal (cement or other components) or external sources (de-icing salt or sea water) and water. If all of these components are sufficiently present an alkali-silica gel could be formed (Hobbs, 1988). This gel itself needs additional space when it is formed. Furthermore it is able to swell in the presence of humidity, both processes generating an expansion pressure inside the concrete. As a consequence of intensive expansion, cracks can occur, which significantly lowers thc strength of the material. Parameters like amount and chemical composition of the gel as weil as the pattern and width of cracks can help to classify the ASR darnage (Swamy, 1992). The objective of this article is to demoostrate the microscopic work on ASR affected concrete samples, carried out to assess the damaging process or to evaluate various alkali-sensitive aggregates. It will explain the approach of ASR investigation from the macroscale to microscale, starting briefly with the condition assessment, over treatment and investigations of samples in the laboratory, to the use of different microscopical and analytical techniques. In the main part the characteristic features for identifying ASR in concrete are presented by using microscopic images. Especially the emphasis lies on the role of the aggregate. T2 - 15th Euroseminar on microscopy applied to building materials CY - Delft, The Netherlands DA - 17.06.2015 KW - Alkali-silica reaction KW - Concrete KW - Damage analysis KW - Materials characterisation KW - Preparation of thin sections PY - 2015 SN - 978-94-6186-480-2 SP - 1 EP - 11 AN - OPUS4-33791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, C. A1 - Meng, Birgit A1 - Nemecek, J. ED - Ludwig, H.-M. T1 - Investigations on the process of autoclaving ultra-high performance concrete (UHPC) N2 - Concrete technology results more and more in the development of materiale with enhanced properties, such as high strength, higher durability and increased ecological compatibility. One exceptional example is Ultra-High Performance Concrete (UHPC). Its advantages are very high compressive strength and an improved durability, caused by their dense micro structure. Curing under water vapor Saturation pressure (autoclaving) can improve these properties by affecting the micro structure and better the mechanical properties of UHPC. Autoclaving leads to an enhanced cement hydration and accelerated reaction rate of supplementary cementitious materials (SCM) and mineral additions, Used at the production of aerated autoclaved concrete (AAC) and sand-lime bricks, the process of autoclaving is well known, especially in highly porous Systems. One well known requirement to autoclave effectively is a porosity of at least 10%. There is no sufficient heat transfer and also not enough water available if the porosity is lower, Nevertheless, autoclaving also works in the dense structure of UHPC with porosities lower than 2%, as former investigations have shown. There is only a visible difference between the outer parts of the samples compared to their core. Investigations on the chemistry, the micro structure as well as the mechanical properties where performed to find an explanation to this effect and to explain the functionality of autoclaving UHPC in spite of the low porosity. T2 - 19. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 16.09.2015 PY - 2015 SN - 978-3-00-050225-5 VL - 2 SP - P2.15, 2-1039 EP - 2-1044 AN - OPUS4-34872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Selleng, Christian A1 - Fontana, Patrick A1 - Meng, Birgit ED - Ludwig, H.-M. T1 - Einfluss der Dauer der hydrothermalen Behandlung auf Festigkeit und Phasenbestand von UHPC N2 - Ultrahochleistungsbeton (UHPC) zeichnet sich durch eine enorme hohe Druckfestigkeit von über 150MPa aus, während er gleichzeitig eine hohe Dichtheit besitzt. Im Schwerpunktprogramm SPP 1182 der DFG sind umfangreiche Untersuchungen zu verschiedensten Aspekten des UHPC durchgeführt worden, sodass die Voraussetzungen für eine breite Anwendung gegeben sind. T2 - 19. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 16.09.2015 PY - 2015 SN - 978-3-00-050225-5 VL - 1 SP - 12-02, 1-521 - 1-528 AN - OPUS4-34866 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voland, K. A1 - Weise, Frank A1 - Meng, Birgit T1 - Alkali-silica reaction in concrete pavements N2 - A significant number of German concrete motorway pavements have shown damage only a few years after construction. The alkali-silica-reaction (ASR) is often one of the reasons for this damage. German guidelines and regulations focus on the optimisation of the concrete composition to avoid damage due to ASR. Moreover, diverse research projects have dealt with the development and optimisation of ASR performance test methods with and without external alkali supply. However, the influence of other parameters on the occurrence and intensity of a damaging ASR had not yet been taken into account. Such parameters include, e.g., insufficient curing and the modifications of concrete’s porosity due to the use of slip form pavers. Likewise, the increased traffic loading had not yet been considered. The Federal Institute for Materials Research and Testing (BAM) assesses these parameters and processes in a number of projects. These projects aim primarily to increase the durability of the concrete pavements, in particular by improving preventive measures that may be taken before or after the construction of concrete pavements. This paper gives a short overview of BAM’s projects concerning ASR in concrete pavements. Furthermore, results regarding the influence of the cyclic traffic loading on ASR are presented. T2 - 8th International conference on concrete under severe conditions - environment and loading (ConSec) CY - Lecco, Italy DA - 13.09.2016 KW - Alkali-silica-reaction KW - ASR KW - Concrete pavements KW - Durability KW - Concrete's porosity KW - Cyclic traffic loading and mechanical pre-damage PY - 2016 DO - https://doi.org/10.4028/www.scientific.net/KEM.711.714 SN - 1662-9795 VL - 711 SP - 714 EP - 721 PB - Trans Tech Publications CY - Switzerland AN - OPUS4-39106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Huismann, Sven A1 - Korzen, Manfred A1 - Weise, Frank A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Betonabplatzungen unter Feuerangriff und der Einfluss von Polypropylenfasern auf die Mikrorissbildung T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 163 EP - 171 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-25185 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - MODINSYS - Entwicklung und Modifikation von Instandsetzungsmörteln für Beton- und Stahlbetonkonstruktionen T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 238 EP - 246 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-25178 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Entwicklung von modularen Instandsetzungsmörteln für den Einsatz an denkmalgeschützten Natursteinbauwerken T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 247 EP - 255 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-25177 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Rheologie von Instandsetzungsmörteln - aktuelle Untersuchungen mit dem Würpelgerät T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 58 EP - 66 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-25192 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herbst, Tristan A1 - Rübner, Katrin A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Ganzheitliche Bewertung der Einsatzmöglichkeiten von Sekundärrohstoffen in Beton T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Germany DA - 07.11.2011 PY - 2011 SN - 978-3-9814281-0-0 SP - 295 EP - 307 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25174 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Christian A1 - Fontana, Patrick A1 - Müller, Urs A1 - Meng, Birgit ED - Rogge, A. ED - Meng, B. T1 - Entwicklung von C-S-H-Phasen in autoklaviertem Ultra-Hochleistungs-Beton (UHPC) T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 PY - 2011 SN - 978-3-9814281-0-0 SP - 25 EP - 32 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25196 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilic, Ksenija A1 - Kühne, Hans-Carsten A1 - Meng, Birgit A1 - Roussel, N. ED - Rogge, A. ED - Meng, B. T1 - Modelling of fresh SCC flow through reinforced sections T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 PY - 2011 SN - 978-3-9814281-0-0 SP - 50 EP - 57 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Neue Erkenntnisse und Analysemethoden zum Phasenbestand und Gefüge des Zementsteins T2 - 52.DAfStb-Forschungskolloquium, BAM CY - Berlin, Germany DA - 2011-11-07 PY - 2011 AN - OPUS4-25226 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fontana, Patrick A1 - Meng, Birgit A1 - Hillemeier, B. T1 - Frühe autogene Verformungen von HPC - Beurteilung des plastischen Schwindens und spannungsinduzierender Verformungen durch Korrelation mit der Hydratationskinetik N2 - Der Einfluß der Mischungszusammensetzungen auf das frühe autogene Schwinden der Bindemittelmatrix von Hochleistungsbetonen wurde durch Korrelation mit der Hydratationskinetik untersucht. Durch die Analyse der Verformungsgeschwindigkeiten konnte eine Unterscheidung zwischen plastischen und spannungsinduzierenden Verformungen vorgenommen werden. T2 - 45. Forschungskolloquium des DAfStb CY - Wien, Österreich DA - 06.10.2005 KW - Hochleistungsbeton KW - Autogenes Schwinden KW - Hydratation KW - Porenstruktur PY - 2005 SN - 0005-9900 SN - 1437-1006 VL - 100 SP - 57 EP - 60 PB - Ernst CY - Berlin AN - OPUS4-11177 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühne, Hans-Carsten A1 - Maier, Bärbel A1 - Maultzsch, Matthias A1 - Meng, Birgit A1 - Meinhold, Uwe T1 - Verification of the suitability of shotcrete on low strength concrete surfaces T2 - 10th International Conference on Durability of Building Materials and Components (DBMC) CY - Lyon, France DA - 2005-04-17 KW - Hydraulic engineering structures KW - Low strength concrete KW - Repair systems KW - Performance tests PY - 2005 SP - 8 pages CY - Lyon AN - OPUS4-7413 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Urs A1 - Pliett, H. A1 - Wenzel, F. A1 - Meng, Birgit T1 - A sustainable approach for the conservation of the Timur Shah Mausoleum in Kabul, Afghanistan T2 - 10th International Conference on Durability of Building Materials and Components (DBMC) CY - Lyon, France DA - 2005-04-17 PY - 2005 SP - 1 EP - 8(?) CY - Lyon AN - OPUS4-7411 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Urs A1 - Fontana, Patrick A1 - Meng, Birgit T1 - BAM-Division VII.1 Building Materials: Main Expertise/NANOCEM Partner Project T2 - Nanocem Open meeting CY - Morges, Switzerland DA - 2005-04-29 PY - 2005 AN - OPUS4-7420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fontana, Patrick A1 - Meng, Birgit A1 - Habel, Wolfgang A1 - Wagenknecht, E. A1 - Hillemeier, B. T1 - Measurement of viscoelastic properties of cement pastes with oscillation rheometry T2 - 24th conference on Cement and Concrete Science CY - Warwick, England, UK DA - 2004-09-16 KW - Cement paste KW - Oscillation rheometry KW - Viscoelastic properties PY - 2004 SP - 1(?) EP - 4(?) AN - OPUS4-11178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Vermeidung stofflicher Probleme bei der Wärmebehandlung von Beton T2 - "Beton für alle Wetter" Fachseminar CY - Berlin, Germany DA - 2005-11-24 PY - 2005 AN - OPUS4-11473 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Aguiar, J. B. ED - Jalali, S. ED - Camoes, A. ED - Ferreira, R.M. T1 - MODINSYS modular systems for the protection and repair of concrete structures T2 - 13th International Congress on polymers in concrete - ICPIC 2010 CY - Funchal-Madeira, Portugal DA - 2010-02-11 KW - Betoninstandsetzung KW - Instandsetzungsmörtel KW - Modulare Systeme KW - SPCC KW - PCC KW - Repair mortar KW - Modular systems KW - Concrete rehabilitation PY - 2010 SN - 978-972-99179-4-3 SP - 697 EP - 704 CY - Funchal-Madeira, Portugal AN - OPUS4-20937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Müller, Urs A1 - Meng, Birgit A1 - Rübner, Katrin ED - Maierhofer, C. ED - Reinhardt, H.-W. ED - Dobmann, G. T1 - Analysis of solid components and their ratios in reinforced concrete structures KW - Concrete analysis KW - Concrete petrography KW - Optical microscopy KW - Scanning electron microscopy KW - Micro X-ray fluorescence analysis PY - 2010 SN - 978-1-84569-560-6 VL - 1 IS - Chapter 9 SP - 180 EP - 197 PB - Woodhead Publishing Ltd CY - Oxford AN - OPUS4-21050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -