TY - JOUR A1 - Völker, Christoph A1 - Moreno Torres, Benjami A1 - Rug, Tehseen A1 - Firdous, Rafia A1 - Zia, Ghezal Ahmad Jan A1 - Lüders, Stefan A1 - Lisdero Scaffino, Horacio A1 - Höpler, Michael A1 - Böhmer, Felix A1 - Pfaff, Matthias A1 - Stephan, Dietmar A1 - Kruschwitz, Sabine T1 - Data driven design of alkali-activated concrete using sequential learning N2 - This paper presents a novel approach for developing sustainable building materials through Sequential Learning. Data sets with a total of 1367 formulations of different types of alkali-activated building materials, including fly ash and blast furnace slag-based concrete and their respective compressive strength and CO2-footprint, were compiled from the literature to develop and evaluate this approach. Utilizing this data, a comprehensive computational study was undertaken to evaluate the efficacy of the proposed material design methodologies, simulating laboratory conditions reflective of real-world scenarios. The results indicate a significant reduction in development time and lower research costs enabled through predictions with machine learning. This work challenges common practices in data-driven materials development for building materials. Our results show, training data required for data-driven design may be much less than commonly suggested. Further, it is more important to establish a practical design framework than to choose more accurate models. This approach can be immediately implemented into practical applications and can be translated into significant advances in sustainable building materials development. KW - Sustainable building materials KW - Sequential learning KW - Data-driven materials design KW - Alkali-activated building materials PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584376 UR - https://www.sciencedirect.com/science/article/pii/S095965262302379X DO - https://doi.org/10.1016/j.jclepro.2023.138221 SN - 0959-6526 SN - 1879-1786 VL - 418 SP - 1 EP - 13 PB - Elsevier CY - Amsterdam AN - OPUS4-58437 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Christoph A1 - John, Elisabeth A1 - Firdous, Rafia A1 - Hirsch, Tamino A1 - Kaczmarek, Daria A1 - Ziesack, Kevin A1 - Buchwald, Anja A1 - Stephan, Dietmar A1 - Kruschwitz, Sabine ED - Ferrara, Liberato ED - Muciaccia, Giovanni ED - di Summa, Davide T1 - Beyond Theory: Pioneering AI-Driven Materials Design in the Sustainable Building Material Lab N2 - This work focuses on Artificial Intelligence (AI)-driven materials design, addressing the challenge of improving the sustainability of building materials amid complex formulations. These formulations involve various components, such as binders, additives, and recycled aggregates, necessitating a balance between environmental impact and performance. Traditional experimental methods often fall short in managing the complexity of material composition, hindering fast enough development of optimal solutions. Our research explores complex composition materials design through a comprehensive, comparative lab study between Data-Driven Design, using SLAMD - an open-source AI materials design tool, and traditional Design of Experiments (DOE). We aimed to develop a high-performance, alkali-activated material using secondary precursors, aiming for a compressive strength exceeding 100 MPa after 7-days. The findings reveal that AI-driven design outperforms DOE in development speed and material quality, successfully identif. T2 - 4 RILEM Spring Convention and Conference on advanced construction materials and processes for a carbon neutral society 2024 CY - Milano, Italy DA - 07.04.2024 KW - Secondary Raw Materials KW - Data-Driven Design KW - Sequential Learning KW - Design of Experiments KW - Alkali-Activated Binder PY - 2024 SN - 978-3-03170281-5 DO - https://doi.org/10.1007/978-3-031-70281-5_31 SN - 2211-0852 VL - 2 SP - 274 EP - 282 PB - Springer AN - OPUS4-61662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwettmann-Lui, Kim A1 - Nytus, Nina A1 - Weigel, Sandra A1 - Radenberg, Martin A1 - Stephan, Dietmar T1 - Effect of multiple-repeated aging and rejuvenation processes on bitumen properties evaluated with physical and chemical tests and multivariate analysis methods N2 - This paper presents laboratory experiments on repeated bitumen aging and rejuvenation processes to assess multiple reuse feasibility. Three 50/70 penetration-graded bitumen samples were reused with four different rejuvenators without adding virgin binder. The experiments continued until significant material changes, such as inhomogeneities and increased stickiness, prevented reliable characterization. After each rejuvenation and aging process, physical and chemical properties were analyzed, resulting in a comprehensive dataset. Results indicate that the reuse of pure rejuvenators, without incorporating virgin binder, is limited. Cyclic reuse depends heavily on the rejuvenator and its interaction with the binder. Of the four rejuvenators tested, two bio-based products enabled the maximum reuse of four cycles. Therefore, the rejuvenators used in this project are more suitable as additives to improve the physical properties of the bitumen for reuse rather than as substitutes for the binder. The datasets were further evaluated using multivariate analysis methods to construct statistical models for two use cases: In the first use case, the samples are classified by their aging condition. In the second use case, the samples are differentiated according to the rejuvenators. The models were successfully validated, providing a promising framework for the classification of unknown bitumen samples for reuse. KW - Bitumen KW - Aging KW - Rejuvenation KW - Multiple recycling KW - DSR measurements KW - Reuse KW - FTIR spectroscopy KW - Multivariate analysis methods PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627563 DO - https://doi.org/10.1016/j.conbuildmat.2025.140734 SN - 1879-0526 VL - 472 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-62756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Pirskawetz, Stephan A1 - Meinel, Dietmar A1 - Babski, Veronika A1 - Kühne, Hans-Carsten T1 - Methoden zur Analyse des Bruchverhaltens hochfester Stahlfaserbetone N2 - Hochfeste und ultrahochfeste Stahlfaserbetone eignen sich aufgrund ihrer Eigenschaften für den Einsatz bei extremen mechanischen Beanspruchungen. Das für diesen Einsatz erforderliche duktile Bruchverhalten unter Zugbeanspruchung wird ausschließlich durch die Zugabe von geeigneten Stahlfasern und deren Wirkung in der Zementsteinmatrix erreicht. Für eine gezielte stoffliche Optimierung des Systems sind fundierte Kenntnisse zur Wirkungsweise der Stahlfasern notwendig, die bei bisherigen Untersuchungen lediglich auf Basis von klassischen Messverfahren zerstörender Prüfungen gewonnen wurden. Durch das Einbeziehen von Methoden der zerstörungsfreien Materialcharakterisierung können das Bruchverhalten hochfester und ultrahochfester Stahlfaserbetone orts- und zeitaufgelöst untersucht und die einzelnen Phasen des Schädigungsprozesses identifiziert werden. Anhand der vorliegenden Ergebnisse von Zugversuchen eines ultrahochfesten Stahlfaserbetons wird der kombinierte Einsatz von Methoden der zerstörungsfreien Materialprüfung gezeigt und deren Anwendbarkeit in der Analyse des Bruchverhaltens diskutiert. Das Hauptaugenmerk liegt dabei auf der Charakterisierung der ausschlaggebenden Versagensmodi unter Zugbelastung durch die einzelnen Verfahren und dem Vergleich zu klassischen Messmethoden (z. B. Extensometer). Die Zugversuche wurden dazu parallel durch optische Verformungsanalyse mittels Bildkorrelation (DIC), Schallemissionsanalyse (SEA) und 3-D-Computertomografie (CT) begleitet. KW - Stahlfaserbeton KW - Zugbeanspruchung KW - Optische Verformungsanalyse KW - Schallemission KW - Computertomografie PY - 2016 DO - https://doi.org/10.1002/bate.201600056 SN - 1437-0999 VL - 93 IS - 10 SP - 711 EP - 716 PB - Ernst & Sohn CY - Berlin AN - OPUS4-37767 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - Voland, Katja A1 - Pirskawetz, Stephan A1 - Meinel, Dietmar T1 - Analyse AKR-induzierter Schädigungsprozesse in Beton - Einsatz innovativer Prüftechniken T1 - Analysis of ASR-induced damage processes in concrete Application of innovative measurement techniques N2 - Zur Beurteilung der Alkaliempfindlichkeit der Gesteinskörnung finden normativ der Betonversuch mit Nebelkammerlagerung bei 40 °C und alternativ der 60 °C-Betonversuch Anwendung. Als Beurteilungskriterium für den Schädigungsprozess wird bei beiden Verfahren die an Betonprismen diskontinuierlich ermittelte Dehnung herangezogen. Auch bei den zusätzlich in der Nebelkammer gelagerten Würfeln beschränkt sich die Schadensanalyse auf eine diskontinuierliche Verfolgung der maximalen Breite der Oberflächenrisse. Im Rahmen des Beitrags wird eine neuartige, bereits erfolgreich erprobte zerstörungsfreie Prüfmethodik vorgestellt. Diese ermöglicht durch eine gleichzeitige kontinuierliche Dehnungs-, Schallemissions- und Ultraschallmessung eine kontinuierliche Verfolgung der inneren Gefügeveränderungen in den Betonprüfkörpern während der AKR-provozierenden Lagerung. Dabei wurden drei zeitlich aufeinanderfolgende Phasen der inneren Gefügeveränderung mit einer Dominanz von Hydratation, Rissbildung sowie vermutlicher Rissverfüllung mit Reaktionsprodukten identifiziert. Die ablaufenden Rissbildungsprozesse wurden zusätzlich mit diskontinuierlich durchgeführten röntgentomografischen Untersuchungen zeitlich und räumlich visualisiert. Die CT-Befunde wurden durch mikroskopische Untersuchungen bestätigt. N2 - The alkali-reactive potential of aggregates is assessed according to the German guidelines by two different test methods. These are the 40 °C fog chamber storage and as an alternative method the 60 °C concrete prism test. In both tests, the discontinuously measured expansion of ASR-generating stored concrete prisms is used as criterion for the internal Damage process. The damage analysis of the cubes additionally stored in the 40 °C fog chamber is also restricted to the discontinuous measurement of the crack width on the cubes surfaces. This paper describes an innovative, already successfully applied, non-destructive measurement methodology. This methodology enables a continuous monitoring of the internal damage processes in ASR-generating stored concrete specimens due to a continuous recording of expansion, acoustic emission and ultrasonic velocity. Thereby, three sequent phases of internal structural changes dominated by hydration, crack formation and filling of the cracks with ASR-gel and/or other reaction products can be detected. The crack formation wastemporally and spatially visualised by discontinuously applied X-ray computed tomography measurements. Microscopic analyses confirm the findings of the X-ray 3D-CT. KW - Beton KW - Frost- und Frost-Tausalz-Prüfung KW - CIF- und CDF-Prüfung KW - Röntgen-3D-CT KW - Photogrammetrie PY - 2012 DO - https://doi.org/10.1002/best.201200049 SN - 0005-9900 SN - 1437-1006 VL - 107 IS - 12 SP - 1 EP - 11 PB - Ernst CY - Berlin AN - OPUS4-27041 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Stephan, Dietmar A1 - Meng, Birgit A1 - Simon, Sebastian A1 - von Werder, Julia A1 - Hirsch, Tamino A1 - Manninger, Tanja T1 - Effect of gypsum on the hydration of fused cement clinker from basic oxygen furnace slag N2 - Fused cement clinker can be produced from molten basic oxygen furnace slag (BOFS) by way of a reductive thermochemical treatment. During the thermochemical treatment, oxidic iron is reduced to metallic iron and separated. The resulting low-iron slag has a chemical and mineralogical composition similar to ordinary Portland cement (OPC) clinker. In this study, the hydraulic reactivity of the fused clinker from BOFS with and without gypsum was investigated using isothermal calorimetry, differential scanning calorimetry, in situ X-ray diffraction and powder X-ray diffraction. Furthermore, a synthetic fused clinker without foreign ions and fused clinker produced by a mixture of both materials was studied. The hydraulic reaction of the fused clinker from BOFS was considerably slower than that of OPC. However, the reaction can be accelerated by adding gypsum as a sulfate carrier. Furthermore, the results showed an increased reaction rate with decreasing content of foreign ions such as Fe, P or Mn. KW - General Materials Science KW - Building and Construction PY - 2024 DO - https://doi.org/10.1680/jadcr.23.00070 SN - 0951-7197 SP - 1 EP - 19 PB - Telford AN - OPUS4-59391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -