TY - JOUR A1 - Jablonka, Kevin Maik A1 - Ai, Qianxiang A1 - Al-Feghali, Alexander A1 - Badhwar, Shruti A1 - Bocarsly, Joshua D. A1 - Bran, Andres M. A1 - Bringuier, Stefan A1 - Brinson, L. Catherine A1 - Choudhary, Kamal A1 - Circi, Defne A1 - Cox, Sam A1 - de Jong, Wibe A. A1 - Evans, Matthew L. A1 - Gastellu, Nicolas A1 - Genzling, Jerome A1 - Gil, María Victoria A1 - Gupta, Ankur K. A1 - Hong, Zhi A1 - Imran, Alishba A1 - Kruschwitz, Sabine A1 - Labarre, Anne A1 - Lála, Jakub A1 - Liu, Tao A1 - Ma, Steven A1 - Majumdar, Sauradeep A1 - Merz, Garrett W. A1 - Moitessier, Nicolas A1 - Moubarak, Elias A1 - Mouriño, Beatriz A1 - Pelkie, Brenden A1 - Pieler, Michael A1 - Ramos, Mayk Caldas A1 - Ranković, Bojana A1 - Rodriques, Samuel G. A1 - Sanders, Jacob N. A1 - Schwaller, Philippe A1 - Schwarting, Marcus A1 - Shi, Jiale A1 - Smit, Berend A1 - Smith, Ben E. A1 - Van Herck, Joren A1 - Völker, Christoph A1 - Ward, Logan A1 - Warren, Sean A1 - Weiser, Benjamin A1 - Zhang, Sylvester A1 - Zhang, Xiaoqi A1 - Zia, Ghezal Ahmad A1 - Scourtas, Aristana A1 - Schmidt, K. J. A1 - Foster, Ian A1 - White, Andrew D. A1 - Blaiszik, Ben T1 - 14 examples of how LLMs can transform materials science and chemistry: a reflection on a large language model hackathon N2 - Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines. KW - Large Language model KW - Hackathon KW - Concrete KW - Prediction KW - Inverse Design KW - Orchestration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589961 DO - https://doi.org/10.1039/d3dd00113j VL - 2 IS - 5 SP - 1233 EP - 1250 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, S. A1 - Samson, G. A1 - Masi, G. A1 - Achenbach, R. A1 - Bastidas, D. M. A1 - Bernal, S. A. A1 - Bignozzi, M. C. A1 - Criado, M. A1 - Cyr, M. A1 - Gartner, N. A1 - von Greve-Dierfeld, S. A1 - Legat, A. A1 - Nikoonasab, Ali A1 - Provis, J. L. A1 - Raupach, M. A1 - Gluth, Gregor T1 - Application of electrochemical methods for studying steel corrosion in alkali-activated materials N2 - Alkali-activated materials (AAMs) are binders that can complement and partially substitute the current use of conventional cement. However, the present knowledge about how AAMs protect steel reinforcement in concrete elements is incomplete, and uncertainties exist regarding the application of electrochemical methods to investigate this issue. The present review by EFC WP11-Task Force ‘Corrosion of steel in alkali-activated materials’ demonstrates that important differences exist between AAMs and Portland cement, and between different classes of AAMs, which are mainly caused by differing pore solution compositions, and which affect the outcomes of electrochemical measurements. The high sulfide concentrations in blast furnace slag-based AAMs lead to distinct anodic polarisation curves, unusually low open circuit potentials, and low polarisation resistances, which might be incorrectly interpreted as indicating active corrosion of steel reinforcement. No systematic study of the influence of the steel–concrete interface on the susceptibility of steel to corrosion in AAMs is available. Less common electrochemical methods present an opportunity for future progress in the field. KW - Alkali-activated materials KW - Reinforcement corrosion KW - Steel corrrosion KW - Electrochemical methods KW - Concrete PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572241 DO - https://doi.org/10.1002/maco.202313743 SN - 1521-4176 VL - 74 IS - 7 SP - 988 EP - 1008 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Munsch, Sarah A1 - Telong, Melissa A1 - Schmidt, Wolfram A1 - Bintz, Thilo A1 - Fladt, Matthias A1 - Stelzner, Ludwig T1 - The NMR core analyzing TOMograph: A multi-functional tool for non-destructive testing of building materials N2 - NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the material. Depending on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore structure. Moreover it enables the determination of moisture transport properties and the (re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and curing. However, as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale (< 10 mL) samples. This paper describes the capabilities of an NMR tomograph, which has been specifically optimized for the investigation of larger, heterogeneous building material samples (diameters of up to 72 mm, length of up to 700 mm) with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times (50 - 80 m s). KW - Fire spalling KW - Moisture transport KW - Concrete KW - Cement hydration KW - Sensitivity KW - Supplementary cementitous materials KW - Frost salt attack PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573755 DO - https://doi.org/10.1016/j.mrl.2023.03.004 SN - 2097-0048 VL - 3 IS - 3 SP - 207 EP - 219 PB - Elsevier B.V. AN - OPUS4-57375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Timofeev, Juri A1 - Azari, H. A1 - Satyanarayana, R. T1 - Controlled Creating of Delaminations in Concrete for Nondestructive Testing N2 - Locating and sizing delaminations is a common inspection task in the maintenance and quality control of construction and rehabilitation. Their detection is an important area of application of nondestructive testing in civil engineering (NDT-CE). To improve this application, NDT test systems and test solutions must be compared, for which specimens containing well-defined delaminations are needed to serve as a reference. Currently, there are no widely accepted procedures available for creating such flaws locally and reproducibly. This study presents procedures for creating artificial delaminations repeatably and as close as possible to natural delaminations. To produce the discontinuities only substances were used which can occur in concrete components and do not affect the application of NDT-CE methods. Ultrasonic pulse-echo (UPE) was used to test the flaws in the specimens. The delaminations were created by applying expansive mortar in prepared through holes. Three specimens with two delaminations each were built and tested using UPE. KW - Concrete KW - Reference KW - Delamination KW - Test specimen KW - Non-destructive testing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595201 DO - https://doi.org/10.1007/s10921-023-01044-7 SN - 0195-9298 VL - 43 IS - 1 SP - 1 EP - 13 PB - Springer Science and Business Media LLC AN - OPUS4-59520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tambara, R. F. A1 - Durlo Tambara, Luis Urbano A1 - Venquiaruto, S. D. A1 - Pereira da Costa, F. B. T1 - Evaluation of the mechanical performance and capillary absorption of concretes with incorporation of crystallizing admixtures and subjected to damage at early ages T1 - Avaliação do desempenho mecânico e absorção capilar de concretos com incorporação de aditivos cristalizante submetidos a danos nas primeiras idades N2 - This study assessed the self-healing phenomenon in the mechanical properties and capillary absorption of structural concretes. Two crystalline powder additives were evaluated, dosed according to the manufacturers’ recommendations. Crystalline additives increase the density of the C-S-H gel and form insoluble crystals, effectively blocking fissures. Three concrete mixes were produced: a reference mix, additive-X with 0.8%, and additive-Y with 2.0%, relative to the mass of cement. 75% of the rupture load was applied at 3- and 14-days to induce microfissures for comparison with the reference mix. Subsequently, self-healing was assessed at 28- and 76-days. The property of axial compressive strength was determined at 28-days, revealing that crystalline additives contributed to an average increase of 12% in this property. While the age of loading did not significantly impact axial compressive strength, there were significant variations among the types of additives studied, as indicated by ANOVA. Water absorption properties through capillarity were evaluated at 28- and 76-days, showing an average reduction of 42% in water absorption due to the use of crystalline additives. In conclusion, the inclusion of crystalline additives positively contributed to the self-healing of the studied concretes, suggesting a partial recovery of microfissures. N2 - Esta pesquisa avaliou o fenômeno de autocicatrização nas propriedades mecânicas e absorção capilar de concretos estruturais. Foram avaliados dois aditivos cristalizantes em pó, dosados de acordo com o teor recomendado pelos fabricantes. Aditivos cristalizantes aumentam a densidade do gel C-S-H e formam cristais insolúveis, bloqueando fissuras. Três traços de concreto foram produzidos: referência, aditivo-X com 0,8% e aditivo-Y com 2,0% em relação a massa do cimento. Aplicou-se 75% da carga de ruptura aos 3- e 14-dias para gerar microfissuras e comparar com a referência. Posteriormente, a autocicatrização foi avaliada aos 28- e 76-dias. A propriedade de resistência à compressão axial foi determinada aos 28-dias, revelando que os aditivos cristalizantes contribuíram para um aumento médio de 12% desta propriedade. A idade do carregamento dos concretos não apresentou um impacto significativo na resistência à compressão axial, mas apontou resultados significativos entre os tipos de aditivos estudados, conforme ANOVA. As propriedades de absorção de água por capilaridade foram avaliadas aos 28- e 76-dias, indicando uma redução de absorção de água média de 42% devido ao uso dos aditivos cristalizantes. Em conclusão, a incorporação dos aditivos cristalizantes contribuiu de maneira positiva para a autocicatrização dos concretos estudados, indicando uma recuperação parcial das microfissuras. KW - Self-healing KW - Crystalline admixture KW - Concrete KW - Cracks PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599140 DO - https://doi.org/10.1590/1517-7076-RMAT-2023-0355 SN - 1517-7076 VL - 29 IS - 1 SP - 1 EP - 20 CY - Rio de Janeiro AN - OPUS4-59914 LA - por AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klimek, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Zehfuß, Jochen T1 - Influence of thermal strain on concrete spalling N2 - Understanding the susceptibility to spalling of concrete members in case of fire is important to evaluate the residual load-bearing capacity. The investigations of the spalling phenomenon of a concrete mixture using real scale members are necessary but expensive to carry out. Reducing the specimen size leads to an increase of boundary effects that can result in a reduced spalling or absence of spalling. In this study, fire tests were carried out on unrestrained, single-sided exposed, cuboid shaped specimens (0.6 m x 0.6 m x 0.29 m) as well as unrestrained and steel ring restrained cylindrical specimens (Ø = 0.47 m, h = 0.29 m), which induce different boundary conditions. These fire tests were carried out on two ordinary concrete mixtures. The two mixtures differ only in the type of aggregates (quartz gravel and basalt grit) and were used to investigate the influence of the thermal expansion of the aggregate on the spalling behaviour of the concrete. The results show a significant increase of the spalling depth due to the restrained thermal expansion achieved by the applied steel rings. Additionally, the type of aggregate has a direct influence on the spalling behaviour of a concrete mixture. The reduction of the boundary effects by the steel rings recreate the test conditions in the centre of a large concrete member. Thus, this type of specimen is suitable to determine the susceptibility to spalling of a material (screening-tests) as preliminary investigations to full scale fire tests. KW - Spalling KW - Concrete KW - Fire test KW - Restraint KW - Screening test PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593350 DO - https://doi.org/10.1617/s11527-023-02274-x VL - 57 SP - 1 EP - 14 PB - Springer AN - OPUS4-59335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Keßler, S. A1 - Gluth, Gregor ED - Lothenbach, B. ED - Wieland, E. ED - Altmaier, M. T1 - Influence of salt aggregate on the degradation of hybrid alkaline cement (HAC) concretes in magnesium chloride-rich saline solution simulating evaporite rock N2 - Concretes produced from salt aggregate and hybrid alkaline cements, an alkali-activated slag/fly ash blend, or a Portland cement were exposed to a magnesium chloride-rich saline solution ([Mg2+] = 3.6 m, [Cl−] = 8.3 m), representing a solution formed after contact of surface water with evaporite rock (rock salt) in a nuclear waste repository. The hydration and deterioration of the concretes were studied with X-ray diffraction, thermogravimetric analysis, pH mapping and permeability measurements. The results show that calcium silicate hydrate (C-S-H) or sodium-substituted calcium aluminium silicate hydrate (C-N-A-S-H) and Friedel's salt were the major reaction products in the concretes prior to exposure to the saline solution. During exposure to the saline solution, increasing amounts of C-S-H/C-N-A-S-H dissolved, and gypsum and a secondary AFm phase formed. The durability of the concretes improved with increasing amounts of Portland clinker in the cements, due to the associated differences in permeability and chemical resistance. Nevertheless, a massive increase of permeability occurred for all concretes, likely caused by crack formation due to the formation of gypsum from anhydrite in the salt aggregate. Thus, the behavior of the concretes differed from, and was more complex than, the behavior of plain cement pastes. T2 - Joint 6th International Workshop on Mechanisms and Modelling of Waste/Cement Interactions (JCCW 2023) CY - Prague, Czech Republic DA - 20.11.2023 KW - Nuclear waste repository KW - Evaporite rock KW - Magnesium chloride brine KW - Concrete KW - Hybrid alkaline cement PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599928 DO - https://doi.org/10.1016/j.apgeochem.2024.106027 SN - 0883-2927 SN - 1872-9134 VL - 168 SP - 1 EP - 14 PB - Elsevier AN - OPUS4-59992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -