TY - JOUR A1 - Schlick-Hasper, Eva A1 - Bethke, John A1 - Vogler, Nico A1 - Goedecke, Thomas T1 - Flow properties of powdery or granular filling substances of dangerous goods packagings - Comparison of the measurement of the angle of repose and the determination of the Hausner ratio N2 - To ensure safety when transporting dangerous goods, it is important to specify the flow properties of the respective solid filling substance of the packagings. For this purpose, the angle of repose is currently used for the UN approvals in Germany. Measurements were carried out on 12 powdery or granular substances applying the angle of repose measuring methods customary in the test centres. The results of the methods differ significantly from each other. In addition, some of the techniques cannot be applied for very cohesive or coarse-grained materials. The results for the angle of repose show a strong scatter for some constellations (coefficient of variation more than 20 %). Safety during transport of dangerous goods cannot be guaranteed with this currently practiced system of measuring the angle of repose. As a consequence, an alternative parameter to characterize the flow properties of bulk materials should be used in the recognized test centers for dangerous goods packagings, such as the Hausner ratio. This approach leads to more precise test results for the substances examined (maximum coefficient of variation 2.8 %). It also has advantages in terms of applicability and occupational safety. Since the flow properties are safety-relevant, both in terms of mechanical safety and safety against the release of dangerous substances, the testing practice in the recognized test labs should be improved and standardized. KW - Sift-proofness KW - Powders KW - Flowability KW - Flow properties KW - Angle of repose KW - Hausner ratio PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552990 DO - https://doi.org/10.1002/pts.2678 SP - 1 EP - 18 PB - Wiley online library AN - OPUS4-55299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Lehmann, Jens A1 - Bohlmann, Tatjana A1 - Kronemann, Jens T1 - Gel-bound Colourants as a Substitute for the Sprayed Application of pH-Indicator Solution N2 - In general, pH-sensitive colorants such as phenolphthalein are applied on freshly split surfaces of building structures to determine the state of carbonation. For years, it has been known that the aerosols of phenolphthalein are suspected of being carcinogenic. Hence, more work has currently being done on alternative indicators for the use in research and the use on construction sites. Over the past years, mainly pH indicators from other research areas and natural dyes were investigated for their usability to cementitious systems. This paper presents the experimental results of using phenolphthalein solution bound in agar-agar gel. This gel-bound indicator allows the future use of the already known phenolphthalein dye without the health hazards for the user. To demonstrate the flexibility of the gel-bound colorant, different application forms of the indicator were carried out and assessed. In addition, the results obtained by the different methods were statistically evaluated to ensure validity. The accuracy of the results was confirmed by thermogravimetric analysis and IR spectroscopic studies as reference methods. It has also succeeded to demonstrate the comparability of the results achieved by the gel-bound colorant with the results of the common sprayed application method. As an additional gain in knowledge, comparative results of indicator tests, TGA analysis, and FTIR investigation are shown. KW - Concrete Carbonation KW - Gel-bound Colorants KW - pH Indicator KW - Thermal Gravimetric Analysis KW - FTIR-ATR Measurements PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551493 UR - http://www.sciencepublishinggroup.com/j/ajce DO - https://doi.org/10.11648/j.ajce.20221003.16 SN - 2330-8729 SN - 2330-8737 VL - 10 IS - 3 SP - 135 EP - 144 PB - Science Publishing Group CY - New York, NY AN - OPUS4-55149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wieneke, K. A1 - Herbrand, M. A1 - Vogler, Nico A1 - Schwermann, R. A1 - Blankenbach, J. T1 - Messverfahren zur Bestimmung der Rautiefe von Betonoberflächen T1 - Measurement methods for determining the roughness of concrete surfaces N2 - Die zuverlässige Bestimmung der mechanischen Eigenschaften der Grenzfläche zwischen zwei Betonen unterschiedlichen Alters ist von großer Bedeutung für die Bemessung. Die Bewertung der Rauigkeit einer Betonoberfläche erfolgt über den Vergleichswert der mittleren Rautiefe. Als Standardverfahren für die Ermittlung der Rautiefe gilt das Sandflächenverfahren nach Kaufmann. Zur Verbesserung der Zuverlässigkeit bei der Ermittlung der Rautiefe von Betonoberflächen sowie zur Erweiterung der Anwendung auf vertikale und geneigte Oberflächen wurden alternative Messverfahren entwickelt, die auf optischen Messmethoden basieren. Solche Verfahren sind beispielsweise die Laser-Triangulation oder die Photogrammetrie. Im vorliegenden Beitrag wird die Anwendung der zuvor genannten Verfahren zur Ermittlung der Rauigkeit beschrieben. Im Rahmen von Untersuchungen an Deckenplatten mit Gitterträgern werden die Verfahren anschließend an aufgerauten Betonoberflächen vergleichend angewendet. N2 - A reliable determination of the mechanical properties of the interface between to concrete cast at different times of great importance for design of structural concrete. The assessment of the roughness of a concrete surface is realized by the reference value of the mean roughness. A standard method for determining the roughness is the so-called sand patch method by Kaufmann. To improve the reliability of roughness measurements of concrete surfaces and to extend the scope of use on vertical and inclined surfaces, alternative measurement methods have been developed which are based on optical methods. Such methods are for example the laser triangulation or photogrammetry. In this paper, the application of the aforementioned methods for determining the roughness is described. In the course of tests on semi-precast slabs, the methods are applied to roughened concrete surfaces for comparison. KW - Instandsetzung KW - Rautiefe KW - Laser PY - 2018 SN - 0005-6650 VL - 93 IS - September SP - 365 EP - 373 PB - Springer VDI CY - Düsseldorf AN - OPUS4-45870 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Drabetzki, Philipp A1 - Lindemann, Mathias A1 - Kühne, Hans-Carsten T1 - Description of the concrete carbonation process with adjusted depth resolved thermogravimetric analysis N2 - The thermal gravimetric analysis (TG) is a common method for the examination of the carbonation progress of cement-based materials. Unfortunately, the thermal properties of some components complicate the evaluation of TG results. Various hydrate phases, like ettringite (AFt), C-S-H and AFm decompose almost simultaneously in the temperature range up to 200 °C. Additionally, physical bound water is released in the same temperature range. In the temperature range between 450 °C and 600 °C the decomposition of calcium hydroxide and amorphous or weakly bound carbonates takes place simultaneously. Carbonates, like calcite, from limestone powder or other additives may be already contained in the noncarbonated sample material. For this research an attempt was made to minimise the influence of these effects. Therefore, differential curves from DTG-results of non-carbonated areas and areas with various states of carbonation of the same sample material were calculated and evaluated. Concretes based on three different types of cement were produced and stored under accelerated carbonation conditions (1 % CO2 in air). The required sample material was obtained by cutting slices from various depth of previously CO2-treated specimen and subsequent grinding. During the sample preparation, a special attention was paid that no additional carbonation processes took place. As reference method for the determination of the carbonation depth the sprayed application of phenolphthalein solution was carried out. Microscopic analysis where examined to confirm the assumptions made previously. Furthermore, the observed effect of encapsulation of calcium hydroxide by carbonates caused by the accelerated carbonation conditions was examined more closely. KW - Microscopy KW - Accelerated carbonation KW - Carbonation behaviour KW - Concrete KW - Thermal Analysis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530571 DO - https://doi.org/10.1007/s10973-021-10966-1 VL - 147 IS - 11 SP - 1 EP - 14 PB - Springer AN - OPUS4-53057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogler, Nico A1 - Barthel, Maria A1 - Leinitz, Sarah A1 - Kühne, Hans-Carsten ED - Ludwig, H.-M. T1 - Nachweis der Funktionalität von modifizierten Betonpflastersteinen N2 - In urbanen Zentren schreitet die Versiegelung von Oberflächen voran. Ursache ist die stetige Zunahme moderner Infrastruktur. Straßen und Plätze heizen sich stärker auf und begünstigen die Entstehung von Hitzeinseln (Urban Heat Island Effect). Dies wirkt sich zunehmend negativ auf die Lebensqualität innerhalb dieser Städte aus. Einen möglichen Lösungsansatz zur Abschwächung dieses Effekts bietet die Entwicklung von Betonpflastersteinen mit erweiterten Leistungsmerkmalen. Der Einsatz von wasserspeichernden Materialien kann zur Verringerung der Oberflächentemperatur durch Ausnutzung von Verdunstungskälte einen Beitrag leisten. Die speziellen Anforderungen an die Pflastersteine bedürfen genauerer Untersuchungen, wobei diese über den Umfang der Standardprüfungen hinausgehen und eine entsprechende Anpassung der Messtechnik zum Nachweis der Wirksamkeit erforderlich machen. Da die selbstkühlenden Pflastersteine nach dem Prinzip der Verdunstung arbeiten, ist sowohl die Fähigkeit der Speicherung als auch die Fähigkeit zur kontinuierlichen Abgabe von Wasser nachzuweisen. Der kühlende Effekt in Bezug auf Oberfläche und Umgebung steht dabei im Vordergrund. Des Weiteren sind Untersuchungen unter verschiedenen klimatischen Bedingungen sowohl unter Laborbedingungen als auch im Freifeldversuch durchzuführen. Die Prüfung der Druckfestigkeit und der kapillaren Wasseraufnahme und des sind ebenfalls Bestandteil der umfangreichen Untersuchungen. Durch den Einsatz von thermischer Messtechnik sowie mechanischer Prüfungen und Untersuchungen zur Dauerhaftigkeit ist es möglich eine Charakterisierung der Pflastersteine vorzunehmen und deren prinzipielle Funktionalität nachzuweisen. In diesem Beitrag werden die verschiedenen Möglichkeiten und die daraus resultierenden Ergebnisse vorgestellt und so Schlüsse zur Funktion und Anwendbarkeit von derartig modifizierten Betonpflastersteinen gezogen. T2 - 19. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 16.09.2015 KW - Modifizierte Betonpflastersteine KW - Dauerhaftigkeit KW - Temperaturverhalten PY - 2015 SN - 978-3-00-050225-5 VL - 24-01 SP - 1-1331 EP - 1-1338 AN - OPUS4-34871 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogler, Nico A1 - Barthel, Maria A1 - Kühne, Hans-Carsten T1 - Self-cooling concrete pavers – performance tests by long-term studies under various climatic conditions N2 - In the last several decades, the rural exodus has led to an increasing number of inhabitants in the urban areas. The increased building and infrastructural construction caused the transformation of the landscape and to an increased land sealing in these areas. Consequently, the increased land sealing influences the air temperatures in the cities, since houses, streets and squares heat up continuously. As a result, the city and metropolitan areas became significantly warmer than their surroundings - the effect is known as Urban Heat Island (UHI). These changes have a negative impact for the quality of life. To deal with the negative effects of UHI, a high level of technical and financial effort is necessary. The costs caused by the UHI effects are in the range of several billion US dollars worldwide per year. The recent studies on UHI showed that the established methods like parks and green spaces or bright coatings for roof areas will soon not be able to effectively cope with the UHI effect in urban areas. Therefore there is a need for additional methods to mitigate UHI effect in the cities. The streets, sidewalks and squares represent approximately 30% to 40% of the inner cities areas. If these areas are designed functionally, they can have a significant impact on the UHI. This contribution focuses on development of a concrete paving stone with self-cooling properties. For the cooling effect the evaporative cooling is used. The paving stone is able to store large quantities of water and deliver during appropriate environmental conditions. This paper deals with the results of the long-term experiments on the test-fields under different climatic conditions. To interpret the test-field-results, laboratory tests were carried out as well. The paper presents and discuss the obtained results, and points out the difficulties occurred. T2 - 2nd International conference on advances in cement and concrete technology in Africa CY - Dar es Salaam, Tanzania DA - 27.01.2016 KW - Urban heat island KW - Concrete paving stone KW - Self-cooling KW - Performance tests KW - Long-term studies KW - Hitzeinsel KW - Betonpflasterstein KW - Selbstkühlend KW - Nachweis der Wirksamkeit KW - Langzeitversuch PY - 2016 SP - 595 EP - 602 AN - OPUS4-35679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Lindemann, Mathias A1 - Drabetzki, Philipp A1 - Kühne, Hans-Carsten T1 - Alternative pH-indicators for determination of carbonation depth on cement-based concretes N2 - The most common method for determination of the carbonation depth is the sprayed application of indicator solutions, Phenolphthalein in particular. Since the aerosols of Phenolphthalein are suspected to be carcinogenic, efforts have been intensified to use alternative indicators for the determination of carbonation depth. The subject and aim of this research paper are to examine indicator solutions from Alizarin Yellow R, Thymol Blue and a Mixed Indicator. These indicator solutions are commercially available and are not suspected to be carcinogenic. For the purpose of this research, samples previously stored under accelerated carbonation conditions (1% CO2) were examined by thermogravimetric analysis (TGA) and examination of the pH value. Additionally, the electrolytic back-titration for determination of total CO2 amount was carried out comparatively to TGA. KW - Thermal analysis KW - Accelerated carbonation KW - pH-indicators KW - Concrete PY - 2020 DO - https://doi.org/10.1016/j.cemconcomp.2020.103565 VL - 109 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-50458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogler, Nico T1 - Nachweis der Funktionalität von modifizierten Betonpflastersteinen T2 - 19. Internationale Baustofftagung (ibausil) CY - Weimar DA - 2015-09-16 PY - 2015 AN - OPUS4-34656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Barthel, Maria A1 - Vogler, Nico A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten T1 - Outdoor performance tests of self-cooling concrete paving stones for the mitigation of urban heat island effect N2 - Rising temperatures worldwide pose an increasing challenge for safe and healthy living conditions. Particularly inner cities have been affected by these environmental changes because of the materials used to build houses, streets and infrastructure. The most common building material is concrete. It shows a specific heat capacity, while the heat conductivity for Standard concrete is low. Thus, the use of concrete generates a high capacity of heat storage. In addition, extensive soil sealing also contributes to the temperature rise of inner city areas compared to their surroundings. To mitigate this so-called urban heat island effect, a self-cooling concrete paver was developed. This paver is able to store water. The evaporation of the water at elevated temperatures provides a cooling effect. This paper focuses on determination of this new paver’s capability to cool the surface and the surrounding. The new paver’s cooling Qualities were analysed in a series of laboratory tests. To prove the results outside of laboratory conditions, two fields (12 m × 8 m) with self-cooling and reference pavers were installed in Spain. This paper presents and discusses the results of the tests. Correlation between reduced surface temperature of the self-cooling concrete pavers and the air temperature is examined. KW - Urban heat island KW - Concrete paving stone KW - Self-cooling KW - Performance tests KW - Hitzeinsel KW - Betonpflasterstein KW - Selbstkühlend KW - Nachweis der Wirksamkeit PY - 2017 DO - https://doi.org/10.1080/14680629.2016.1163282 SN - 1468-0629 SN - 2164-7402 VL - 18 IS - 2 SP - 453 EP - 463 AN - OPUS4-35741 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogler, Nico A1 - Gluth, Gregor A1 - Oppat, Klaus A1 - Kühne, Hans-Carsten ED - Uzoegbo, H.C. ED - Schmidt, Wolfram T1 - Optical measurement techniques to determine the properties of surfaces for the repair in the field of construction N2 - For several years, optical measuring techniques play an ever increasing role in various areas of construction. Applications ränge from simple laser-based distance measurements up to the use of advanced camera Systems to assess shape changes of components. The advantages of such Systems lie in the ränge of non-contact respectively in non-destructive measurement and in the high required accuracy and reproducibility. The continuous improvement and development of sensors and laser sources also opens constantly new applications and areas of applications. Already established measurement methods and technologies can be further developed and adapted to modern requirements. At BAM it is a laser-based measurement System has been developed that is capable to measure the roughness of component surfaces in equal to already established methods. T2 - ACCTA - International conference on advances in cement and concrete technology in Africa 2013 CY - Johannesburg, South Africa DA - 28.01.2013 KW - Surface KW - Roughness KW - Optical measurement systems PY - 2013 SN - 978-3-9815360-3-4 SP - 1063 EP - 1071 AN - OPUS4-27882 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Priebe, Nsesheye Susan A1 - Gluth, Gregor A1 - Vogler, Nico A1 - Simon, Sebastian A1 - Kühne, Hans-Carsten ED - Serdar, M. ED - Stirmer, N. ED - Provis, J. T1 - Investigation of calcined brick clays from Central Germany for use as a sustainable pozzolan N2 - The production of Portland cement causes a substantial environmental impact, since the calcination of limestone results in high emissions of carbon dioxide. The use of supplementary cementitious materials such as calcined clays as partial replacement for Portland cement offers a solution to limit this environmental impact. This paper investigates four clays from deposits in central Germany with the aim of obtaining pozzolans for the production of Portland-pozzolana cement. The results obtained show that the calcined clays possess pozzolanic properties, which differ depending on calcination temperature and the relative amounts of Kaolinite and 2:1 clay minerals. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Supplementary cementitious materials KW - Calcined clays KW - Blended cements KW - Brick clays KW - Illitic clays PY - 2019 SN - 978-2-35158-223-7 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. VL - 1 SP - 462 EP - 469 PB - RILEM Publications CY - Paris AN - OPUS4-47586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -