TY - JOUR A1 - Schwettmann, K. A1 - Nytus, N. A1 - Weigel, Sandra A1 - Radenberg, M. A1 - Stephan, D. T1 - Effects of rejuvenators on bitumen ageing during simulated cyclic reuse: A review N2 - Single reuse of asphalt is an approved practice, but its success highly depends on restoring the properties of the aged binder. Rejuvenators have become increasingly important for softening the binder because they make it possible to increase the amount of reclaimed asphalt pavement (RAP) while reducing the dependence on virgin bitumen. The vital questions to be investigated are how the rejuvenators affect the ageing properties of bitumen and if rejuvenators offer the possibility of cyclic bitumen reuse. The main objective of this publication is to present the current state of the art regarding the effects of rejuvenators on bitumen ageing. The results of laboratory life cycle simulations indicate that repetitive ageing and rejuvenation processes are possible, but reuse mainly depends on the rejuvenator type and its interaction with the respective bitumen sample. There are rejuvenators that have good rejuvenating properties but accelerate subsequent ageing, which is essential to consider when evaluating a rejuvenator. Bitumen rejuvenated with petroleum-based products, such as aromatic extracts, performs slightly better after subsequent ageing than when rejuvenated with bio-based products. As there are a limited number of studies simulating cyclic bitumen reuse, more studies are necessary to evaluate the general limits of bitumen reuse. KW - Bitumen KW - Asphalt KW - Ageing KW - Rejuvenator KW - Recycling KW - Cyclic reuse KW - Multiple reuse PY - 2023 DO - https://doi.org/10.1016/j.resconrec.2022.106776 SN - 0921-3449 VL - 190 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-56963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Sielaff, S. A1 - Kunsic-Nowak, T. A1 - Nytus, N. A1 - Schwettmann, K. A1 - Schulze, C. A1 - Wetekam, J. T1 - Die FTIR-Untersuchung von Bitumen: Chancen, Durchführung und Präzision N2 - Die Fourier-Transformations-Infrarot-Spektroskopie (FTIR-Spektroskopie) stellt eine innovative und wirkungsvolle Methode zur Charakterisierung von Bitumen und bitumenhaltigen Bindemitteln dar. So erlaubt die FTIRCharakterisierung nicht nur eine Bewertung des Alterungsfortschritts eines Bindemittels, sondern zudem auch die Identifizierung von im Bitumen enthaltenen Additiven und Schadstoffen wie z. B. polyzyklischen aromatischen Kohlenwasserstoffen (PAK), die Ableitung verschiedener physikalischer und chemischer Kennwerte sowie weiterhin eine Klassifizierung von Bindemitteln nach verschiedenen übergeordneten Eigenschaften wie der Raffinerie, dem Alterungszustand und auch der Alterungsempfindlichkeit. KW - Bitumen und bitumenhaltige Bindemittel KW - FTIR-Spektroskopie KW - Anwendungsmöglichkeiten KW - Vergleichuntersuchung KW - Arbeitsanleitung KW - Präzision PY - 2023 UR - https://www.kirschbaum.de/fachzeitschriften/strasse-und-autobahn/strasse-und-autobahn/aktuelles-heft-17.html DO - https://doi.org/10.53184/STA8-2023-4 VL - 74/8 SP - 630 EP - 642 PB - KIRSCHBAUM VERLAG GmbH CY - Bonn AN - OPUS4-59049 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. A1 - Stephan, D. A1 - Nytus, N. A1 - Radenberg, M. A1 - Weigel, Sandra T1 - Post carbon road - The endless cycle of bitumen reuse N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Comgress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 SP - 1 EP - 14 AN - OPUS4-53490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. A1 - Stephan, D. A1 - Nytus, N. A1 - Radenberg, M. A1 - Weigel, Sandra T1 - Post carbon road - The endless cycle of bitumen reuse N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Congress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 AN - OPUS4-53489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -