TY - JOUR A1 - Abbas, Z. A1 - Gabel, D. A1 - Krietsch, Arne A1 - Krause, U. T1 - Quasi-static dispersion of dusts for the determination of lower explosion limits of hybrid mixtures N2 - Knowledge of explosion limiting concentration of explosible materials is necessary forthe design of explosion protection measures. Currently employed methods of testing MEC of a dust cloud or LEL of a hybrid mixture are based on arbitrary assumptionsand possess technical limitations that often lead to values of MEC/LEL, which are unrealistically low or poorly reproducible. This contribution presents an improved method for experimental determination of MEC of a combustible dust cloud or LEL of a flammable gas or hybrid mixture. The new setup operates under laminar conditions and allows a uniform suspension of dust particles in an open top acrylic glass tube. Dust concentration is measured with the help of infrared sensors installed a few centimeters above and below the ignition source. In order to evaluate the dependence of MEC on flow front velocity, MEC of lycopodium was determined at four flow velocities. The results show that the flow field intensity does not significantly influence the MEC of lycopodium for the flow ranges tested in this work. Moreover, LEL of hybrid mixtures of lycopodium and methane was also tested at flow velocities of 4.7 cm/s, 5.8 cm/s, 7 cm/s and 11 cm/s and compared with the values obtained from other sources. The results suggest that the requirement of high energy pyrotechnical igniter may be relinquished, provided that a truly homogeneous suspension of dust particles could be achieved. Moreover, the effect of relative amount of dust and gas, on the course of ignition and flame propagation in hybrid mixtures at their LEL, was studied by the help of high speed videos. For hybrid mixtures of carbonaceous dusts (like lycopodium) at their LEL, ignition occurs in the gas phase, however, flame propagation is only possible through a two-way interaction of dust and gas during the course of combustion. KW - Dust explosions KW - Gas explosions KW - Lower explosion limit KW - Hybrid mixtures PY - 2022 DO - https://doi.org/10.1016/j.jlp.2021.104640 SN - 0950-4230 VL - 74 SP - 1 EP - 18 PB - Elsevier Ltd. AN - OPUS4-54077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Ma, C. A1 - Zhou, F. A1 - Hu, Y. A1 - Schartel, Bernhard T1 - A liquid phosphorous flame retardant combined with expandable graphite or melamine in flexible polyurethane foam N2 - A systematic series of flexible polyurethane foams (FPUF) with different concentrations of flame retardants, bis([dimethoxyphosphoryl]methyl) phenyl phosphate (BDMPP), and melamine (MA) or expandable graphite (EG) was prepared. The mechanical properties of the FPUFs were evaluated by a universal testing machine. The pyrolysis behaviors and the evolved gas analysis were done by thermogravimetric analysis (TGA) and TGA coupled with Fourier-transform infrared (TG-FTIR), respectively. The fire behaviors were studied by limiting oxygen index (LOI), UL 94 test for horizontal burning of cellular materials (UL 94 HBF), and cone calorimeter measurement. Scanning electronic microscopy (SEM) was used to examine the cellular structure's morphology and the postfire char residue of the FPUFs. LOI and UL 94 HBF tests of all the flame retarded samples show improved flame retardancy. BDMPP plays an essential role in the gas phase because it significantly reduces the effective heat of combustion (EHC). This study highlights the synergistic effect caused by the combination of BDMPP and EG. The measured char yield from TGA is greater than the sum of individual effects. No dripping phenomenon occurs during burning for FPUF-BDMPP-EGs, as demonstrated by the result of the UL 94 HBF test. EG performs excellently on smoke suppression during burning, as evident in the result of the cone calorimeter test. MA reduces the peak heat release rate (pHRR) significantly. The synergistic effect of the combination of BDMPP and EG as well as MA offers an approach to enhance flame retardancy and smoke suppression. KW - Bis([dimethoxyphosphoryl]methyl) phenyl phosphate KW - Expandable graphite KW - Flexible polyurethane foam KW - melamine KW - phosphorous flame retardant PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541840 DO - https://doi.org/10.1002/pat.5519 SN - 1099-1581 VL - 33 IS - 1 SP - 326 EP - 339 PB - Wiley AN - OPUS4-54184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marti, J. A1 - Schartel, Bernhard A1 - Oñate, E. T1 - Simulation of the burning and dripping cables in fire using the particle finite element method N2 - The behavior of the cable jacket in fire characterized by the tendency to melt and drip constitutes a major source of fire hazard. The reason is that the melted material may convey the flame from one point to another, expanding fire and contributing to the fire load. In this article, the capability of a new computational strategy based on the particle finite element method for simulating a bench-scale cables burning test is analyzed. The use bench-scale test has been previously used to simulate the full-scale test described in EN 50399. As the air effect is neglected, a simple combustion model is included. The samples selected are two cables consisting of a copper core and differently flame retarded thermoplastic polyurethane sheets. The key modeling parameters were determined from different literature sources as well as experimentally. During the experiment, the specimen was burned under the test set-up condition recording the process and measuring the temperature evolution by means of three thermocouples. Next, the test was reproduced numerically and compared with a real fire test. The numerical results show that the particle finite element method can accurately predict the evolution of the temperature and the melting of the jacket. KW - Dripping behavior KW - Particle finite element method KW - Cables in fire KW - Fire behavior KW - Fire simulation KW - Cable bundle PY - 2022 DO - https://doi.org/10.1177/07349041211039752 SN - 0734-9041 VL - 40 IS - 1 SP - 3 EP - 25 PB - Sage AN - OPUS4-54185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. T1 - Aerial Robot Olfaction - An Overview of Research @BAM N2 - This presentation gives an introduction to the gas-sensitive aerial robots developed at BAM, including various application examples in the field of mobile robot olfaction: gas source localization, gas distribution mapping, and trial following. T2 - The 6th Meeting of the Investigation Committee on Measurement of Odors and Applications of Their Psychological/Physiological Effects CY - Online meeting DA - 21.01.2022 KW - Mobile Robot Olfaction KW - Gas Tomography KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - Gas Source Localization KW - Gas Distribution Mapping KW - Trial Following PY - 2022 AN - OPUS4-54241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Berechnung der Einfügedämmung bei Schienenfahrwegen – die Impedanzmethode mit einem Freiheitsgrad N2 - Mit dieser Methode kann man die Einfügedämmung eines Schienenstützpunkts/einer Schwelle korrekt berechnen. Sie gilt in ihrer ursprünglichen Form für eine Unterschottermatte in einem Tunnel T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Online meeting DA - 20.1.2022 KW - Impedanzmethode KW - Elastische Elemente KW - Schienenfahrweg PY - 2022 AN - OPUS4-54243 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Schartel, Bernhard A1 - Lin, Xuebao A1 - Tan, Yi A1 - Schoch, R. A1 - Lang, M. A1 - Tröppner, O. A1 - Bosse, M. ED - Ziegahn, K.-F. T1 - Untersuchung der Witterungsbeständigkeit komplexer Funktionalitäten von Polymerwerkstoffen durch künstliche Bewitterung: Flammschutz N2 - In den letzten Jahrzehnten wurde die Degradation der polymeren Matrix von flammgeschützten Polymeren eingehend untersucht. Erst in den letzten Jahren jedoch hat sich die Frage der Lebensdauer der Funktionalität des Flammschutzes selbst als wichtige Fragestellung herauskristallisiert, z.B. bei Kabeln. Deshalb sollte diese Fragestellung durch systematisch-variierte künstliche Klima- und Bewitterungstests an flammgeschützten Polymerwerkstoffen untersucht werden. T2 - 50. Jahrestagung der Gesellschaft für Umweltsimulation (GUS) CY - Online meeting DA - 23.03.2022 KW - Flammschutz, Witterungsbeständigkeit, Langzeitbeständigkeit, UV, E&E PY - 2022 SN - 978-3-9818507-7-2 VL - 50 SP - 143 EP - 148 CY - Pfinztal (Berghausen) AN - OPUS4-54543 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kosareva, E. A1 - Gainutdinov, R. A1 - Michalchuk, Adam A1 - Ananyev, I. A1 - Muravyev, N. T1 - Mechanical Stimulation of Energetic Materials at the Nanoscale N2 - The initiation of energetic materials by mechanical stimuli is a critical stage of their functioning, but remains poorly understood. Using atomic force microscopy (AFM) we explore the microscopic initiation behavior of four prototypical energetic materials: 3,4-dinitropyrazole, 𝜖-CL-20, 𝛼-PETN and picric acid. Along with the various chemical structures, these energetic compounds cover a range of application types: a promising melt-cast explosive, the most powerful energetic compound in use, a widespread primary explosive, and a well-established nitroaromatic explosive from the early development of energetics. For the softest materials (picric acid and 3,4-dinitropyrazole), the surfaces were found to behave dynamically, quickly rearranging in response to mechanical deformation. The pit created by nanoscale friction stimulation on the surface of 3,4-dinitropyrazole doubled in volume upon aging for half an hour. Over the same time frame, a similar pit on picric acid surface increased in volume by more than seven-fold. Remarkably, increased humidity was found to reduce the rate of surface rearrangement, potentially offering an origin for the desensitization of energetic materials when wetted. Finally, we identify an inverse correlation between the surface dynamics and mechanical sensitivity of our test energetic compounds. This strongly suggests that surface dynamics influence a material’s ability to dissipate excess energy, acting as a buffer towards mechanical initiation. KW - Energetic materials KW - Mechanical Properties KW - Mechanical Sensitivity PY - 2022 DO - https://doi.org/10.1039/D2CP00832G VL - 24 IS - 15 SP - 8890 EP - 8900 PB - Royal Society of Chemistry AN - OPUS4-54562 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Hirschberger, Paul A1 - Bartholmai, Matthias ED - Holl, H. T1 - Flying ant robot for chemical trail detection and localization N2 - This paper presents first advances in the area of aerial chemical trail following. For that purpose, we equipped a palm-size aerial robot, based on the Crazyflie 2.0 quadrocopter, with a small lightweight metal oxide gas sensor for measuring evaporated ethanol from chemical trails. To detect and localize a 5 cm wide chemical trail, a detection criterion was developed that uses only relative changes in the transient phase of the sensor response. The reduction in signal strength dependence improves the robustness of its application. We tested our setup in first crossing-trail experiments showing that our flying ant robot can correlate an odor hit with the chemical trail within 0.14 m. Principally, this could enable aerial chemical trail following in the future. T2 - 37th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Linz, Austria DA - 21.09.2021 KW - Aerial robot KW - Trail following KW - Trail detection KW - Localization PY - 2022 DO - https://doi.org/10.1016/j.matpr.2022.02.594 SN - 2214-7853 VL - 62 SP - 2462 EP - 2465 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-54507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Update nach 10 Jahren Bewitterung - Langzeitkorrosionsverhalten nichtrostender Stähle in maritimer Atmosphäre N2 - Durch Fortführung der Untersuchungen aus einem Forschungsvorhaben wurden neun verschiedene Stahllegierungen unter maritimen Umgebungsbedingungen über zehn Jahre ausgelagert und deren Korrosionsverhalten untereinander verglichen und bewertet. Anhand der Ergebnisse der Auslagerungsprüfungen konnten Rückschlüsse auf die Einflüsse der Legierungszusammensetzung, der Oberfächenausführung und der Auslagerungszeit unter maritimen Auslagerungsbedingungen gewonnen werden. Die Proben der drei untersuchten Duplexwerkstoffe zeigten über den Auslagerungszeitraum von zehn Jahren sowohl mit als auch ohne Spaltgeometrie die beste Korrosionsbeständigkeit. Ebenso konnte der molybdänlegierte Ferrit 1.4521 eine vergleichbar gute Korrosonsbeständigkeit erzielen, wie die klassischen austenitischen Werkstoffe 1.4301 und 1.4404. T2 - Korrosionsschutz in der maritimen Technik 2022 CY - Online meeting DA - 27.01.2022 KW - Auslagerungsversuche KW - Korrosionsschutz KW - Korrosion KW - Nichtrostende Stähle PY - 2022 AN - OPUS4-54276 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rütters, H. A1 - Fischer, S. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Maßmann, J. A1 - Ostertag-Henning, C. A1 - Wolf, J. L. A1 - Pumpa, M. A1 - Lubenau, U. A1 - Knauer, S. A1 - Jaeger, P. A1 - Neumann, A. A1 - Svensson, K. A1 - Pöllmann, H. A1 - Lempp, C. A1 - Menezes, F. F. A1 - Hagemann, B. T1 - Towards defining reasonable minimum composition thresholds – Impacts of variable CO2 stream compositions on transport, injection and storage N2 - To set up recommendations on how to define “reasonable minimum composition thresholds” for CO2 streams to access CO2 pipeline networks, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the CCS chain. All investigations were based on a generic “CCS cluster scenario” in which CO2 streams captured from a spatial cluster of eleven emitters (seven fossil-fired power plants, two cement plants, one refinery and one steel mill) are collected in a regional pipeline network. The resulting CO2 stream (19.78 Mio t impure CO2 per year) is transported in a trunk line (onshore and offshore) and injected into five generic replicate storage structures (Buntsandstein saline aquifers) offshore. Experimental investigations and modeling of selected impacts revealed beneficial as well as adverse impacts of different impurities and their combinations. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the considered variable compositions and mass flow rates were observed. We recommend to define minimum composition thresholds for each specific CCS project through limiting i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of concentrations of critical impurities, and defining impurity combinations to be avoided. KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543004 DO - https://doi.org/10.1016/j.ijggc.2022.103589 SN - 1750-5836 VL - 114 SP - 1 EP - 14 PB - Elsevier CY - New York, NY AN - OPUS4-54300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hicke, Konstantin T1 - Monitoring von Strukturverhalten mittels integrierter verteilter faseroptischer Sensorik - Verteilte akustische Sensorik (DAS) N2 - Die verteilte faseroptische akustische Sensorik (DAS) wird vorgestellt, hinsichtlich ihrer Leistungsfähigkeit beschrieben und verschiedenste Anwendungsfelder, z.B. für das Zustandsmonitoring oder für seismische Messungen, beispielhaft gezeigt. Zudem werden mögliche Anwendungsfelder von DAS für den Kontext Kerntechnische Entsorgung (KTE) und Rückbau aufgezeigt. T2 - Online-Workshop „Dauerhafte Verschlussbauwerke für Endlager“ CY - Online meeting DA - 14.02.2022 KW - Verteilte faseroptische Sensorik KW - Verteilte akustische Sensorik KW - DAS KW - KTE KW - Monitoring Endlager PY - 2022 AN - OPUS4-54348 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Dejian A1 - Schmidt, Martin A1 - Huang, W. A1 - Wei, A. A1 - Krause, U. A1 - Wu, W. T1 - Inhibition effect of N2/CO2 blends on the minimum explosion concentration of agriculture and coal dusts N2 - Minimum explosion concentration (MEC) of three agriculture dusts and two coal dusts was studied via a 20-L explosion chamber to reveal the role of gaseous inhibitors. Both active method (CO2 diluting air) and passive method (CO2 replacing O2) were used. The TG and DTG thermal analysis tests were conducted to study the pyrolysis and combustion characteristics of dust samples. An alternative explosion criterion based on combustion duration time was used to determine MEC, and compared with the standardized overpressure method. Under 10-kJ ignition condition, as oxygen mole fraction (XO2) decreased from 21% to 10%, MEC of agriculture dusts and coal dusts respectively increased by around 5 times and 2 times. The active inerting method with a lower N2/CO2 ratio was found to have a better suppression effect on the explosion of the five carbonaceous dusts because the blend has a higher specific heat and a lower oxygen diffusion rate. KW - CO2/N2 ratio KW - Explosion criterion KW - Combustion kinetics KW - Inerting effect KW - Explosion characteristics PY - 2022 DO - https://doi.org/10.1016/j.powtec.2022.117195 SN - 0032-5910 VL - 399 SP - 1 EP - 12 PB - Elsevier B.V. AN - OPUS4-55013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ren, K. A1 - Guo, Y. A1 - Huang, W. A1 - Wei, A. A1 - Wu, Dejian T1 - Explosion characteristics of coal dusts in O2/N2 ambience: A novel method to determine limiting oxygen concentration N2 - The explosion characteristics of anthracite and bituminous coals in O2/N2 ambience were experimentally studied via a 20-L spherical explosion chamber with various ignition energies of 2, 5 and 10 kJ. A novel method based on combustion duration time was proposed for the first time, with an emphasis on the determination of the limiting oxygen concentration (LOC). The values of LOC determined by the alternative method were almost consistent with those obtained by using the standardized overpressure method, where the LOCs were above 21.6%, 19.8%, and 13.2% for anthracite coal and 11.4%, 9.6%, and 9.0% for bituminous coal when the ignition energy is 2, 5, and 10 kJ, respectively. But the newly proposed method was found to be much less affected by the ignition energy compared with the standardized overpressure method, taking combustion duration time as an explosion criterion thus had a higher efficiency and required fewer experiments. The results also showed that as oxygen concentration decreases from 21.6% to 14.4%, the maximum explosion pressure decreases from 0.4334 MPa to 0.1034 MPa for anthracite coal and from 0.5664 MPa to 0.3981 MPa for bituminous coal, respectively. Moreover, the effect of ignition energy varied with varying volatile matter content and ignition mechanism of coal dusts. The higher the volatile content, the less sensitive it is to the ignition energy. The newly proposed method will provide a reference for the new standard development, hazard analysis, explosion prevention and suppression by involving the use of inert gases of combustible powder industries. KW - Limiting oxygen concentration KW - Ignition energy KW - Coal dusts KW - Combustion duration time KW - Explosion criterion PY - 2022 DO - https://doi.org/10.1016/j.fuel.2022.124673 SN - 0016-2361 VL - 324, Part B SP - 1 EP - 11 PB - Elsevier Ltd. AN - OPUS4-55051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guo, Y. A1 - Ren, K. A1 - Wei, A. A1 - Tao, C. A1 - Huang, W. A1 - Zhao, Peng A1 - Wu, Dejian T1 - Iron dust explosion characteristics with small amount of nano-sized Fe2O3 and Fe3O4 particles N2 - Iron powder, as one of the most abundant metal fuels that can be used as recyclable carriers of clean energy, is a promising alternative to fossil fuels in a future low-carbon economy. It may pose a potential explosion hazard during the process of processing, storage, transport, and reduction/oxidation (redox). The explosion characteristics of iron dust in air were undertaken via a 20 L spherical explosion chamber with an emphasis on minimum explosion concentration (MEC) of iron dust. The alternative method of combustion duration time (tc) was used to determine MEC and compared with the standardized over pressure method. Two kinds of nano-sized iron oxides (Fe2O3 and Fe3O4) were used as inertants to determine the inhibition effect of different oxidation products. The iron dust explosion products with various shapes and sizes were found to be able to grow up 4–6 times of the iron dust for the first time. Adding small amount of Fe2O3 or Fe3O4 could reduce the explosion severity and sensitivity of iron dust. The MEC data determined by both methods were comparable. The addition of 5 % oxide has obvious inhibition effect under 1500 g/m3 concentration. With the increase of oxide concentration to 10 %, the inerting effect increases, and the MEC of iron dust increases more than 3 times. The increase of dust concentration will weaken the inerting effect. When the concentration increases from 500 g/m3 to 3000 g/m3, the weakening effect of 10 % Fe2O3 on the explosion pressure decreases from 38.45 % to 2.24 %, and 10 % Fe3O4 decreases from 46.21 % to 10.63 %. Unlike coal, biomass or aluminum dusts, the iron dust explosion was found to have a unique secondary acceleration of pressure rise rate for the first time. These results provide a fundamental basis to mitigate the iron dust explosion via solid inerting method without adding extra elements. KW - Iron dust KW - Iron oxides KW - MEC KW - Combustion duration time KW - Explosion products KW - Pressure rise rate PY - 2022 DO - https://doi.org/10.1016/j.fuel.2022.124786 SN - 0016-2361 VL - 324, Part C SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-55057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - The role of vehicle dynamics in train-induced ground vibrations and the detection of irregular axle-pulse responses due to a varying track support stiffness N2 - Train-induced ground vibrations are all generated by the vehicle, by static or dynamic vehicle loads. The most important and most accepted excitation are the dynamic wheel loads from the passage over track irregularities. Dynamic wheel loads will be compared from parallel axle-box and ground vibration measurements at more than seven sites. Some low-frequency excitation of ground vibrations, typically between 10 and 30 Hz, cannot be found in the axle-box measurements. Therefore, other vehicle modes, such as rigid bogie modes, flexible carriage modes, rigid and flexible wheelset modes, have been analysed for additional excitation forces. These vehicle dynamics analyses give an explanation for higher axle-box results at high frequencies, but not for the excitation of the higher low-frequency ground-vibration component. Finally, the effect of the moving static train loads will be analysed. For a regular track and soil, the moving static train loads yield the quasi-static response which exists only in the low-frequency nearfield of the track. If the support stiffness is randomly varying along the track, the pulses on the track generate an additional low-frequency component which is called the irregular pulse responses. This component will be demonstrated by numerical analysis where all axle pulses are superposed in frequency domain. KW - Wheelset KW - Vehicle-track interaction KW - Rail roughness KW - Random dynamics and vibrations KW - Modal analysis PY - 2022 DO - https://doi.org/10.1177/09544097221086064 SN - 0954-4097 VL - 236 IS - 10 SP - 1218 EP - 1233 PB - Sage CY - London AN - OPUS4-55000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Non-vegan flame-retardant (adjuvants in) biocomposites N2 - Emanating from developing flame retarded biocomposites, we have proposed renewable natural fibers (including keratin) taken from industrial waste as an authentic sustainable approach. More recently, we have investigated non-vegan flame retardant approaches. This paper loves to give you an insight into our ongoing projects on biogenic industrial wastes like leather, bone meal, and insects. Materials were characterized multi-methodically, flame retardant modes of action quantified, decomposition mechanism proposed, and synergisms explained. Considering the large quantities of leather waste (LW) in industrial-scale production, we underline LW as multifunctional bio-adjuvants. LW enhances the flame retardancy of poly(ethylene-vinyl acetate) (EVA) containing phosphorus flame retardants (P-FR). Products/by-products of the invertebrate and vertebrate farming, respectively, are promising bio-based adjuvants in flame retarded bio-epoxy thermosets. While the addition of bone meal yields the formation of an inorganic shield, protein-based powders from insects provide an intumescent behavior. In combination with a P-FR superior charring and self-extinguishing are obtained. Acknowledgement: In part of this work was supported by the Volkswagen Foundation grant “Experiment!” No. 97437. T2 - Fire and Polymers, workshop, ACS Division of Polymer Chemistry CY - Napa, California, US DA - 05.06.2022 KW - Fire behaviour KW - Renewable KW - Circular economy KW - Biocomposite PY - 2022 AN - OPUS4-55025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gleuwitz, F. Robert A1 - Battig, Alexander A1 - Schartel, Bernhard T1 - Tenebrio molitor Beetle as a “Nonvegan” Adjuvant to Flame Retardants in Tannic Acid-Based Epoxy Thermosets N2 - Material solutions that meet both circular bioeconomy policies and high technical requirements have become a matter of particular interest. In this work, a prospectively abundant proteinrich waste resource for the manufacturing of flame-retardant epoxy biocomposites, as well as for the synthesis of biobased flame retardants or adjuvants, is introduced. Different biomass fillers sourced from the cultivation of the mealworm beetle Tenebrio molitor are embedded in a bioepoxy resin cured with tannic acid and investigated regarding the fire performance of the thermosets. By means of spectroscopic and thermal analysis (attenuated total reflectance FTIR spectroscopy, thermogravimetric analysis-coupled FTIR spectroscopy, and differential scanning calorimetry), the influence of the biomass microparticles on the curing and thermal degradation behavior is evaluated. The final performance of the biocomposites is assessed based on fire testing methodology (limited oxygen index, UL-94, and cone calorimetry). Providing a high charring efficiency in the specific tannic acid-based epoxy matrix, the protein-rich adult beetle is further investigated in combination with commercial environmentally benign flame retardants in view of its potential as an adjuvant. The results highlight a char forming effect of nonvegan fillers in the presence of tannic acid, particularly during thermal decomposition, and point toward the potential of protein-based flame retardants from industrial insect rearing for future formulations. KW - Tannic acid KW - Flame retardancy KW - Sustainable KW - Epoxy resin KW - Insects PY - 2022 DO - https://doi.org/10.1021/acssuschemeng.2c00746 SN - 2168-0485 VL - 10 IS - 19 SP - 6313 EP - 6324 PB - ACS AN - OPUS4-54845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liebner, Christian T1 - BAM Testgelände Technische Sicherheit (TTS) N2 - Die Präsentation zeigt in Bild und Video die Möglichkeiten auf dem BAM TTS zur Durchführung von Versuchen unterschiedlicher Gefährlichkeitsstufen auf. Sie wendet sich an potentielle künftige Kooperationspartner aus dem Bereich der zivilen Sicherheitsforschung (Polizeibehörden, Feuerwehr, THW, andere Forschungseinrichtungen), um deren Forschungsbedarf mit den an der BAM vorhandenen Testmöglichkeiten abzugleichen und so ebenfalls dem Aufbau von überflüssigen konkurrierenden Parallelstrukturen an anderen Forschungseinrichtungen vorzubeugen. T2 - ForAn Anwendertreffen zum BMBF-Innovationsforum "Zivile Sicherheitsforschung" CY - Berlin, Germany DA - 02.05.2022 KW - Zivile Sicherheitsforschung KW - Großversuche KW - Testgelände PY - 2022 AN - OPUS4-54847 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 - CONF A1 - Hupp, Vitus T1 - Adhesive Tapes in Bonded Materials Fire Risk or Protective Layer? N2 - In the recent years, more and more products in construction and automotive industry are bonded by adhesive tapes instead of mechanical fasteners but there is no sufficient understanding of how these bonded, layered materials behave in fires. Our research project gives an insight of how adhesives and substrates interact with each other in different fire scenarios and how flame retardants function in pressure sensitive adhesive (PSA) tapes. A systematic investigation on the burning behavior of PSA tapes as free-standing films, as top layers on different substrates and as sandwich-like adhesive joints was performed. The burning behavior of free-standing PSA tapes and those used as a coating was significantly improved by using phosphorus-based flame retardants. Furthermore, it was shown that, depending on tape structure and substrate, the PSA tape can lower the fire risk by acting as an intermediate protection layer in bonded materials. T2 - Fire and Polymers CY - Napa, California, USA DA - 05.06.2022 KW - Pressure Sensitive Adhesives KW - Tapes KW - Fire Behavior KW - Bonded Materials PY - 2022 AN - OPUS4-55094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grunewald, Thomas T1 - Nichtelektrischer Explosionsschutz - Zündgefahren durch Funken - Grundlagen und Maßnahmen zum Explosionsschutz N2 - Hersteller von Geräten für den bestimmungsgemäßen Gebrauch in explosionsfähigen Bereichen müssen, wenn sie unter die Richtlinie 2014/34/EU fallen, für das Inverkehrbringen in EU-Mitgliedsstaaten eine Konformitätsbewertung durchführen. Dazu gehört eine Zündgefahrenbewertung, bei der auch nichtelektrische Zündquellen betrachtet werden müssen, zu denen die mechanischen Schlagvorgänge gehören. Bei dieser Zündquellenart kommt es infolge eines Schlages und/oder Reibens eines Bauteils auf ein anderes zu einer Energieumwandlung. Dadurch kommt es zu einer Temperaturerhöhung an der Kontaktstelle sowie unter Umständen zu einem Abtrennvorgang kleiner Partikel erhöhter Temperatur. Sowohl die heißen Reibflächen als auch die abgetrennten Partikel stellen potentielle Zündquellen explosionsfähiger Atmosphären dar. Edelstahl ist für Geräte für die Verwendung zum bestimmungsgemäßen Gebrauch im explosionsgefährdeten Bereich insbesondere in der Chemie ein wichtiger Konstruktionswerkstoff. Die Ergebnisse des Forschungsprojektes "Entwicklung normativer Anforderungen an explosionsgeschützte nichtelektrische Geräte resultierend aus der Zündfähigkeit mechanisch erzeugter Schlagfunken (NAMES)" zeigen, dass Schlagvorgänge mit Edelstählen eine erhebliche Zündgefahr von explosionsfähigen Brenngasgemischen darstellen können. Dabei bestehen jedoch mitunter deutliche Unterschiede zwischen den verschiedenen Brenngasgemischen. Besonders hohe Zündwahrscheinlichkeiten konnten bei Brenngasgemischen mit Brenngasen der IEC-Explosionsgruppe IIC beobachtet werden, die Acetylen bzw. Wasserstoff als Brenngas enthielten. Schläge im Wasserstoff/Luft-Gemisch waren dabei jedoch bedeutend zündwirksamer. In diesem Gasgemisch konnte bei niedrigen maximalen Schlagenergien bis 60 J sogar eine mitunter höhere relative Zündhäufigkeit beobachtet werden als bei Versuchen mit unlegiertem Baustahl. T2 - Ausbildung zum Explosionsschutzbeauftragten CY - Essen, Germany DA - 21.06.2022 KW - Mechanisch erzeugte Funken KW - Nichtelektrische Funken KW - Nichtelektrischer Explosionsschutz KW - Mechanischer Explosionsschutz KW - Schlagfunken KW - Schleiffunken KW - Reibfunken KW - Zündgefahrenbewertung KW - Funkenarme Werkzeuge KW - Funkenfreie Werkzeuge PY - 2022 AN - OPUS4-55098 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Dirk A1 - Ruwe, L. T1 - Experimental study on the performance of the standardized test method for detonation flame arresters N2 - Flame arresters are autonomous protection systems and are among the constructive explosion protection measures that limit the effects of an explosion. In this study, the performance of the standardized test method regulated in the DIN EN ISO 16852 standard for in-line flame arresters for stable and unstable detonations, which is mainly designed for atmospheric conditions, is examined. In an interlaboratory comparison, experiments are performed for different pressures before ignition and explosion groups according to the standardized test method. The experimental data is analyzed in detail to further optimize the test method and to thus achieve an improved reproducibility of detonation tests at high pressures, especially regarding the deflagration to detonation transition. Based on these results, an improved test method for detonation flame arresters will be developed, which will ensure better reproducibility as well as applicability under non-atmospheric conditions. T2 - 28th ICDERS 2022 CY - Naples, Italy DA - 19.06.2022 KW - Flame arrester KW - Explosion protection KW - Experimental tests PY - 2022 AN - OPUS4-55101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Elastische Elemente in der Emission, Transmission und Immission von Bahnerschütterungen N2 - Dieser Vortrag präsentiert einige Prinzipien und einige Beispiele zur Minderung von Eisenbahnerschütterungen. Die Prinzipien unterscheiden sich für die Minderungsmaßnahmen im Gleis, im Boden und bei Gebäuden. Kraftübertragungsfunktionen isolierter und nicht isolierter Gleissysteme, reflektierte und durchgelassene Wellenamplituden bei gefüllten Bodenschlitzen und die Übertragung der Freifeldschwingungen ins Gebäude werden analysiert. Bei den einfachen Gleismodellen muss der richtige Anteil der unabgefederte Fahrzeugmasse zum eindimensionalen Gleismodell hinzugefügt werden. Der Minderungseffekt eines gefüllten Bodenschlitzes ist von der Steifigkeit und nicht von der Impedanz des Schichtmaterials bestimmt. Bei einer elastischen Gebäudelagerung muss die Minderungswirkung mit der richtigen Boden- (Fundament-) Steifigkeit berechnet werden, und das abgeminderte Gebäudeverhalten hängt wesentlich von der effektiven Gebäudemasse ab, die mit zunehmender Frequenz deutlich kleiner als die starre Gebäudemasse ist. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Bludenz, Austria DA - 17.5.2022 KW - Erschütterungsminderung KW - Bahngleis KW - Bodenschlitz KW - Gebäudelagerung KW - Elastische Elemente PY - 2022 AN - OPUS4-54916 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liao, Chun-Man T1 - Passive and active bridge monitoring N2 - This research is to perform passive and active measurements on a large-scale prestressed concrete bridge model under the outdoor condition. Multi sensors were applied to this test structure – BLEIB, which is located at the BAM test site. The experimental evaluation of ultrasonic wave propagation and seismic noise recordings were considered for revealing the bridge damage condition, as a basic for developing a reliable bridge monitoring system. T2 - DGZfP-Jahrestagung 2022 CY - Kassel, Germany DA - 23.05.2022 KW - Bridge monitoring PY - 2022 AN - OPUS4-54918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Schartel, Bernhard T1 - It Takes Two to Tango: Synergistic Expandable Graphite–Phosphorus Flame Retardant Combinations in Polyurethane Foams N2 - Due to the high flammability and smoke toxicity of polyurethane foams (PUFs) during burning, distinct efficient combinations of flame retardants are demanded to improve the fire safety of PUFs in practical applications. This feature article focuses on one of the most impressive halogen-free combinations in PUFs: expandable graphite (EG) and phosphorus-based flame retardants (P-FRs). The synergistic effect of EG and P-FRs mainly superimposes the two modes of action, charring and maintaining a thermally insulating residue morphology, to bring effective flame retardancy to PUFs. Specific interactions between EG and P-FRs, including the agglutination of the fire residue consisting of expanded-graphite worms, yields an outstanding synergistic effect, making this approach the latest champion to fulfill the demanding requirements for flame-retarded PUFs. Current and future topics such as the increasing use of renewable feedstock are also discussed in this article. KW - Synergy KW - Phosphorus-containing flame retardant KW - Expandable graphite KW - Polyurethane foams PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551958 DO - https://doi.org/10.3390/polym14132562 SN - 2073-4360 VL - 14 IS - 13 SP - 2562 PB - MDPI AN - OPUS4-55195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liao, Chun-Man A1 - Fontoura Barroso, Daniel T1 - Investigation of temperature effects on ultrasonic velocity in a prestressed concrete bridge model N2 - Ultrasonic measurements have recently been applied in the context of structural health monitoring in civil engineering. The ultrasonic method is very sensitive to environmental conditions and material property changes, which might be caused by prestress losses and loading effects on the bridge. However, it remains a challenge to identify the damage mechanisms causing structural property changes from the above mentioned factors influencing ultrasonics. The focus of this contribution is to investigate the correlation between ultrasonic velocities and temperature by the coda wave interferometry (CWI) analysis. Long-term monitoring of a prestressed concrete bridge model under field conditions was carried out to observe the effect of temperature. The homogeneous change in concrete caused by temperature was revealed by applying the CWI method. The threshold value of the best correlation coefficients for the linear regression of temperature and ultrasonic velocity changes was also studied. Experimental assessment will provide a ratio for temperature correction to evaluate the pre-stressing force decrease and its consequences on crack opening or extension. T2 - Tagung EWSHM2022 CY - Palermo, Italy DA - 04.07.2022 KW - Ultrasonic Velocity KW - Coda Wave Interferometry KW - Temperature Correction KW - Prestressing Force KW - Bridge Monitoring PY - 2022 SN - 978-3-031-07257-4 SN - 978-3-031-07258-1 DO - https://doi.org/10.1007/978-3-031-07258-1_82 VL - 2 SP - 813 EP - 823 PB - Springer Nature AN - OPUS4-55289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liao, Chun-Man T1 - Investigation of temperature effects on ultrasonic velocity in a prestressed concrete bridge model N2 - Ultrasonic measurements have recently been applied in the context of structural health monitoring in civil engineering. The ultrasonic method is very sensitive to environmental conditions and material property changes, which might be caused by prestress losses and loading effects on the bridge. However, it remains a challenge to identify the damage mechanisms causing structural property changes from the above-mentioned factors influencing ultrasonics. The focus of this contribution is to investigate the correlation between ultrasonic velocities and temperature by the coda wave interferometry (CWI) analysis. Long-term monitoring of a prestressed concrete bridge model under field conditions was carried out to observe the effect of temperature. The homogeneous change in concrete caused by temperature was revealed by applying the CWI method. The threshold value of the best correlation coefficients for the linear regression of temperature and ultrasonic velocity changes was also studied. Experimental assessment will provide a ratio for temperature correction to evaluate the prestressing force decrease and its consequences on crack opening or extension. T2 - Tagung EWSHM2022 CY - Palermo, Italy DA - 04.07.2022 KW - Ultrasonic velocity KW - Coda wave interferometry KW - Temperature correction KW - Prestressing force KW - Bridge monitoring PY - 2022 AN - OPUS4-55290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wave propagation from hammer, vibrator and railway excitation – theoretical and measured attenuation in space and frequency domain N2 - The attenuation of wave amplitudes is ruled by the planar, cylindrical or spher-ical geometry of the wave front (the geometric or power-law attenuation) but also by the damping of the soil (an exponential attenuation). Several low- and high-frequency filter effects are derived for the layering and the damping of the soil, for the moving static and the distributed train loads and for a homoge-neous or randomly heterogeneous soil. Measurements of hammer- and train-induced vibrations at five sites have been analysed for these attenuation and filter effects. The measured attenuation with distance can be discribed by gen-eralised power laws and some reasons will be discussed. The theoretical filter effects can well be found in the measurements. T2 - 10th Wave Mechanics and Vibration Conference (WMVC)nce CY - Lisbon, Potugal DA - 04.07.2022 KW - Hammer impact KW - Train passage KW - Layered soil KW - Attenuation KW - Filter effects KW - Randomly heterogeneous soil KW - Scattering PY - 2022 AN - OPUS4-55246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hothan, Sascha T1 - Reaktive Brandschutzsysteme N2 - Die Präsentation gibt einen Überblick zum Anwendungsbereich und den -grenzen von reaktiven Brandschutzsystemen. Ferner werden Forschungsergebnisse der BAM vorgestellt. T2 - Stahlbau-Kalender-Tag 2022 CY - Stuttgart, Germany DA - 24.06.2022 KW - Reaktive Brandschutzsysteme KW - Feuerwiderstand KW - Stahlbau KW - Brandversuche KW - Dauerhaftigkeit PY - 2022 AN - OPUS4-55250 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Different types of continuous track irregularities as sources of train-induced ground vibration and the importance of the random variation of the track support N2 - Irregularities of the track are a main cause of train-induced ground vibration, and track maintenance is of great importance. Although geometric irregularities at the wheel-rail contact are widely used, other types of irregularities, such as stiffness irregularities, irregularities from different track positions and irregularities in the wave propagation, were analysed in the present study. The track behaviour was investigated by a multi-beam-on-soil model. This track model is coupled with a vehicle model to calculate the vehicle–track interaction. The track model was also used for the track filtering, which transfers a track support error to the equivalent rail irregularity or, conversely, the sharp axle pulse on the rail to a smoother pulse on the soil. In the case in which this filtering varies randomly along the track, the pulses of the moving static load induce a certain ground Vibration component (“the scatter of axle pulses”). This effect was calculated by the superposition of axle pulses in the frequency domain and by a stochastic simulation. Simultaneous vehicle, track and soil measurements at a certain site were used to evaluate the different excitation and ground Vibration components. The agreement between calculations and axle-box and soil measurements is good. The ground vibrations calculated from rail irregularities and corresponding dynamic loads, however, clearly underestimate the measured ground vibration amplitudes. Only the static load that is moving over a varying track support stiffness can produce the important mid-frequency ground Vibration component by the scatter of axle pulses. KW - Train-induced ground vibration KW - Geometric vehicle and track irregularities KW - Stiffness variation KW - Multi-beam track model KW - Track filtering KW - Dynamic axle loads KW - Static axle loads KW - layered soil PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543846 DO - https://doi.org/10.3390/app12031463 SN - 2076-3417 VL - 12 IS - 3 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54384 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Xin A1 - Krebber, Katerina T1 - Phase error analysis and unwrapping error suppression in phase-sensitive optical time domain reflectometry N2 - Phase-sensitive optical time domain reflectometry becomes an effective tool to realize distributed sensing, and the optical phase of the received light is usually used to quantify the strain for both dynamic and static measurement. The analysis on the overall phase error has been improved by considering the proportionality of the detection noise to the local optical power. The estimation accuracy is greatly improved by using the proposed theory, the probability density of the estimation accuracy over 99% is > 0.6, ∼39 times larger than the previously reported method. The phase unwrapping may malfunction due to the noisy signal, causing large phase errors. Point break detection algorithms are used to locate the incorrect phase unwrapping points, so the temporal evolution of the phase retrieved at each position can be divided into several sections with different offset. The phase unwrapping error is then suppressed by removing the offset. KW - Phase unwrapping KW - Distributed fiber sensing KW - Acoustic sensing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543919 DO - https://doi.org/10.1364/OE.446517 VL - 30 IS - 5 SP - 6934 EP - 6948 PB - Optica Publishing Group AN - OPUS4-54391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Morgan, A.B. T1 - Multicomponent Flame Retardants N2 - The important take home message of this chapter: When multicomponent flame retardant systems are applied to polymeric materials, it becomes possible to address multiple fire properties, increase efficiency, and minimize flame retardant use to maximize polymer property balance. Flame retardants are combined or used together with adjuvants or synergists; fibers and fillers make a crucial contribution to their fire properties. Multicomponent systems are discussed in their capacity as an overall powerful strategy for achieving and optimizing non-halogenated flame-retardant polymeric materials. KW - Flame retardants KW - Synergy KW - Adjuvants KW - Fillers KW - Fibres PY - 2022 SN - 978-1-119-75056-7 SP - 413 EP - 474 PB - Scrivener Publishing LLC CY - Bevery ET - 2nd Edition AN - OPUS4-54426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krankenhagen, Rainer A1 - Zirker, Stefan A1 - Joniertz, Florian T1 - Determination of thermal parameters of concrete by active thermographic measurements N2 - The knowledge of the thermal parameters of a particular concrete is essential for thermal design of a building, but also could help to identify and assess the state of a concrete structure. Active thermography has the potential to be applied onsite and to provide a fast investigation of thermal properties. In this work, three different concrete samples were investigated by active thermography in reflection and in transmission setup. It was found that this method yields the same results without direct contact as the Transient Plane Source (TPS) method as an established inspection tool. KW - Concrete KW - Effusivity KW - Thermal diffusivity KW - Photothermal KW - Thermography KW - Hot disc method KW - Parker method KW - Onsite inspection PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543781 DO - https://doi.org/10.1007/s10921-022-00861-6 SN - 0195-9298 SN - 1573-4862 VL - 41 IS - 1 SP - 1 EP - 20 PB - Springer AN - OPUS4-54378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fulawka, K. A1 - Kwietniak, A. A1 - Lay, Vera A1 - Jaskiewicz-Proc, I. T1 - Importance of seismic wave frequency in FEM-based dynamic stress and displacement calculations of the earth slope N2 - Reliable assessment of earthen dams’ stability and tailing storage facilities widely used in the mining industry is challenging, particularly under seismic load conditions. In this paper, we propose to take into account the effect of the dominant frequency of seismic load on the stability assessment of tailing/earthen dams. The calculations are performed by finite element modelling (FEM) with the Mohr–Coulomb failure criteria. To separate the frequency content from other dynamic parameters describing the seismic wave, synthetic waveforms with identical amplitude and attenuation characteristics, but differing spectral characteristics have been used. The analysis has been performed for three different slope angles and two scenarios of seismic wave propagation. Consequently, the changes of total displacement and shear stresses depending on the frequencies have been determined and clearly show that lower frequencies cause higher stress levels and displacement. Finally, the response surface methodology has been applied to determine how different parameters affect the slope stability under dynamic load conditions. Overall, this study is a first step to improve the existing methods to assess slope stability when considering seismic load. KW - Slope stability KW - Numerical analysis KW - Seismic load KW - Frequency analysis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-544047 DO - https://doi.org/10.2478/sgem-2022-0002 SN - 2083-831X VL - 44 IS - 1 SP - 82 EP - 96 PB - De Gruyter CY - Berlin AN - OPUS4-54404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Michalchuk, Adam A1 - Morrison, C. T1 - From lattice vibrations to molecular dissociation N2 - The ease with which an energetic material can be initiated by mechanical impact is a critical parameter directing material safety and application. While impact sensitivity metrics are traditionally derived experimentally, recent developments have highlighted that the phenomenon is amenable to first principles simulation. In this chapter, we will outline a fully ab initio approach to predict the relative impact sensitivities of energetic materials based on the mechanochemical principles that link the impact event to vibrational energy transfer. This mechanism is key to rationalizing how a mechanical impact—which deposits energy into the low-frequency lattice vibrations—results in a molecular response. By simulating the vibrational energy levels (the so-called phonon density of states, PDOS) using first-principles computational methods (typically dispersion-corrected plane-wave density functional theory, PW-DFT) we can calculate the relative rate of energy propagation from the delocalized low-energy lattice vibrations through to the localized molecular modes. The latter traps the energy, which eventually results in bond rupture through heightened vibrational excitation. This method, based on vibrational up-pumping, offers a route toward predicting the impact sensitivities of a broad range of energetic materials, provided the crystal structure of the compound (or salt or co-crystal) is known. While it does not offer insight into the sensitizing roles undoubtedly played by crystal defects or grain boundaries, it does provide a level of understanding at the molecular and crystal packing levels. Correspondingly, this approach offers a feedback mechanism to chemists and materials scientists to guide the design of new materials with desired impact sensitivity behavior. KW - Energetic materials KW - Density functional theory KW - Material design PY - 2022 DO - https://doi.org/10.1016/B978-0-12-822971-2.00010-3 VL - 22 SP - 215 EP - 232 PB - Elsevier B.V. AN - OPUS4-54717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - Charakterisierung von Salzbeton und alkali-aktivierten Material basierend auf der Schallemissionsanalyse N2 - Nach einer kurzen Einführung in die Schallemissionsprüfung und -Analyse wird ein Versuchsstand vorgestellt, der im Rahmen des Themenfeldprojektes Seal Waste Safe installiert wurde. Schwerpunkt des Vortrages sind die Schallemissionsmessungen an einem 150 l Demonstrator aus Salzbeton und einem weiteren aus alkali-aktiviertem Material. Neben der konventionellen Schallemissionsanaylse mit Aktivitäts- und Intensitätsparametern der Zeitsignale, werden auch frequenzbasierte Parameter zur Analyse andiskutiert. N2 - After a brief introduction to acoustic emission testing and analysis, an experimental test setup is presented, which was part of the Seal Waste Safe project (internal BAM project 2019-2022). Herein, the acoustic emission measurements of a 150 l demonstrator made of salt concrete and another one made of alkali-activated material are focused. In addition to the conventional acoustic emission analysis regarding the activity and intensity parameters of the detected time signals, also frequency-based parameters were discussed for analysis. T2 - Dauerhafte Verschlussbauwerke für Endlager CY - Online meeting DA - 14.2.2022 KW - Acoustic Emission KW - Schallemission KW - Salzbeton KW - Alkali aktiviertes Material KW - Geopolymer PY - 2022 AN - OPUS4-54937 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Königsbauer, Korbinian A1 - Wosniok, Aleksander A1 - Nöther, N. A1 - Schaller, B. T1 - Entwicklung eines praxistauglichen POF-basierten Messsystems mittels digitaler I-OFDR zur Dehnungsdetektion T1 - Development of a practicable POF-based measuring system using digital I-OFDR for strain detection N2 - Es wird ein faseroptisches Messsystem vorgestellt, welches auf Basis der Rayleigh-Rückstreumessung eine ortsauflösende Detektion von signifikant großen Dehnungen bei Bauvorhaben im von Anwendern geforderten Größenordnungsbereich von 3 % bis 10 % ermöglicht. Mit dem Verfahren der digitalen inkohärenten optischen Frequenzbereichsreflektometrie (I-OFDR) werden materialspezifische Vorteile robuster perfluorierter polymeroptischer Fasern (PF-POF) erschlossen. Für den angestrebten industriellen Einsatz für die Zustandsüberwachung im Bereich des Tunnel- und Spezialtiefbaus soll die spezifische Rückstreuzunahme in der PF-POF hochauflösend gemessen werden. Diese Veröffentlichung zeigt in ersten Projektergebnissen die Eignung des digitalen I-OFDR für eine Dehnungsdetektion von bis zu 10%. N2 - A fiber-optic measurement system is presented which, based on Rayleigh backscatter measurement, enables distributed detection of significantly large strains in construction projects in the range of 3 % to 10 % required by end users. The method of digital incoherent optical frequency domain reflectometry (I-OFDR) is used exploiting material-specific advantages of robust perfluorinated polymer optical fibers (PF-POF). For the intended industrial application for structural health monitoring in the field of tunnel construction and specialised civil and underground engineering, the specific backscatter increase in the PF-POF is to be measured with high resolution. This publication shows in first project results the suitability of the digital I-OFDR for strain detection up to 10%. T2 - 21. ITG/GMA-Fachtagung CY - Nuremberg, Germany DA - 10.05.2022 KW - Backscatter measurement KW - Optical fiber sensors KW - POF KW - I-OFDR KW - Strain measurement PY - 2022 SN - 978-3-8007-5835-7 SN - 0932-6022 VL - 303 SP - 139 EP - 143 PB - VDE VERLAG GMBH CY - Berlin · Offenbach AN - OPUS4-54851 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Winkler, Nicolas P. A1 - Schugardt, Jan ED - Rudnitskaya, A. T1 - Remote Drone-to-Drone Gas Sensing: A Feasibility Study N2 - Remote gas sensors mounted on mobile robots enable the mapping of gas distributions in large or poorly accessible areas. A challenging task however, is the generation of three-dimensional distribution maps from these spatially sparse gas measurements. To obtain high-quality reconstructions, the choice of optimal measuring poses is of great importance. Remote gas sensors, that are commonly used in Robot Assisted Gas Tomography (RAGT), require reflecting surfaces within the sensor’s range, limiting the possible sensing geometries, regardless of whether the robots are ground-based or airborne. By combining ground and aerial robots into a heterogeneous swarm whose agents are equipped with reflectors and remote gas sensors, remote inter-robot gas measurements become available, taking RAGT to the next dimension – releasing those constraints. In this paper, we demonstrate the feasibility of drone-to-drone measurements under realistic conditions and highlight the resulting opportunities. T2 - 19th International Symposium on Olfaction and Electronic Nose CY - Aveiro, Portugal DA - 29.05.2022 KW - Aerial robot KW - TDLAS KW - Inter-robot measurements KW - Gas tomography KW - Plume PY - 2022 SN - 978-1-6654-5860-3 DO - https://doi.org/10.1109/isoen54820.2022.9789627 SP - 1 EP - 3 PB - IEEE CY - USA AN - OPUS4-54926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. T1 - Remote Drone-to-Drone Gas Sensing: A Feasibility Study N2 - Remote gas sensors mounted on mobile robots enable the mapping of gas distributions in large or poorly accessible areas. A challenging task however, is the generation of three-dimensional distribution maps from these spatially sparse gas measurements. To obtain high-quality reconstructions, the choice of optimal measuring poses is of great importance. Remote gas sensors, that are commonly used in Robot Assisted Gas Tomography (RAGT), require reflecting surfaces within the sensor’s range, limiting the possible sensing geometries, regardless of whether the robots are ground-based or airborne. By combining ground and aerial robots into a heterogeneous swarm whose agents are equipped with reflectors and remote gas sensors, remote inter-robot gas measurements become available, taking RAGT to the next dimension – releasing those constraints. In this paper, we demonstrate the feasibility of drone-to-drone measurements under realistic conditions and highlight the resulting opportunities. T2 - 19th International Symposium on Olfaction and Electronic Nose CY - Aveiro, Portugal DA - 29.05.2022 KW - Aerial robot KW - TDLAS KW - Inter-robot measurements KW - Gas tomography KW - Plume PY - 2022 AN - OPUS4-54927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falkenhagen, Sandra F. T1 - black as hell, strong as death and sweet as love - pyrolyzed waste materials and cyclodextrins as effective filler in flame retarded epoxy composites N2 - Renewable alternatives for common thermoset resins are demanded to go for sustainability. The objective is to create a flame retarded epoxy resin from a commercial bio epoxy resin with halogen free inorganic and organic flame retardants, respectively. Alumina trihydrate, aluminum diethyl phosphinate, a DOPO-based phosphonamidate and ammonium polyphosphate seem to have promising performances. Properties are enhanced with different bio fillers: pyrolyzed cocoa shells and plant waste (provided by Otto A. Müller Recycling GmbH, thanks!), short fibers and nonwovens of the natural fiber kenaf, hydroxypropyl-ß-cyclodextrin and sulfobutylether-ß-cyclodextrin. Fire performance is investigated by cone calorimeter examinations, LOI and UL-94 ratings. Thermal analysis is given by TG-FTIR and DSC measurements. Combinations of flame retardants and bio-fillers lead to reduced PHRR and THR, reach V0 in UL-94 and have a significant increase in LOI of up to 37 vol.-%. 10 % ammonium polyphosphate with 10 % pyrolyzed cocoa shell performs best, builds a magnificent protective layer, and shows good intumescence. T2 - 3rd international conference on eco-friendly flame retardant additives and materials CY - Alès, France DA - 17.05.2022 KW - Epoxy resin KW - Flame retardant KW - Kenaf fiber KW - Pyrolyzed plant waste KW - Cyclodextrin PY - 2022 AN - OPUS4-54928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Performance of intumescent fire protection coatings applied to structural steel tension members with circular solid and hollow sections N2 - Intumescent fire protection coatings are used to improve the fire resistance of steel members. Due to slender cross-sections typically used for tension members, high demands are placed on the effectiveness and reliability of the intumescent coatings. This paper describes real-scale fire tests of intumescent coatings applied to steel tension members with circular solid and hollow sections. First, the current regulations for the application of intumescent coatings on steel tension members are discussed. After that, a comparison between the foaming behaviour and failure mechanisms of intumescent coatings applied to steel tension members with different cross-sections and loading conditions is given. Next, the experimental setup and procedure of the performed fire tests are presented. In addition, the influences of various parameters on the performance of the intumescent coating are analysed, including the geometry of the steel profile, dry film thickness of the intumescent coating, load utilisation level as well as the orientation of the member. Based on the theoretical considerations and results of the fire tests, it is evidenced that mechanically loaded fire tests are essential to assess accurately the contribution of intumescent fire protection coatings to the fire resistance of steel tension members with circular solid sections. KW - Fire tests KW - Intumescent coating KW - Reactive fire protection system KW - Steel KW - Tension members PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548981 DO - https://doi.org/10.1016/j.firesaf.2022.103605 SN - 0379-7112 VL - 131 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-54898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hicke, Konstantin T1 - Distributed fiber optic sensing @BAM N2 - Research and developement activities of BAM regarding Distributed Fiber Optic Sensing are portrayed using exemplary previous and current projects. Shown results pertain to distributed acoustic sensing (DAS), distributed temperagture sensing (DTS) and distributed strain sensing (DSS). T2 - Seismic seminar FU Berlin (group Prof. Shapiro) CY - Online meeting DA - 15.09.2022 KW - Distributed fiber optic sensing KW - Distributed acoustic sensing KW - Distributed temperature sensing KW - Distributed strain sensing KW - Infrastructure monitoring PY - 2022 AN - OPUS4-55721 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - European test standard for intumescent coatings applied to steel tension bars with solid section N2 - Description of the FIRESTEMIC project and the newly developed test standard for reactive fire protection systems on steel tension members. T2 - Symposium 2022 Heißbemessung - Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Fire tests KW - Tension member KW - Intumescent coating KW - Steel KW - Test standard PY - 2022 AN - OPUS4-55702 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Peter, A. A1 - Rohleder, R. A1 - Hothan, Sascha T1 - European test standard intumescent coatings applied to steel tension bars with solid section N2 - Intumescent coatings are used in civil engineering to improve the fire resistance of steel constructions. Due to the thin coating thickness and the profile-following application, the architectural appearance of the steel structure can be preserved. EN 13381-8 provides regulations to determine the contribution to the fire resistance of intumescent coatings applied to steel beams and columns. The scope of this standard excludes tension members and steel members with solid sections. For products that have already been successfully tested and assessed on beams and columns, EN 13381-10 offers the possibility based on unloaded fire tests to extend the scope of application of intumescent coatings to tension bars with solid sections. This approach contradicts the national safety level in Germany, where mechanically loaded testing is mandatory. Therefore, a new part of the test standard series EN 13381 is currently developed to enable the application of intumescent coatings on steel tension bars with solid section based on mechanically loaded fire tests. BAM has already carried out numerous fire tests on loaded steel tension members with intumescent coatings. Currently, in the BAM research project FIRESTEMIC, the influence of the steel bar orientation and the profile type on the thermal performance of intumescent coatings are investigated. Both questions concerning the thermal protection ability of intumescent coatings were analysed based on three different test sets, which were carried out in the tension furnace (Fig. 1a). The fire exposure corresponds to the standard temperature-time curve according to EN 1363-1. This paper summarises the main findings from the fire tests conducted in the FIRESTEMIC project. The results serve as an experimental background for the proposal of the new standard. Regarding the bar orientation, a new test setup was developed and proposed for the new standard. The two tested commercial water-based intumescent coatings with applied dry film thickness from 1.5 mm to 2.5 mm showed only a slight dependence on the bar orientation. In terms of the steel profile type, circular and rectangular solid sections with identical section factor and applied dry film thickness were tested. It was observed that the circular solid bars with diameter 30 mm heat up faster compared to the solid rectangular bars with dimension 30×30 mm (Fig. 1b). Also at larger steel bars, i.e. diameter 40 mm and dimension 40×40 mm, the same trend occurred. Thus, it is recommended for the new test standard to allow a transfer of the test results from circular to rectangular solid sections. In addition, the paper will describe and explain the test and assessment procedure proposed for the newly developed standard. T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Fire test KW - Steel KW - Tension member KW - Intumescent coating KW - Test standard PY - 2022 SP - 1 EP - 14 PB - TU Braunschweig CY - Braunschweig AN - OPUS4-55703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Brandversuch eines Stahlzuggliedes mit reaktivem Brandschutzsystem N2 - Das Poster stellt den im Rahmen des Workshops "Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung" durchgeführten Brandversuch vor. T2 - Workshop - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Brandschutz KW - Brandversuch KW - Feuerwiderstand KW - Reaktives Brandschutzsystem PY - 2022 AN - OPUS4-55699 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - Research Project FIRESTEMIC - Results and Recommendations N2 - The presentation summarizes the results of the research project. T2 - Workshop 2022 - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Fire tests KW - Intumescent coating KW - Steel KW - Tension member PY - 2022 AN - OPUS4-55700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Neue Prüfnorm für reaktive Brandschutzsysteme auf Stahlzuggliedern N2 - Der Vortrag stellt den Entwurf der neuentwickelten Prüfnorm vor. T2 - Workshop 2022 - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Feuerwiderstand KW - Brandschutz KW - Stahlzugglieder KW - Reaktives Brandschutzsystem KW - Prüfnorm PY - 2022 AN - OPUS4-55701 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Patzelt, Anne-Katrin A1 - Krentel, Daniel A1 - Wiesner, Anja T1 - InnoBOSK - Ergebnisse der Bedarfserhebung N2 - Im Projekt InnoBOSK wurden insgesamt vier wissenschaftlich basierte Bedarfserhebungsworkshops durchgeführt. Die Workshops hatten jeweils thematische Schwerpunkte und wurden mit Vertretern unterschiedlicher BOS (Behörden und Organisationen mit Sicherheitsaufgaben) durchgeführt. In der vorliegenden Arbeit werden die erhobenen Bedarfe ausgewertet. KW - BOS KW - InnoBOSK KW - Bedarfserhebung KW - Forschungsbedarf PY - 2022 SP - 1 EP - 23 AN - OPUS4-55831 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Überwachung von Brücken mit digitalen Methoden N2 - Brücken werden durch Inspektionen und teilweise durch Monitoring überwacht, um Daten und Informationen über den Zustand und die Einwirkungen zu sammeln. Auf deren Grundlage werden Entscheidungen hinsichtlich Maßnahmen zur Gewährleistung der Sicherheit und Verfügbarkeit getroffen. In diesem Vortrag werden die Potentiale der Digitalisierung zur Unterstützung und Verbesserung der Brückenüberwachung diskutiert. Insbesondere werden die Bereiche Datenmanagement, Brückenmodellierung und Entscheidungsfindung betrachtet. T2 - BVPI Arbeitstagung 2022 CY - Berlin, Germany DA - 16.09.2022 KW - Entscheidungsfindung KW - Brücken KW - Überwachung KW - Digitalisierung KW - Datenmanagement KW - Modellierung PY - 2022 AN - OPUS4-55770 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grunert, Wiebke A1 - Walter, Astrid A1 - Schwarz, Silke T1 - Forschung zur zivilen Sicherheit: Homemade Explosives besser erkennen und Anschläge verhindern N2 - Terroranschläge stellen nach wie vor eine stete Bedrohung für Gesellschaften weltweit dar. Häufig bedienen sich Terroristen*innen dabei selbsthergestellter Explosivstoffe, auch als homemade explosives (HMEs) bezeichnet, die aus alltäglichen Chemikalien in improvisierten Laboratorien hergestellt werden. Anleitungen für die Herstellung solcher Explosivstoffe werden im Internet geteilt und setzen meist kein oder nur ein rudimentäres Verständnis der Chemie voraus. Um geplante Terroranschläge schon während der Phase der Herstellung zu vereiteln, werden Methoden entwickelt, die frühzeitig Hinweise auf solche Aktivitäten geben. In dem EU-geförderten Projekt ODYSSEUS wird in enger Zusammenarbeit zwischen Behörden und Organisationen mit Sicherheitsaufgaben (BOS) sowie Partnern aus Industrie und Forschung an der Entwicklung neuer Methoden zur Erkennung von HMEs und ihrer Ausgangsstoffe gearbeitet. KW - Terroranschläge KW - EU Projekt ODYSSEUS KW - HMEs PY - 2022 DO - https://doi.org/10.37307/j.2199-7349.2022.09 SN - 2199-7349 VL - 2022 IS - 09 SP - 391 EP - 361 PB - Erich Schmidt Verlag CY - Berlin AN - OPUS4-55747 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -