TY - CONF A1 - Priebe, Nsesheye Susan A1 - Schmidt, W. T1 - Spearhead network for innovative, clean and safe cement and concrete technologies (SPIN) project in east, central and southern Africa T2 - 2nd Environmental cement Africa conference CY - Nairobi, Kenya DA - 2011-05-11 KW - SPIN KW - Africa KW - Cement KW - Concrete KW - Construction PY - 2011 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. SP - 1 EP - 3(?) AN - OPUS4-25156 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Regina A1 - Maierhofer, Christiane A1 - Kreutzbruck, Marc A1 - Schilling, M. T1 - Numerical method of active thermography for the reconstruction of back wall geometry N2 - The paper presents numerical methods to detect and classify defects and inhomogeneities by means of active thermography. The objective is to determine the wall thickness of structure elements with an inaccessible back wall, for example, of pipes or Containers. As test specimens we used approximately 2 cm thick PVC samples with spatial variations in the back wall geometry. Flash lamps provided the heating. To know the thickness of the wall, we used two inversion methods and compared the results achieved. One is an iterative echo defect shape method and already tested on Steel test specimens with good reconstruction results. The second one is the Levenberg-Marquardt method, applied here to thermographic data for non-destructive testing. Since data capturing using active thermography and the presented numerical methods can easily be automated, the combination of these two procedures is a promising approach providing a broad area of application. T2 - 6th Workshop 'NDT in progress' CY - Prague, Czech Republic DA - 10.10.2011 KW - Impulse-thermography KW - Inversion KW - Levenberg-Marquardt method KW - Echo defect shape KW - Defect shape reconstruction PY - 2011 SN - 978-80-214-4339-6 IS - Chapter 8 SP - 245 EP - 252 AN - OPUS4-25144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilder, Constanze A1 - Hofmann, Detlef A1 - Kohlhoff, Harald A1 - Habel, Wolfgang ED - Ramos, G. A. T1 - Structure-integrated fiber-optic strain wave sensor for concrete pile testing and monitoring N2 - Reinforced concrete piles are used in case of structures that are constructed on soft ground to transfer the loads into deeper strata with sufficient bearing capacity. In order to determine the pile’s behavior and possible damage, static and dynamic pile tests are carried out. Dynamic measurements taken from the pile head can show the bearing behavior and structural integrity by using the theory of wave propagation. In order to receive more precise information about the pile features, now, a string of sensors is embedded at different levels of the pile. A fiber optic strain wave sensor, based on the extrinsic Fabry-Perot interferometer (EFPI), has already been developed and tested in full-scale field tests by Schallert (2010). It was possible to detect the introduced deformation caused by the static load and the dilatational wave during dynamic loading. Although the full-scale tests were successful, the engineering design of the sensor body left room - from the economical point of view - to be optimized. After laboratory tests with the optimized sensor, a cast-in-situ bored pile has been built at the BAM Test Site Technical Safety in Horstwalde, South of Berlin. Additionally to the EFPI sensors, fiber Bragg grating (FBG) sensors, temperature sensors and resistance strain gauge (RSG) sensors are embedded in order to compare the signals with each other. In this paper, the modified sensor and the Setup of the cast-in-situ bored pile along with results of dynamic tests are shown. T2 - SHMII-5 - 5th International conference on structural health monitoring of intelligent infrastructure CY - Cancún, Mexico DA - 11.12.2011 KW - Fibre optic sensors KW - Monitoring KW - Concrete pile KW - Foundation KW - Integrity testing PY - 2011 IS - Topic_04.Cat_4.2-abs002 SP - 1 EP - 8 PB - National Autonomous University of Mexico CY - Mexico City AN - OPUS4-25142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grasse, Fabian A1 - Trappe, Volker A1 - Thöns, Sebastian A1 - Said, Samir ED - De Roeck, G. ED - Degrande, G. ED - Lombaert, G. ED - Müller, G. T1 - Structural health monitoring of wind turbine blades by strain measurement and vibration analysis N2 - Wind turbine blades have to withstand a high number of load cycles in mostly hard weather conditions over 20 years. In a research project BAM and several partners have designed, evaluated and tested a condition monitoring system for all parts of a wind turbine. At a rotorblade with a length of 58 m fibre bragg grating sensors were applied for in-service strain measurement. Additionally a complex test rig was designed to enable real biaxial loading conditions at a representative test rotor blade to simulate the mechanical loading conditions in the lab. In this test blade with a length of 8 m also fibre bragg grating sensors were implemented to determine their influences for the structure and the condition monitoring system. Vibration measurements were carried out at different test phases. The results were compared with finite element strain and modal analysis. T2 - EURODYN 2011 - 8th International conference on structural dynamics CY - Leuven, Belgium DA - 04.07.2011 KW - Rotor blade KW - Test blade KW - Modal analysis KW - Condition monitoring PY - 2011 SN - 978-90-760-1931-4 IS - MS25 Tue SP - 3490 EP - 3497 AN - OPUS4-25076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rabe, Torsten A1 - Naghib Zadeh, Hamid A1 - Glitzky, C. A1 - Töpfer, J. T1 - Integration of Ni-Cu-Zn ferrite in LTCC-modules N2 - Integration of magnetic functional components in LTCC Circuit boards calls for co-firing of dielectric and ferrite tapes. Ni-Cu-Zn ferrites with permeability of p=900 were developed which can be fully densified at the Standard LTCC sintering temperature of 900 °C. Successful co-firing of this ferrite with dielectric tapes requires the adaptation of the shrinkage behavior of the materials as well as the thermal expansion during the cooling period - especially in the temperature range below the transformation point of the glassy phase of the dielectric tape. To match these preconditions, a new dielectric LTCC material with steep sintering curve and high thermal expansion coefficient was designed. Sintered multilayer composed of Ni-Cu-Zn ferrite and tailored dielectric tapes are free of cracks and possess no open porosity. No significant interdiffusion between the ferrite and dielectric tapes was found by EDX measurements. Compared to pure ferrite laminates the permeability of co-sintered Ni-Cu-Zn ferrite layers is drastically reduced to 400, i.e. a decrease of more than 50 %. To investigate the origin of this permeability reduction, Ni-Cu-Zn ferrite laminates were sintered separately, and in combination with alumina release tapes or dielectric tapes, respectively. SEM and EDX analysis of co-fired laminates reveal differences in the ferrite grain growth behavior. Ferrite laminates with homogeneous microstructure and grain size up to 50 pm exhibit large permeability. However, growth of ferrite grains does not take place near the interface between ferrite and release or dielectric tapes. There is a strong correlation between high permeability and volume fraction of large ferrite grains. Regions of fine and coarse grains inside the ferrite layers show different bismuth concentration; the Bi-content is larger in regions of fine ferrite grains. T2 - CICMT 2011 - 7th International conference and exhibition on ceramic interconnect and ceramic microsystems technologies CY - San Diego, CA, USA DA - 05.04.2011 KW - LTCC KW - Co-firing KW - Ferrite KW - Shrinkage behavior KW - Constrained sintering KW - Keramische Multilayer KW - Grenzflächenreaktion PY - 2011 SN - 0-930815-92-0 SP - 000266 EP - 000275 PB - IMAPS, International Microelectronics and Packaging Society AN - OPUS4-25072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schurig, Michael A1 - Klinger, Christian A1 - Schöne, Dieter A1 - Bork, Claus-Peter A1 - Klingbeil, Dietmar ED - Christ, H.-J. ED - Berger, C. T1 - Very high cycle fatigue testing on an electrodynamic shaker system N2 - Fatigue testing in the VHCF ränge requires testing machines with increased frequencies. However, application of energy-saving resonance testing leads to a linkage between test frequency and specimen Parameters. The frequency ränge and the available forces of the testing machine are limiting possible specimen dimensions. Electrodynamic shakers combine test frequencies up to 4000 Hz with forces in the kN range. Thus, a relatively wide range of tests is possible which allows studying the influence of specimen size on VHCF behaviour. Electrodynamic shakers as well as the respective Computer control Systems and Vibration measurement techniques are well established in scientific and technical applications. We present results of a first study of VHCF testing on electrodynamic shakers conducted at BAM. Test frequency, specimen size and stress levels have been varied. One goal is to balance the needs of materials testing with the Standard test Systems of environmental Simulation to provide a powerful and flexible tool for very high cycle fatigue testing. Further investigation to optimize the technique is required. T2 - VHCF5 - 5th International conference on very high cycle fatigue CY - Berlin, Germany DA - 28.06.2011 KW - Electrodynamic shaker KW - Resonance testing KW - Variable frequency KW - Envrionmental simulation KW - Specimen size KW - Two-degree-of-freedom system KW - VHCF KW - Shaker KW - Elektrodynamisch KW - Prüfung PY - 2011 SN - 978-3-9814516-0-3 SP - 433 EP - 438 AN - OPUS4-25067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Komann, Steffen A1 - Kiyak, Yusuf A1 - Wille, Frank A1 - Zerbst, Uwe A1 - Weber, Mike A1 - Klingbeil, Dietmar T1 - Assessment of ductile cast iron fracture mechanics analysis within licensing of German transport packages N2 - In the approval procedure of transport packages for radioactive materials, the mechanical and thermal safety assessment is carried out in Germany by competent authority BAM. In recent years BAM was involved in several licensing procedures of new spent fuel and HLW package designs, where the cask body was made of Ductile Cast Iron (DCI). According to IAEA regulations package designs have to fulfill requirements for specific conditions of transport. Type B(U) packages must withstand the defined accident conditions of transport. The temperature range from -40°C up to the operational temperature has to be considered. For the cask material DCI, it is necessary to determine the brittle fracture behavior. The German guideline BAM-GGR 007 defines requirements for the fracture mechanics of DCI. Due to complex structure of the cask body and the dynamic loading a fracture mechanical assessment in an analytical kind is not always possible. Experience of recent design approval procedures show that the application of numerical calculations are applicable to determine the fracture mechanical load in the cask body. At the first step a numerical analysis has to be done to identify the loading state at the whole cask body. Secondly an analysis of a detail of the cask body is made considering the displacement boundary conditions of the global model. An artificial flaw is considered in this detailed model to calculate the fracture mechanical loading state. The finite element mesh was strongly refined in the area of flaw. The size of the artificial flaw is characterized by the ultrasonic inspection used for the quality assurance of the package. The applicant developed additional analysis tools for calculation of stress intensity factor and/or J-Integral. The assessment approach by BAM led to the decision to develop own tools to the possibility for independent check of the results. The paper describes the authority assessment approach for the DCI fracture mechanics analysis. The validation procedure incl. the development of own tools is explained. BAM developed a post-processor called JINFEM to determine the fracture mechanical loads. The regulatory 1 m puncture bar drop test is used to give an example of the assessment procedure. T2 - 52nd INMM Annual meeting CY - Palm Desert, CA, USA DA - 17.07.2011 KW - Mechanische Bewertung KW - Radioaktives Material KW - Numerische Analyse KW - Bruchmechanik PY - 2011 SP - 1 EP - 10 AN - OPUS4-25022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten A1 - Toepfer, J. A1 - Karmazin, R. T1 - Co-firing of LTCC modules with embedded ferrite layers N2 - Further miniaturization of electronic packaging calls for integration of magnetic functional components into LTCC modules. For integration of magnetic function into LTCC, low fired MnZn- and NiCuZn-ferrites which can be fully densified at the standard LTCC sintering temperature of 900°C were developed. To co-fire these ferrite tapes with dielectric tapes the sintering shrinkage and the coefficient of thermal expansion of ferrite and dielectric tapes must be matched. For each ferrite material a new LTCC dielectric material was designed. The embedded ferrite tapes into new LTCC dielectric tapes can be sufficiently densified during co-firing at 900°C without any cracking. Compared to separately sintered ferrites the permeability of embedded ferrite tapes is reduced. For embedded NiCuZn ferrites permeabilities between 230 and 570 (at 2 MHz) according to the thickness of the embedded ferrite layer were measured. For embedded MnZn ferrites a permeability of 300 was measured. T2 - EMPC-2011 - 18th European microelectronics & packaging conference CY - Brighton, UK DA - 12.09.2011 KW - LTCC KW - Co-firing KW - Ferrite PY - 2011 SN - 978-0-9568086-0-8 IS - TuA2 SP - 1 EP - 6 AN - OPUS4-25021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schultz, C. A1 - Schüle, M. A1 - Richter, M. A1 - Pahl, H.-U. A1 - Endert, H. A1 - Bonse, Jörn A1 - Dirnstorfer, I. A1 - Rau, B. A1 - Schlatmann, R. A1 - Quaschning, V. A1 - Fink, F. A1 - Stegemann, B. T1 - P1, P2 and P3 structuring of CIGSe solar cells with a single laser wavelength N2 - Manufacturing of CIGSe thin film solar modules involves typically one laser structuring step (P1) and two mechanical structuring steps (P2 and P3) for serial interconnection. In our approach, complete laser structuring is successfully demonstrated by application of short nanosecond laser pulses (<10 ns) with a single, visible wavelength of 532 nm. The P1 and the P3 trenches are scribed by induced and direct ablation, respectively. For the P2 scribe, the thermal input of the ns laser pulses is used to transform the CIGSe absorber layer locally into a highly conductive compound to provide proper electrical interconnection. These findings promise further simplification and flexibility to thin film solar cell production. T2 - 26th European photovoltaic solar energy conference and exhibition CY - Hamburg, Germany DA - 05.09.2011 KW - Laser processing KW - Nanosecond pulses KW - Ablation KW - Cu(InGa)Se2 KW - Electrical properties PY - 2011 SN - 3-936338-27-2 DO - https://doi.org/10.4229/26thEUPVSEC2011-3AV.1.35 SP - 2540 EP - 2543 AN - OPUS4-24998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, M. A1 - Schultz, C. A1 - Bonse, Jörn A1 - Pahl, H.-U. A1 - Endert, H. A1 - Rau, B. A1 - Schlatmann, R. A1 - Quaschning, V. A1 - Stegemann, B. A1 - Fink, F. T1 - Laser-ablation behavior of thin-film materials used in silicon and CIGSe based solar cells N2 - Structuring of thin-film photovoltaic modules requires basic knowledge of the laser – thin-film interaction in order to adapt the accessible laser parameters, like wavelength, power, repetition rate and scribing speed whilst taking into account the specific material properties of the layer. We have studied the nanosecond laserablation behavior of corresponding layers (i) of silicon based thin-film solar cells with a-Si/µc-Si tandem absorber type and (ii) of back contact and absorber layer of CIGSe solar cells. The respective ablation threshold fluences were determined as integrative parameters describing the specific laser – material interaction. For the threshold determination we used two different methods and developed a new analytical approach taking into account scribing through the glass substrate as it is preferred for most structuring processes. This was done by analyzing the thin film ablation results by means of optical microscopy, profilometry, scanning electron microscopy (SEM). Moreover, we determined the incubation coefficient of the regarded material layers which allows us to predict quantitatively the influence of the spot overlap on the scribing threshold. T2 - 26th European photovoltaic solar energy conference and exhibition CY - Hamburg, Germany DA - 05.09.011 KW - Laser processing KW - Ablation KW - Incubation KW - a-Si/my-Si KW - CIGS PY - 2011 SN - 3-936338-27-2 DO - https://doi.org/10.4229/26thEUPVSEC2011-3DV.2.8 SP - 2943 EP - 2946 AN - OPUS4-24997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberstein, M. A1 - Geier, M. A1 - Grießmann, H. A1 - Partsch, U. A1 - Voelkel, L. A1 - Böhme, R. A1 - Pentzien, Simone A1 - Koter, Robert A1 - Mann, Guido A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Towards an industrial laser doping process for the selective emitter using phosphoric acid as dopant N2 - Different laser supported approaches have already been realized, proving the great potential of laserdoped selective emitters (LDSE). However, it is challenging to establish a low-cost process by using pulsed laser tools. So far a single-step process only leads to satisfying results utilizing cw-lasers. In this paper we have examined a two-step process to produce laser-doped selective emitters on multicrystalline textured standard silicon photovoltaic wafers (90-Ω/sq-Emitter, SiN-antireflection coating (ARC)). The precise ARC removal by near-infrared fs-laser pulses (30 fs, 800 nm), and the doping of uncoated silicon wafers by ns-laser pulses (8 ns, 532 nm) were systematically investigated. In the fs-experiment, optimum conditions for ARC removal were identified. In the nsexperiments under suitable conditions (melting regime), the phosphorous concentration underneath the wafer surface was significantly increased and the sheet resistance was reduced by nearly a factor of two. Moreover, electrical measurements on fired metallization fingers deposited on the laser processed wafers showed low contact resistances. Hence, wafer conditioning with combined fs-laser- and ns-laser-processes are expected to be a promising technology for producing selective emitters. T2 - 26th European photovoltaic solar energy conference and exhibition CY - Hamburg, Germany DA - 05.09.2011 KW - Laser processing KW - Doping KW - Selective emitter KW - Multicrystalline silicon PY - 2011 SN - 3-936338-27-2 DO - https://doi.org/10.4229/26thEUPVSEC2011-2BV.1.2 SP - 1220 EP - 1223 AN - OPUS4-24996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geier, M. A1 - Eberstein, M. A1 - Grießmann, H. A1 - Partsch, U. A1 - Völkel, L. A1 - Böhme, R. A1 - Mann, Guido A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Impact of laser treatment on phosphoric acid coated multicrystalline silicon PV-wafers N2 - The selective emitter is a well-known technology for producing highly doped areas under the metallization grid to improve the solar cell performance. In this work, the influence of laser irradiation on phosphoric acid coated multicrystalline silicon PV-wafers on the wafer surface structure, the phosphorous depth distribution and the electrical contact resistance within the laser treated area as well as the electrical series resistance of laserprocessed solar cells was evaluated. Different laser processing settings were tested including pulsed and continuous wave (cw) laser sources (515 nm, 532 nm, 1064 nm wavelength). Complementary numerical simulations using the finite element method (FEM) were conducted to explain the impact of the laser parameters on the melting behavior (melt duration and geometry). It was found that the melt duration is a key parameter for a successful laser Doping process. Our simulations at a laser wavelengths of 515 nm reveal that low-repetition rate (<500 kHz) laser pulses of 300 ns duration generate a melt duration of ~0.35 µs, whereas upon scanning cw-laser radiation at 532 nm prolongates the melt duration by at least one order of magnitude. Experimentally, the widely used ns-laser pulses did not lead to satisfying laser irradiation results. In contrast, cw-laser radiation and scan velocities of less than 2 m/s led to suitable laser doping featuring low electrical resistances in the laser treated areas. T2 - 26th European photovoltaic solar energy conference and exhibition CY - Hamburg, Germany DA - 05.09.2011 KW - Silicon solar cell KW - Selective emitter KW - Laser processing KW - Doping KW - Simulation PY - 2011 SN - 3-936338-27-2 DO - https://doi.org/10.4229/26thEUPVSEC2011-2BV.1.7 SP - 1243 EP - 1247 AN - OPUS4-24995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Bäßler, Ralph A1 - Otremba, Frank T1 - Use of higher-alloyed metallic materials and duplex steels for transport tanks of dangerous goods N2 - Compatibility evaluations of selected metallic materials under the influence of dangerous goods are published in the BAM-List - Requirements for Tanks for the Transport of Dangerous Goods” as basis for substance-related prototype approvals for tank Containers designed for the carriage of dangerous goods. There is a request of the tank manufacturing industry and transportation Companies to incorporate additional materials into the BAM-List, especially corrosion-resistant materials because of the large number of corrosive dangerous goods. One solution to solve corrosion Problems is to line the tank with a polymer, an alternative solution is the application of high-alloyed stainless steels and nickel-based alloys as there are 1.4529 (XINiCrMoCu 25-20-7, alloy 926), 1.4562 (X1NiCrMoCu32-28-7, alloy 31) and 2.4605 (NiCr23Mo16AI, alloy 59). There is an interest to use cost-efficient steels with high strength values and concomitant adequate corrosion resistance such as duplex steel 1.4362 (X2CrNiN23-4). This steel grade was originally developed as a substitute for the austenitic grades 1.4404 (X2CrNiMo17-12-2) and 1.4571 (X6CrNiMoTi17-12-2). Due to the lower content of the alloy elements nickel and molybdenum this duplex steel is a cost-efficient alternative to molybdenum containing austenite. Due to the limited number of corrosion test results with welded test samples of these high-alloyed materials and the duplex steel under the influence of corrosive dangerous goods a comprehensive test Programme was performed with these materials in Cooperation with ThyssenKrupp VDM and Deutsche Edelstahlwerke GmbH. It can be concluded from the test results that the superaustenitic steels 1.4529 and 1.4562 as well as the nickel-based alloy 2.4605 are a really good alternative as tank materials for the transport of dangerous goods in comparison to the lining of the tanks. The nickel-based alloy 2.4605 shows the best resistance and is suitable as material for tanks transporting all tested corrosive substances. One exception is the temperature limit during the transport of hydrochloric acid. The superaustenit 1.4562 is a resistant material with a wide ränge of application. Exceptions for use are: ammonium bifluoride, brine, 34 % calcium Chloride solution, hydrochloric acid, perchloric acid, 90 % 2-chloropropionic acid, nitrating acid with nitric acid content > 50 % and molten monochloroacetic acid. The alloy is limited suitable for allyl Chloride, aluminum Chloride, copper (II) -Chloride and ferric Chloride. The superaustenit 1.4529 showed the lowest resistance compared to the other two materials. This steel is not resistant in hydrochloric acid, perchloric acid, sodium Chlorite and sodium hypochlorite. The application is limited in the concentration ränge of aqueous Solutions of aluminum Chloride, copper (II) Chloride and ferric Chloride. Due to the reduced alloying content of the duplex steel 1.4362 (X2CrNiN23-4) compared to the austenitic CrNiMo-steels, a lower resistance especially in acidic media like formic, acetic or sulfuric acid was observed. Within the more than 7.000 substances contained in the BAM-List there is a large amount of dangerous goods such as hydrocarbons, alcohols, aldehydes, ketones, ethers, esters, and inorganic alkaline substances which have a large transport volume and do not corrode the duplex steel 1.4362 (X2CrNiN23-4). The test results are included in the actual 11th edition of the BAM-List and therefore available for the costumer. T2 - Stainless steel world conference & exhibition 2011 CY - Maastricht, The Netherlands DA - 29.11.2011 KW - Duplexstahl KW - Tankcontainer KW - Tankfahrzeuge KW - Beständigkeitsbewertung KW - BAM-Liste PY - 2011 SP - 1 EP - 12 PB - KCI Publ. AN - OPUS4-24975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias A1 - Schulz, Sebastian A1 - Stark, Wolfgang A1 - Wolff, Dietmar T1 - Characterization of the low temperature behaviour of rubber sealing materials N2 - Rubbers are often used for seal applications due to their special material properties and easy use. In many applications the material is exposed to low temperatures during Operation. Therefore it is important to know the material behavior at low temperatures to determine the temperature ränge that allows a Safe Operation of the seal, e.g. in storage and transport Containers for radioactive materials. The seal function of an elastomer is limited in temperature by the rubber-glass transition during which the material properties change from rubber-like to stiff and glass-like. For a given application this correlation is not trivial and therefore needs an in-depth investigation under consideration of the physical properties and the application conditions. In this work different analytical methods are used to characterize the material behavior at low temperature in the ränge of the glass-rubber-transition and are compared with the quality of Operation of a component which is here defined by the detected leakage rate. T2 - Technomer 2011 - 22. Fachtagung über Verarbeitung und Anwendung von Polymeren CY - Chemnitz, Deutschland DA - 10.11.2011 PY - 2011 SN - 978-3-939382-10-2 IS - Kap. 3.7 SP - 1 EP - 4 AN - OPUS4-24971 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lenke, Philipp A1 - Wendt, Mario A1 - Krebber, Katerina A1 - Glötzl, R. ED - Bock, W.J. ED - Albert, J. ED - Bao, X. T1 - Highly sensitive fiber optic inclinometer - easy to transport and easy to install N2 - We present the status of our work on a tube shaped 3D deformation sensor based on continuously distributed fiber optic sensing. A sensor tube of very large diameter is used to ensure high sensitivity while the transportability and applicability are still comfortable due to our application strategy. The setup is designed to use different measurement techniques in the applied optical fibers including Brillouin based measurements and interferometric optical frequency domain measurements using an OBR 4400 from Luna Technologies. T2 - 21st International conference on optical fiber sensors (OFS 21) CY - Ottawa, Canada DA - 15.05.2011 KW - Inclinometer KW - Bend KW - Sensor KW - Fiber KW - Optic KW - Brillouin KW - OBR PY - 2011 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 7753 SP - 775352-1 EP - 775352-4 AN - OPUS4-24970 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Perrone, C. A1 - Müller, Urs A1 - Gardei, André A1 - Ziegert, C. ED - Drochytka, R. ED - Bohus, S. T1 - Structural performances of earthen building materials. A comparison between different typologies N2 - Traditional construction techniques utilizing earthen materials are often seen as inferior compared to modern ways of building. Structural earthen elements are perceived as vulnerable towards environmental influences (moisture, frost) and in particular towards the load scenarios during earthquakes. In comparison to the recent advances in research on stone and brick masonry, knowledge on the structural performance of earthen building construction is limited and scattered. Consequently the confidence in the performance of these earthen buildings constructed in the traditional techniques during earthquakes is fairly low. The research presented here aims to make a comparison of mechanical behavior between different earth masonry material typologies, consisting of earth block masonry, rammed earth and cob. The paper has been developed in the framework of a larger research program called NIKER. BAM and other seventeen research partners from the Mediterrean area are jointly involved to develop and validate innovative materials and technologies for the systemic improvement of the seismic behavior of Cultural Heritage assets T2 - 2nd WTA - Internaitonal PhD Symposium - Building materials and buidling technology to preserve the built heritage CY - Brno, Czech Republic DA - 06.10.2011 KW - Earth masonry KW - Material test KW - Mechanical behavior KW - Cultural heritage PY - 2011 SN - 978-3-937066-21-9 SN - 0947-6830 N1 - Serientitel: WTA-Schriftenreihe – Series title: WTA-Schriftenreihe VL - 2 / Part 2 IS - 36 SP - 86 EP - 94 PB - WTA Publications AN - OPUS4-24928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shcheglov, Pavel A1 - Gumenyuk, Andrey A1 - Gornushkin, Igor B. A1 - Rethmeier, Michael T1 - Experimental investigation of the laser-plume interaction during high power fiber laser welding N2 - The effect of the well-known plasma absorption and refraction in CO2-laser metal welding plumes is in case of high power solid state laser welding negligibly small. By contrast, the diffraction effects of shorter wavelength laser radiation are considerable. According to the results of preliminary studies, the fine condensed metal particles in the welding plume can lead to essential worsening of the laser beam quality. This work is devoted to the investigation of the lasermatter interaction during up to 20 kW ytterbium fiber laser welding of thick mild steel plates. The plume attenuation of a probe 1.3 µm wavelength diode laser beam as well as of continuous radiation in 250-600 nm wavelength range was measured during welding with and without Ar shielding gas supply. The measured results allow it to calculate average size and concentration of fine condensed metal particles in different plume areas using the multi-wavelength method and the Mie scattering theory. The plume temperature, which determines the condensation conditions, was measured by means of Fe I atom spectral line emission registration. The obtained results can be also of interest for remote metal treatment with high-power fiber or disc lasers. T2 - 30th ICALEO - International congress on applications of lasers & electro-optics CY - Orlando, FL, USA DA - 2011-10-23 PY - 2011 SN - 978-0-912035-94-9 SP - Paper 1606, 637 EP - 645 AN - OPUS4-24921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Molnarne, Maria A1 - Wilrich, Cordula A1 - Holtappels, Kai T1 - Chemically unstable gases and gas mixtures - new categories in the GHS N2 - In connection with the use of chemically unstable gases (especially acetylene and ethylene oxide) accidents keep on happening - amongst them also quite serious ones. These gases are known to be chemically unstable. A chemically unstable sas is a flammable gas that is able to react exolosivelv even in the absence of air or oxveen. The investigation of accidents showed that the Chemical instability of flammable gases played an important role in the severity of accidents. Therefore, this hazardous property was included in the global harmonizatiön of the Classification of Chemicals. The Classification of chemically unstable flammable gases and mixtures is an amendment to Chapter 2.2 “Flammable gases” of the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS), because most chemically unstable gases are flammable as well. The proposal to add them to the GHS originated from the experts of an informal working group of the UN Sub-Committee of Expert on the GHS (UNSCEGHS) headed by BAM, Germany. The UNSCEGHS has decided to include it in the Fourth Revised Edition of the GHS. The respective method for determining whether a gas is chemically unstable or not, is included in the UN Manual of Tests and Criteria. This paper presents some experimental investigations of these gases, the test methods, examples of new classifications and results from CHEMSAFE T2 - 14th Annual symposium, Mary Kay O´Connor process safety center - Beyond regulatory compliance: making safety second nature CY - College Station, TX, USA DA - 25.10.2011 KW - Chemically unstable gases KW - GHS KW - Chemisch instabile Gase PY - 2011 SP - 871 EP - 882 AN - OPUS4-24913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Urs A1 - Schlegel, Moritz-Caspar A1 - Emmerling, Franziska T1 - Advanced techniques for studying damage mechanisms of cementitious matrices affected by sulfate attack N2 - Cementitious materials, in particular concrete, are durable materials if prepared appropriately and the Service life of concrete structures is now often required to last 120 years or more. Concrete durability depends strongly on intrinsic (e.g. composition, porosity) and exterior factors (e.g. moisture condition and composition, frost cycles, load pattem). Deleterious actions leading to concrete degradation are often created by the environment. Extemal sulfate attack is one of the more spectacular damage scenarios for concrete structures caused by the ingress of sulfate ions into the pore System of the material and successive formation of expanding phases. Though in recent years well studied there are still many questions remaining conceming the mechanisms of sulfate attack. In particular over the last ten years, with the increased utilization of blended cements, new questions arose concerning the sulfate resistance of those binder Systems. In the presented study therefore a method was developed to analyze the changes of the phase composition within the micro structure due to sulfate attack. The analytical method was based on pX-Ray diffraction (pXRD) using Synchrotron radiation in Debye-Scherrer (transmission) geometry. The spatial resolution of the method is ca. 10 pm and allows the characterization of phase transformations in the wake of damaging processes in more detail compared to other techniques. Furthermore, the experimental setup provides the possibility for analyzing the phase assemblage of a given sample without destroying the micro structure. This is possible because the specimens for phase analysis consists of thick sections, which can be used for further microscopic analysis of the micro structure and micro chemistry (e.g. by SEM-EDX). Samples containing supplementary cementitious materials were measured in comparison and to reconstruct the influence of the degradation process in detail. Additionally, reaction ffonts within the samples were localized by micro x-ray fluorescence analysis (MXRF). T2 - EMABM 2011 - 13th Euroseminar on microscopy applied to building materials CY - Ljubljana, Slovenia DA - 14.06.2011 KW - Sulfate attack KW - Concrete KW - Synchrotron KW - XRD KW - Phase analysis PY - 2011 SN - 978-961-90366-7-9 SP - 1 EP - 9 AN - OPUS4-24878 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bachmann, Marcel A1 - Avilov, Vjaceslav A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael T1 - Multiphysics process simulation of the electromagnetic-supported laser beam welding N2 - A three-dimensional laminar steady state numerical model was used to investigate the influence of an alternating current (ac) magnetic field during high power laser beam keyhole welding of 20 mm thick nonferromagnetic aluminum. COMSOL Multiphysics was used to calculate the threedimensional heat transfer, fluid dynamics and electromagnetic field equations. Most important physical effects of the process were taken into account: Thermo-capillary (Marangoni) convection at the upper and lower weld pool boundaries, natural convection due to gravity and latent heat of solid-liquid phase transition. It is shown that the gravity drop-out associated with welding of thick plates due to the hydrostatic pressure can be prevented by the application of an ac magnetic field. The application of an oscillating magnetic field of 70 mT was investigated to allow for singlepass laser beam welding of thick aluminum plates. The flow pattern in the molten zone and the temperature distributions are significantly changed. T2 - COMSOL Conference 2011 CY - Ludwigsburg, Germany DA - 2011-10-26 KW - Electromagnetic weld pool support KW - Laser beam welding KW - Lorentz force KW - Marangoni stresses KW - Natural convection PY - 2011 SN - 978-0-9839688-0-1 IS - 11122 / 8567_bachmann_paper SP - 1 EP - 7 CY - Stuttgart AN - OPUS4-24845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ferraioli, M. A1 - Abruzzese, D. A1 - Miccoli, Lorenzo A1 - Di Lauro, G. T1 - Torsional seismic response of an asymmetric-plan hospital buidling N2 - The inelastic torsional response of an asymmetric-plan hospital building is studied. The response of the structure in the time domain as recorded by highly sensitive sensor network, integrated by a data acquisition system. The identification was performed using techniques of modal extraction in the frequency domain (frequency Domain decomposition). A calibration process was applied in order to identify a reliable structural model to be used for the seismic vulnerability assessment of the hospital building. In particular, a nonlinear static procedure accounting for mass distribution, higher modes contribution and mode-shapes correlation was proposed for the estimation of the seismic response of irregular buildings. Finally, the influence of lateral force distribution, node control during pushover and accidental eccentricity is investigated. T2 - 14th Conference of seismic engineering ANIDIS CY - Bari, Italy DA - 18.09.2011 KW - Seismic response KW - Irregular buildings KW - Inelastic torsion PY - 2011 SN - 978-88-7522-040-2 IS - Abschnitt D SP - 1 EP - 10 AN - OPUS4-24840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ferraioli, M. A1 - Mandara, A. A1 - Abruzzese, D. A1 - Miccoli, Lorenzo T1 - Dynamic identification and seismic safety of masonry bell towers N2 - The paper addresses two case studies of structural monitoring and seismic assessment of medieval masonry Towers in Italy: the bell tower of Aversa and the bell tower of Capua. These monuments in the Campania region were monitored by means of full-scale environmental vibration testing. Measured responses were then used for modal identification. The procedure is based on a typical finite element model updating technique based on vibration test results. Parameters optimization is carried out by minimizing a weighted error criterion relative to the building’s modal properties. A satisfactory improvement on modal parameters is thus obtained, resulting in a close Agreement between the modal properties observed in dynamic tests and those calculated from numerical model. Seismic assessment is carried out with nonlinear static analysis of the tower under multimodal distributions of lateral loads. Nonlinear analysis indicates the potential collapse mechanisms and evidences dangerous structural weakness which may play a role in the seismic vulnerability of the towers. T2 - 14th Conference of seismic engineering ANIDIS CY - Bari, Italy DA - 18.09.2011 KW - Masonry towers KW - Structural identification KW - Model updating PY - 2011 SN - 978-88-7522-040-2 IS - Abschnitt E SP - 1 EP - 10 AN - OPUS4-24839 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramge, Peter A1 - Kühne, Hans-Carsten A1 - Meng, Birgit ED - Drochytka, R. ED - Bohus, S. T1 - Natural stone reprofiling in cultural heritage with modular repair mortars N2 - Whenever the preservation of original substance obtains priority in a restoration task, reprofiling techniques using repair mortars are a welcome solution. For ordinary concrete repair aesthetic aspects are of minor importance whereas for the restoration of natural stone elements they come to the fore. Especially for listed buildings and monuments, historico-cultural and aesthetical interests become the ruling Parameters for planning and execution of restoration tasks. Nevertheless the technical and constructive requirements have to be considered and deterioration processes have to be understood to ensure sustainability and durability of the repair task. Due o differences in the Chemical and mineralogical composition, natural stone provides a vast variety of texture and colour. Also the range of different mechanical and durability related properties is far wider than found with concrete for example. A research project dealing with the development of a modular repair mortar System for natural stone is currently set up at the BAM. To provide the conservator with the best possible options to match colour, texture and technical requirements, the System will be setup on a modular basis. Several different binder Systems on basis of cement, lime and sodium Silicate as well as polymer based Systems are planned, which can be combined with different aggregate compositions and different pigments. To evaluate the mortar performance, test procedures will be defined for tests on mortar samples and on composite specimens. In the paper the experimental Programme will be explained and first results will be presented and discussed. T2 - 2nd WTA - Internaitonal PhD Symposium - Building materials and buidling technology to preserve the built heritage CY - Brno, Czech Republic DA - 06.10.2011 PY - 2011 SN - 978-3-937066-21-9 SN - 0947-6830 N1 - Serientitel: WTA-Schriftenreihe – Series title: WTA-Schriftenreihe IS - 36 SP - 208 EP - 216 PB - WTA Publications AN - OPUS4-24837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Perrone, C. A1 - Müller, Urs A1 - Gardei, André A1 - Ziegert, C. T1 - Comparison of mechanical behavior of different earth masonry typologies in cultural heritage N2 - The paper has been developed in the framework of a larger EC‐research program called NIKER, in which BAM and other seventeen research partners from the Mediterrean area are jointly involved. It aims to develop and validate innovative materials and technologies for the systemic improvement of the seismic behavior of Cultural Heritage assets. The death tolls brought about by recent catastrophes in developing countries where many inhabitants lived in earthen dwellings (Gujarat, India 2001, Bam, Iran 2003 and Concepción, Chile 2010 Earthquakes, Tamil Nadu 2004 Tsunami) have brought about research studies aimed at improving earth construction in terms of strength, seismic resistance and speed of construction. In comparison to the recent advances in research on stone and brick masonry, knowledge on the material properties and failure mechanisms of earthen Building construction is limited and scattered. The research presented here by aims making a comparison of mechanical behaviour between different earth masonry material typologies, consisting of earth block masonry, rammed earth and cob. T2 - WCCE-ECCE-TCCE Joint conference 2 - Seismic protection of cultural heritage CY - Antalya, Turkey DA - 31.10.2011 KW - Earth masonry KW - Material test KW - Cultural heritage KW - Seismic resistance PY - 2011 SN - 978-605-01-0188-1 SP - 25 EP - 36 AN - OPUS4-24836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pistol, Klaus A1 - Weise, Frank A1 - Meng, Birgit A1 - Schneider, U. ED - Koenders, E.A.B. ED - Dehn, F. T1 - The mode of action of polypropylene fibres in high performance concrete at high temperatures N2 - It has been shown in fire tests that polypropylene fibres reduce or avoid explosive spalling of high performance concrete. In the critical temperature ränge up to 300 °C the permeability of HPC increases by using polypropylene fibre. Due to this the water vapour, which is the main reason for explosive spalling, can escape. There exist different theories in the literature conceming the micro structural mechanisms, which cause an increase in the permeability. Within the framework of an internal research project at BAM an innovative methodology was developed for experimental verifying of existing theories and to get new insights into this problem The methodology used is unique and has been undertaken here for the first time. This consists of the combination of acoustic emission and ultrasonic measurement during temperature loading and the non-destructive micro structural analysis of cooled down samples with the aid of micro X-ray computed tomography. For the validation of the nondestructive test methods scanning electron microscopic images of prepared samples were undertaken. The results show that due to the thermal decomposition of the polypropylene fibres micro canals emerge. These are connected due to a simultaneous micro cack formation. T2 - 2nd International RILEM workshop on concrete spalling due to fire exposure CY - Delft, The Netherlands DA - 05.10.2011 KW - Spalling KW - Polypropylene fibres KW - High performance concrete KW - Acoustic emission KW - X-ray computed tomography KW - Scanning electron microscopy PY - 2011 SN - 978-2-35158-118-6 SP - 289 EP - 296 PB - RILEM Publications AN - OPUS4-24835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wosniok, Aleksander A1 - Krebber, Katerina T1 - Simultaneous measurement of temperature and strain distribution using Brillouin scattering in dispersion-shifted fibers N2 - We studied Brillouin gain spectrum characteristics in dispersion-shifted fibers having compound GeO2-doping compositions in the fiber core to realize simultaneous measurement of distributed strain and temperature. Due to various dopant concentration alongside the radius of tested nonzero dispersion-shifted fibers several multiple Brillouin scattering resonances were observed in the stimulated Brillouin spectra arose through backscattering on higher acoustic modes which propagated along the fiber axis. As a result of the varying acoustic velocities, the Brillouin resonance peaks featured different temperature coefficients which can be used to accomplish the simultaneous measurement of fiber strain and temperature. We presented our first measurement results for NZDS Fujikura and LEAF Corning fiber and discussed the superior sensory suitability of the former fiber types. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.10.2011 KW - Fiber optic sensor KW - Spatial distributed sensor KW - Brillouin gain spectrum (BGS) KW - Nonzero dispersion-shifted fiber (NZDSF) KW - Brillouin sensor KW - BOTDA KW - BOFDA PY - 2011 SN - 978-1-4244-9288-6 SP - 1476 EP - 1479 AN - OPUS4-24828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pereira, F. A1 - Pistol, Klaus A1 - Korzen, Manfred A1 - Weise, Frank A1 - Pimienta, P. A1 - Carré, H. A1 - Huismann, Sven ED - Koenders, E.A.B. ED - Dehn, F. T1 - Monitoring of fire damage processes in concrete by pore pressure and acoustic emission measurements N2 - This paper presents the combined use of acoustic emission (AE), gas pore pressure and temperature measurements (PT). The simultaneous application of both techniques represents a new methodology in the context of fire spalling and contributes to a better understanding of the mechanisms of fire spalling, particular with regard to the interaction of micro cracking and pore pressure evolution. The study presents fire tests on normal strength concrete specimens with and without reinforcement at ISO Standard fire and at hydrocarbon (HC) fire. Supported by AE-analysis, it can be shown that due to the higher heating rate of the HC-fire in comparison to the ISO Standard fire the damage processes inside the concrete during the exposure are increased combined with augmenting the concrete permeability. As a consequence lower pore pressures were measured. However, despite the lower pore pressures, explosive spalling was observed. T2 - 2nd International RILEM workshop on concrete spalling due to fire exposure CY - Delft, The Netherlands DA - 05.10.2011 KW - Ordinary concrete KW - High temperature KW - Gas pore pressure KW - Acoustic emission KW - Spalling PY - 2011 SN - 978-2-35158-118-6 SP - 69 EP - 77 PB - RILEM Publications AN - OPUS4-24818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chabrelie, A. A1 - Müller, Urs A1 - Scrivener, K.L. ED - Palomo, Á. ED - Zaragoza, A. ED - Agüí, J. C. L. T1 - Mechanisms of degradation of concrete by external sufate ions under laboratory and field conditions N2 - The durability of concrete is a major challenge for the construction, which devotes one third to one half of its annual investment to building maintenance. The lack of fieid data regarding concrete durability, especially in the case of exposure to Sulfate ions (“sulfate attack”) makes it dijficult to determine the appropriate fest methods andperformance criteria. Additionally, the increased use of sustainable blends (cement with mineral admixtures, typically slag from the iron industiy) suffers from a lack of experience regarding their long-term performance. Most results for sulfate resistance are derived from accelerated laboratoiy tests xvhere performance criteria are based only on macroscopic properties, especially expansion. To fill this gap and better widerstand the mechanisms of sulfate attack under real conditions, a parallel study of laboratoiy micro-concrete and fieid concrete samples under sulfate exposure was undertaken, focussing on microstructural changes in addition to the conventional macroscopic characterisation. Four exposure regimes were designed in the laboratoiy: full immersion (ponding), pH-control, semi-immersion and wet/diy cycles. Pure Portland blends and slag blends witli high level of slag replacement (70 wt.-%) were investigated. The exposure regime has been found to play a major role in the damage process. In ponding conditions, the damage process takes place in three stages characterised by a first period of induction, followed by surface damage thatfinally extends to the bulle of the material. Paradoxically, the w/c-ratio does not seem to have much impact on the ionic transport phenomena but might be more decisive in the microstructure mechanical strength against local stresses. The slag blends, considered as sulfate resistant in ponding exposure, revealed badperformances under wet/diy cycles. This beliaviour was attributed to poor proper physical resistance of the slag hydrates against diying. The fieid concretes selected for the comparison with the laboratoiy cases were partially buried in a sulfate-enriched soil in Argentina. A pure Portland blend and a slag blends with high level of slag replacement (80 wt.-%) were investigated. The submerged part of the samples could be compared to the laboratoiy ponding exposure, wliile the upper layer of the samples subjected to weathering could be compared to the laboratoiy wet/diy cycles exposure. The fieid obsen’ations tend to confirm the laboratoiy results and validate the fest settings. It has been underlined that a direct relationship between damage (e.g.; cracking/expansion) andphase assemblage was not evident. However, the study highlights that sulfate combination with the hydrates of the cement (e.g.; C-S-H) and with those of the slag would play a rote in the initiation of the expansion, which would be attributed to a swelling of the hydrates or to the precipitation offine ettringite after the Saturation level in sulfate of the hydrates has been reached. T2 - 13th International congress on the chemistry of cement - XIII ICCC CY - Madrid, Spain DA - 03.07.2011 KW - Sulfate attack KW - Exposure conditions KW - Concrete KW - Laboratory test KW - Field KW - Phase assemblage KW - Microstructure KW - XRD KW - SEM KW - SCM KW - Slag PY - 2011 SN - 978-84-7292-400-0 SP - 1 EP - 14 CY - Madrid AN - OPUS4-24810 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir ED - Zhai, W. ED - Takemiya, H. ED - De Roeck, G. ED - Tutumluer, E. T1 - Experimental soil parameters by different evaluation methods for impulsive, train and ambient excitation T2 - ISEV 2011 - 5th International symposium on environmental vibration - Advances in environmental vibration CY - Chengdu, China DA - 2011-10-20 KW - Wave velocity KW - Dispersion KW - SASW KW - MASW KW - SPAC KW - Damping PY - 2011 SN - 978-7-03-032373-6 SP - 3 EP - 9 PB - Science Press AN - OPUS4-24807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Náprstek, J. ED - Horácek, J. ED - Okrouhlík, M. ED - Marvalová, B. ED - Verhulst, F. ED - Sawicki, J.T. T1 - Reducing ground-borne micro-vibrations by plate foundations T2 - Vibration problems ICOVP 2011 - 10th international conference on vibration problems CY - Prague, Czech Republic DA - 2011-09-05 KW - Plate-soil interaction KW - Wave excitation KW - Vibration reduction KW - Finite-element boundary-element method PY - 2011 SN - 978-94-007-2068-8 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics VL - 139 SP - 329 EP - 335 PB - Springer AN - OPUS4-24804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gümpel, P. A1 - Leu, F. A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Corrosion resistance of lean alloy alternatives for 300 series stainless steels N2 - Rising Prices of nickel and molybdenum in the past few years have led to unprecedented interest in Substitution of leaner-content alloys for Standard 300-series austenitic stainless steels in a lot of applications. Due to the high prices of different alloying elements and to periodic large fluctuations that cause similar large fluctuations in the costs of using 300-series stainless steels; a lot of new materials entered the markets in Europe and also in the rest of the world. A big disadvantage consists in the fact that there are though corrosion results that, however, a direct comparison of the corrosion resistance of these new materials does not exist up to now or only incompletely. In this project comparative investigations were carried out and always one or several representatives of a material group were incorporated. These material groups are: Lean Duplex Stainless Steels, Manganese Alloyed Austenitic and Duplex Stainless Steels and Ferritic Stainless Steels. These materials were investigated in a lot of different test procedures and in different conditions focused on the application in civil engineering and common use. Beside the electrochemical investigations all materials were exposed in different surface States in the atmosphere, once in Coastal nearness and once in a city centre area. Other exposition tests with material Coupons where done in the atmosphere of indoor swimming pools and at the case of food processing machines were corrosion processes are caused by the cleaning procedure. First results are reported. T2 - 7th European stainless steel conference - science and market CY - Como, Italy DA - 21.09.2011 KW - Austenitic stainless steels KW - Ferritic stainless steels KW - Duplex stainless steels KW - Manganese alloyed stainless steels KW - Pitting corrosion KW - Stress corrosion cracking KW - Passive layer KW - Surface condition PY - 2011 SN - 978-88-85298-84-2 IS - Applications / No. 53 SP - 1 EP - 15 AN - OPUS4-24803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herbst, Tristan A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. T1 - Sustainable evaluation - concept to assess the applicability of secondary aggregates in concrete N2 - Nowadays there are several applications of mineral recycling materials and residues. At present an assessment method for the use of secondary raw materials, which considers sustainability aspects, does not exist. In the framework of the German DAfStb/BMBF research project “Sustainable Building with Concrete” an assessment concept was developed. It includes the following four assessment steps: I. Basic considerations, II. Advantages for sustainable construction, III. Alternative paths for application, and IV. Sensitivity analysis. The concept was developed on the basis of recycled concrete aggregates, which are already used according to German standards. Afterwards, it was applied and verified by the evaluation of the utilisation of municipal solid waste incinerator bottom ashes (referred to MSWI bottom ashes). T2 - 2011 Helsinki world sustainable building conference CY - Helsinki, Finland DA - 18.10.2011 KW - Sustainable building KW - Sustainability aspects KW - Secondary materials KW - Secondary aggregates in concrete KW - Energy and material resources KW - Assessment concept PY - 2011 SN - 978-951-758-534-7 SN - 0356-9403 SP - 1 EP - 8 AN - OPUS4-24781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram T1 - Challenges of the African environmental conditions for concrete mixture composition N2 - Concrete technology was exposed to a rapid development during the last three decades. For the longest time in its history, concrete was considered as a three component System consisting of aggregates, which are bound by the hardened cement paste consisting of hydrated cement. Traditionally, the only way of adjusting the consistency of concrete was using well adjusted aggregates and grading curves and adding excess water to the concrete, accepting that the latter in return reduces strength and durability. During the last three decades, however, concrete has developed further from a three component System towards an (at least) five component system, since the use of mineral additions and Chemical admixtures has become state of the art. Both components are able to enhance the workability, the compactability, and the density of the microstructure with effects on strength, ductility and durability, while cement can be saved in parallel. Due to reasonable use of admixtures and additions, concrete can be designed to match mechanically high performance specifications. Traditionally, cement paste was considered the weakest component in concrete. Flowever, in modern concrete a good paste composition can yield highest performance, passing the role of the mechanical bottleneck towards the aggregates. T2 - Workshop cement and concrete for Africa CY - Berlin, Germany DA - 17.08.2011 KW - Cement KW - Concrete KW - Mixture composition KW - Africa KW - Climatic conditions PY - 2011 SN - 978-3-9814281-4-8 SP - 37 EP - 49 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-24780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Taffese, W.Z. A1 - Kumaran, G.S. A1 - Uzoegbo, H.C. A1 - Kühne, Hans-Carsten T1 - Inorganic binder systems for innovative panel technology in East Africa - possible ways to produce building materials from local raw materials N2 - Many African countries face serious problems associated with the rapid growth of urban Population and the resulting demand for affordable building materials. In search for appropriate Solutions to improve the Situation, the “LightSHIP” project was initiated, whose aims were to identify the required product specifications, to evaluate possible approaches and ultimately to develop new Building materials for East Africa. It was concluded that these materials should be produced in Africa mainiy from local raw materials; prefabricated, easily transportable construction elements are to be preferred. It is therefore reasonable to focus on artificial stones and partition boards. To be Independent of imported cement, it is suggested to make use of volcanic rocks, which are abundant in East African countries, for lime-pozzoian binders and geopolymers in the production of these construction elements. Future research activities should thus concentrate on assessment of the applicability of available volcanic rocks, the influence of their properties on the resulting binders and the design of appropriate binder-reinforcement-filler Systems. T2 - Workshop cement and concrete for Africa CY - Berlin, Germany DA - 17.08.2011 KW - Building materials KW - East Africa KW - Volcanic rock KW - Natural pozzolans KW - Lime-pozzolan binders KW - Geopolymers PY - 2011 SN - 978-3-9814281-4-8 SP - 32 EP - 36 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-24779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Priebe, Nsesheye Susan A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten T1 - The SPIN project N2 - Globally, cement and concrete experts are at the cutting-edge to sustainable, green, healthy but nonetheless high-performance concrete. In the present age, concrete is not yet well established in Africa, which öfters the unique opportunity to build up a cement and concrete market based on the highest available state of technology. As this industry needs high level expertise, a central issue in implementation of skilled technology is cross-linking research institutions and laboratories. It should not be neglected that concrete is a product with comparably low transport ranges, which means that an improved concrete market will mainly support the local economy without exceeding financial drains to the international market, thus fostering the fight against poverty, which is an urgent need in most African countries. The SPIN project highlights recent developments in the field of cement and concrete research with impact on the local and global economy. Challenges, future developments and opportunities for the African construction industry are in the focus. The SPIN project is funded by the European Commission (EC) and supported by the African, Caribbean and Pacific (ACP) Group of States under the project body of the ACP Science and Technology Programme. SPIN is acronym for “Spearhead network for Innovative, Clean and Safe Cement and Concrete Technologies”. The project aims to cross-link experts with industry and policy making bodies, aiming to establish sustainable cement and concrete construction in Africa. T2 - Workshop cement and concrete for Africa CY - Berlin, Germany DA - 17.08.2011 PY - 2011 SN - 978-3-9814281-4-8 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. SP - 5 EP - 9 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-24778 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - Combustion of peroxy-fuels N2 - The diffusion flames of organic peroxides exhibit quite different characteristics than hydrocarbons. What makes them interesting to study is their fast burning behaviour. As a result the flame temperature enhances and so does the thermal radiation. Due to all these they demand safe handling during processing. However, they can be utilised at several places in different industries where a fuel with fast burning, high temperature and intense radiation are desired. Some of the possibilities to use them as a main or supporting fuel in a wide range of industrial utilities are the major content of this paper. T2 - ERCOFTAC conference - Highly resolved experimental and numerical diagnostics for turbulent combustion CY - Rouen, France DA - 25.05.2011 KW - Energetic materials KW - Process industries KW - Organic peroxide KW - Di-tert-butyl peroxide (DTBP) KW - CFD simulation KW - Emission PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-247083 SP - 1 EP - 5 AN - OPUS4-24708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - An efficient and clean fuel for high temperature process industries N2 - The use of energetic materials as a main fuel in high temperature process industries are not known to the scientific community as such. This paper highlights some of the features and advantages of using organic peroxides especially di-tert-butyl peroxide (DTBP) in high temperature process industries. The feasibility of using DTBP as a main or supporting fuel in process industries have also been justified with the help of Computational Fluid Dynamics (CFD) simulations. For peroxides requirement of less fuel and air for the same amount of heat flux has been shown. The resulted emission from the combustion of DTBP is also discussed. T2 - 11th Conference on Energy for a Clean Environment CY - Lisbon, Portugal DA - 2011-07-05 KW - Energetic materials KW - Process industries KW - Organic peroxide KW - Di-tert-butylperoxide (DTBP) KW - CFD simulation KW - Emission PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-247071 SP - 1 EP - 10 AN - OPUS4-24707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholz, Christian A1 - Woydt, Mathias T1 - Highly stressable and low friction slip-rolling contacts through thin film coatings, uncoated, alternative steels or lubricants N2 - OEMs perceive diamond-like carbon (DLC) coatings as part of a strategy for low frictional tribosystems. Especially the automotive industry anticipates a benefit in applying such coatings in association with the lightweight construction of mechanical parts, for instance in gears and engines. In previous investigations it was shown, that DLC, amorphous carbon (a-C) and tetragonal amorphous carbon (ta-C) coatings can be slip-rolling resistant at least up to ten million load cycles at Hertzian contact pressures P0max of 2.9 GPa lubricated by engine oil at 120°C, Further improvements in load carrying capacity up to P0mean of 2.62 GPa (FN= 5,000 N) were achieved with alternative, available Steel metallurgies as Substrates for thin film coatings. Additional factors, such as influences of the lubrication on the surface chemistry (additives and base oils), wear and friction behavior were investigated. T2 - International tribology conference 2011 CY - Hiroshima, Japan DA - 30.10.2011 KW - Slip-rolling KW - Additives KW - DLC KW - ZrCN KW - High toughness steel KW - High pressure PY - 2011 IS - B4-08 SP - 1 EP - 1 AN - OPUS4-24702 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ferrero, Fabio A1 - Kluge, Martin A1 - Schröder, Volkmar T1 - Numerical analysis of the effect of the electrode distance during the determination of the flammability limits of gases N2 - COMSOL Multiphysics® was used as a tool for the better understanding of the evolution of flow patterns during the induced ignition of gases. A simplified model was developed for the scope, by coupling the weakly compressible Navier Stokes module and the convection and conduction module. The current paper presents the results of the performed simulations. T2 - COMSOL Conference 2011 CY - Ludwigsburg, Germany DA - 26.10.2011 KW - Spark ignition KW - Gas flow KW - Temperature PY - 2011 SN - 978-0-9839688-0-1 N1 - Geburtsname von Kluge, Martin: Beckmann-Kluge, M. - Birth name of Kluge, Martin: Beckmann-Kluge, M. SP - 1 EP - 7 CY - Stuttgart AN - OPUS4-24700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stoppel, Markus A1 - Kurz, J.H. A1 - Taffe, Alexander A1 - Boller, C. ED - Chang, F.-K. T1 - Proactive condition assessment in civil engineering using automated multi-sensor systems N2 - Infrastructure is subject to continuous ageing. This has given life cycle management of infrastructure an increasing role. Reliable inspection and monitoring tools are therefore an increasing demand. A combination of different non-destructive test methods is often necessary to receive reliable results for material characterization, flaw detection and the determination of component specific geometry parameters. Regarding concrete structures thickness measurements are combined with flaw detection and additional information about reinforcement and tendon ducts is required. Therefore, a multi-sensor measurement approach is necessary with a high degree of automation. Otherwise a time consuming succession of manual measurements has to be performed which would prevent practical applications. A modular control and data acquisition approach is described and the application of two different automated measurement devices is shown. The BetoScan system consists of a self-navigating mobile robot. The system is especially designed for the investigation of reinforced concrete floors exposed to de-icing salts. The data acquisition of the OSSCAR system a multi-sensor scanner is similar to the robot approach. These different applications are based on a similar kernel allowing the modular use of different contact and noncontact sensors. The described general concept of multi-sensor data acquisition and data analysis presented here is not limited to the field of civil engineering applications. T2 - 8th International workshop on structural health monitoring 2011 CY - Stanford, CA, USA DA - 13.09.2011 KW - Multi sensor KW - Data acquisition KW - Assessment of concrete structures KW - Scanner KW - NDT PY - 2011 SN - 978-1-60595-053-2 VL - 2 SP - 2359 EP - 2366 PB - DEStech Publications, Inc. AN - OPUS4-24692 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Döhler, M. A1 - Mevel, L. A1 - Rücker, Werner ED - De Roeck, G. ED - Degrande, G. ED - Lombaert, G. ED - Müller, G. T1 - Subspace-based damage detection methods on a prestressed concrete bridge N2 - For the last decades vibration based damage detection of engineering structures has become an important issue for maintenance operations on transport infrastructure. Research in vibration based structural damage detection has been rapidly expanding from classic modal parameter estimation to modern operational monitoring. Methodologies from control Engineering especially of aerospace applications have been adopted and converted for the application on civil structures. Here the difficulty is to regard to the specific environmental and operational influence to the structure under observation. A null space based damage detection algorithm is tested for its sensitivity to structural damage of a prestressed concrete road bridge. Specific techniques and extensions of the algorithm are used to overcome difficulties from the size of the structure which is associated with the number of recorded sensor channels as well as from the operational disturbances by a nearby construction site. It can be shown that for concrete bridges the proposed damage detection methodology is able to clearly indicate the presence of structural damage, if the damage leads to a significant change of the structural system. Small damage which do not result in a System change when not activated by loading, do not lead to a modification of the dynamic response behavior and for that cannot be detected with the proposed global monitoring method. T2 - EURODYN 2011 - 8th International conference on structural dynamics CY - Leuven, Belgium DA - 04.07.2011 KW - Subspace methods KW - Fault detection KW - Monitoring techniques KW - Concrete bridge PY - 2011 SN - 978-90-760-1931-4 IS - MS12 TUE 11:45 SP - 2304 EP - 2310 AN - OPUS4-24689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döhler, M. A1 - Hille, Falk A1 - Mevel, L. A1 - Rücker, Werner ED - Chang, F.-K. T1 - Structural health monitoring during progressive damage test of S101 bridge N2 - For the last decades vibration based identification of damage on civil Engineering structures has become an important issue for maintenance operations on transport infrastructure. Research in that field has been rapidly expanding from classic modal Parameter estimation using measured excitation to modern operational monitoring. Here the difficulty is to regard to the specific environmental and operational influence to the structure under observation. In this paper, two methods accounting for statistical and/or operational uncertainties are applied to measurement data of a progressive damage test on a prestressed concrete bridge. On the base of covariance driven Stochastic Subspace Identification (SSI) an algorithm is developed to monitor and automatically compute confidence intervals of the obtained modal parameters. Furthermore, a null space based non-parametric damage detection method, utilizing a statistical χ2 type test is applied to the measurement data. It can be shown that for concrete bridges the proposed methodology is able to clearly indicate the presence of structural damage, if the damage leads to a change of the structural system. T2 - 8th International workshop on structural health monitoring 2011 CY - Stanford, CA, USA DA - 13.09.2011 KW - Subspace identification KW - Damage detection KW - Convidence intervals KW - Prestressed concrete bridge PY - 2011 SN - 978-1-60595-053-2 VL - 1 SP - 748 EP - 758 PB - DEStech Publications, Inc. AN - OPUS4-24688 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - CFD simulation to predict the thermal radiation of large LNG pool fires N2 - Flame temperature (T), surface emissive power (SEP) of Liquefied Natural Gas (LNG) pool fires (d = 1 m, 6.1 m, 30 m) are investigated by CFD (Computational Fluid Dynamics) simulation and compared with experimental results. Time averaged flame temperatures of T = 1320 K, T = 1298 K and T = 1281 K are obtained. Surface emissive power (SEP) of 55 kW=m2, 130 kW=m2 and 230 kW=m2 are predicted. T2 - 5th European combustion meeting 2011 CY - Cardiff, UK DA - 28.06.2011 KW - Pool fire KW - LNG KW - CFD KW - Thermal radiation KW - Surface emissive power PY - 2011 SP - 1 EP - 6 AN - OPUS4-24687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Interpretations of temperature measurements in organic peroxide pool fires N2 - Most of the measurements of temperatures in large pool fires are indirect and present a number of complexities due to the interactions of convection, radiation and soot blockage. In the present work these influences for two organic peroxide [tert-butyl peroxybenzoate (TBPB) and tert-butyl peroxy-2-ethylhexanoate (TBPEH)] pool fires are analysed. Thermocouple measured temperature in the clear flame zone i.e. combustion zone are found to be 250-400 K lower than from the thermographic measurements. The convective and radiative heat flux contributions from the fire on temperature measurements are discussed. CFD (Computational Fluid Dynamics) simulations have been performed for large pool fires and the predicted time averaged flame temperatures were found to be in qualitative agreement with measurements due to the stoichiometric combustion model used in the present simulations. T2 - 5th European combustion meeting 2011 CY - Cardiff, UK DA - 28.06.2011 KW - Pool fire KW - Organic peroxides KW - TBPB KW - TBPEH KW - CFD KW - Temperature measurement PY - 2011 UR - http://www.uni-due.de/tchem/as/skripte/paper_mishra_et_al_cardiff_2011.pdf SP - 1 EP - 5 AN - OPUS4-24686 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nöther, N. A1 - Krebber, Katerina A1 - Schneider-Glötzl, J. T1 - An all-digital implementation of the Brillouin optical frequency domain analysis for long-range distributed strain and temperature monitoring N2 - For long-range measurements in geotechnical and industrial applications, distributed optical fiber sensors have become a tool of increasing importance throughout the past decade. Classic deformation monitoring (performed by strain gauges etc.) and temperature monitoring (Pt100 and alike) deliver data from fixed, single spots of a structure; quasidistributed measurements (fiber bragg gratings) provide a Chain of discrete measurement points along a limited sensing length. In contrast, an opticai fiber connected to a device for distributed strain and temperature sensing (DTSS) will provide a continuous profile of strain and temperature - spatially resolved down to less than 1 m - over a ränge of several tens of kilometers. In DTSS measurements, the nonlinear opticai effect of stimulated Brillouin Scattering (SBS) is employed: two light waves with a stable, tunable frequency offset are injected into opposite ends of the sensing fiber, where they will form a beat pattem, at which parts of the light will be scattered. By matching the frequency offset of the light waves to the propagation of acoustic fluctuation in the opticai fiber, a power transfer from one light wave to the other can be measured; since the acoustic propagation directly shifts with train and temperature of the fiber, these two quantities can be measured by tuning the light waves’ frequency offset. T2 - 8th International symposium on field measurements in geomechanics - FMGM 2011 CY - Berlin, Germany DA - 12.09.2011 PY - 2011 SP - 1 EP - 6 AN - OPUS4-24664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Tkachenko, Viktoriya T1 - How do application-related issues influence the reliability of fiber optic strain measurements? N2 - Fibre optic strain sensors are increasingly used and sensor systems are provided with specifications. Even if the performance is well specified, the strain characteristics of the sensor, strain transfer factor, mechanical stability under thermal influences, the performance of applied strain sensors can seriously differ from virgin sensor's the performance. The contribution will focus on issues that can deteriorate the sensor function or reduce the reliability of measurement results. Aspects are considered how to come to reliable strain measurements and how to validate strain measurements of applied sensors. Related to this topic, European activities like the recently started European COST TD1001 action, called (OfSeSa) will be presented. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.11.2011 KW - Fibre optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application reliability PY - 2011 SN - 978-1-4244-9288-6 SP - 947 EP - 950 AN - OPUS4-24656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Kusche, Nadine T1 - Calibration facility for quality certification of surface-attached fiber optic and electrical strain sensors N2 - Strain measurement in structures witli the purpose of long-term structurai health inonitoring must provide reliable inforination about the structure’s behavior over the whole period of use. The user must be sure that installed sensors are validated and work to the utmost satisfactiou. For this purpose, sensor Systems are tested using special facilities. Bccause it is not easy to characterize the strain transfer quality from the host structure into surface-applied strain sensors, a unique testing facility has been developed. Originally developed for fiber Bragg grating based sensors, the KALFOS facility (= calibration of fiber optic sensors) can also be used for electrical strain sensors. Calibration ineasurements are referenced by unbinsed Digital Image Correlation (D1C) and Electronic Speckle Pattern Interferometer (ESPI) methods. The strain transfer behavior can experimentally be analyzed and investigated under combined thermal and mechanical loading conditions and allows revealing wealuiesses in couimonly used attachment methodologies. The deformation of all members (particularly the coating/substrate - adhesive combination) in the sensing area is physically independently gained and recorded. Results achievcd allow precise description of the strain transfer function, Validation of the longterm strain sensor characteristics, matching of specific measurement requirements with environmental conditions, and, moreover, the verification of Standards for use of strain sensors. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.10.2011 KW - Fibre optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application reliability PY - 2011 SN - 978-1-4244-9288-6 DO - https://doi.org/10.1109/ICSENS.2011.6127253 SP - 1337 EP - 1340 AN - OPUS4-24655 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seefeldt, Henrik A1 - Braun, Ulrike A1 - Hofmann-Böllinghaus, Anja T1 - Influence of structure, wood content, moisture and additives on the burning behaviour of wood plastic composites T2 - Fire and materials 2011 - 12th International conference and exhibiton CY - San Francisco, CA, USA DA - 2011-01-31 PY - 2011 SP - 1 EP - 10 PB - Interscience Communications AN - OPUS4-24650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Kusche, Nadine A1 - Münzenberger, Sven A1 - Schukar, Vivien T1 - KALFOS - a validation facility for strain transfer characterization of surface-applied strain sensors N2 - Strain sensors embedded in or attached to structural components have to measure the real deformation of the structure over the whole period of use. The user must know how reliably installed sensors provide strain measurement results. For this purpose, test facilities or coupon tests are used. In order to characterize the strain transfer quality from the host structure into surface-applied strain sensors, a unique testing facility has been developed. This facility can be used both for fiber optic and resistance strain sensors. Originally developed for fiber Bragg grating based sensors, the KALFOS facility (=calibration of fiber optic sensors) uses Digital Image Correlation (DIC) and Electronic Speckle Pattern Interferometer (ESPI) as unbiased referencing methods. It is possible to determine experimentally the strain transfer mechanism under combined thermal and mechanical loading conditions. This experimental characterization method will reveal weaknesses in commonly used strain sensors, and the investigation of the material systems used for fiber optic and other strain sensors (particularly the coating/substrate - adhesive combination). The KALFOS facility allows matching of specific measurement requirements with environmental conditions. T2 - SAE 2011 AeroTech Congress & Exhibition CY - Toulouse, France DA - 18.10.2011 KW - Fiber optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application PY - 2011 DO - https://doi.org/10.4271/2011-01-2606 IS - Paper 2011-01-2606 SP - 1 EP - 7 AN - OPUS4-24643 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ehlig, D. A1 - Hothan, Sascha ED - Koenders, E.A.B. ED - Dehn, F. T1 - Reinforced concrete slabs strengthened with textile reinforced concrete subjected to fire N2 - Thin layers of textile reinforced concrete (TRC) can be used as strengthening for reinforced concrete (RC) slabs or beams to increase their foad-bearing capacity. The concrete matrix consists of a fine-grained concrete with a thickness of 8 to 15 mm. Information on the behaviour of strengthened structures subjected to fire is of particular inlerest for practical applications of this innovative construction method. A total of 7 RC slabs with Steel reinforcement were produced: 2 slabs were used as reference and 5 slabs were strengthened with three layers of textile reinforcement. Ultimate capacity of reference slabs and particular TRC strengthened slabs was determined from statie load results fom 4-point-bending tests. Fire tests on these slabs were carried out with utilization fectors using a Standard temperature curve (ISO-834-1) for fire testing. Test loads varied between 0 % and 65 % ofuMmate load. To detect temperatures during fire exposure thermocouples were arranged throughout the cross-section of the slabs. Depending on the utilization the slabs were exposed to fire for 30 minutes or for 60 minutes. In some cases bending fäilure occurred, in other cases the slabs survived. None of the specimens exhibited any visual damage or concrete spalling during fire exposure. Results of deformation measurements and residual strength measurements are presented. Even though mechanisms are not fifily understood, it is important to discuss the presumable reasons for the surprisingiy positive test results. It is presumed tbat the key mechanisms contributing to the outstanding fire resistance capability presented are: superior crack control of the TRC and load redistribution between textile and Steel reinforcement as well as the primary load transfer directly into the slabs. T2 - 2nd International RILEM workshop on concrete spalling due to fire exposure CY - Delft, The Netherlands DA - 05.10.2011 KW - Textile reinforced concrete KW - Fine-grained concrete KW - Carbon fibres KW - Bending load KW - Fire exposure PY - 2011 SN - 978-2-35158-118-6 VL - PRO 80 SP - 419 EP - 426 PB - RILEM Publications AN - OPUS4-24636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -