TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Müller, Maximilian A1 - Mieller, Björn T1 - RFID sensor systems embedded in concrete – validation experiments for long-term monitoring N2 - Structural Health Monitoring (SHM) is an important part of buildings surveillance and maintenance to detect material failure as early as possible and to contribute in protection of structures and their users. The implementation of Radio Frequency Identification (RFID) sensor systems without cable connection and battery into building components offers innovative possibilities to enable long-term in-situ SHM of addressed structures, bridges. The objectives of the presented study are complete embedding of RFID sensors systems in concrete, full passive communication with the systems, at best for the whole life span of structures. One challenge for this task is the highly alkaline environment in concrete, which requires non-degrading and robust encapsulation. Further Requirements are passive communication and energy supply, appropriate antenna design, placement and fixation in concrete, and the selection and implementation of sensors and connections. The concept is to develop and optimize a simple and robust system, which meets the requirements, as well as comprehensive validation in concrete specimen and real world applications. Two different systems were developed (HF and UHF RFID, respectively). First tasks were the implementation of analog sensors using the superposition principle for the signal adaption. Investigation of suitable materials for robust encapsulation and sensor protection against basic environments. Four materials were investigated in pH 13 solution for 14 days - 3D-Printer-Polymer was completely resolved - PVC has no noticeable decrease in weight - (VitaPro) glass filter for the sensor protector, has weight loss 2.7 % - The epoxy resin has increased by 1.8 % due to moisture expansion Different concrete samples were prepared for the validation of the systems. RFID sensors were embedded in different integration depths. Investigate the energy- and data transfer through concrete, also with varying moisture content. Additionally, signal strength data was used to optimize and validate the antenna characteristics in concrete. Next steps are to guarantee a sufficient energy supply for UHF RFID systems embedded in different concrete mixtures and further embedding the HF and UHF RFID systems in real bridges and buildings to validate the long term monitoring. T2 - DGZfP-Jahrestagung 2017 CY - Koblenz, Germany DA - 22.05.2017 KW - RFID sensors KW - Long-term requirements KW - Structural health monitoring KW - Passive RFID KW - Sensor requirements KW - Sensors in concrete KW - Smart structures PY - 2017 AN - OPUS4-40348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Wu, Cheng-Chieh A1 - Strangfeld, Christoph T1 - KonSens - RFID embedded² systems in concrete – validation experiments N2 - Structural Health Monitoring (SHM) is an important part of buildings surveillance and maintenance to detect material failure as early as possible and to contribute in protection of structures and their users. The implementation of Radio Frequency Identification (RFID) sensor systems without cable connection and battery into building components offers innovative possibilities to enable long-term in-situ SHM of addressed structures, bridges. The objectives of the presented study are complete embedding of RFID sensors systems in concrete, full passive communication with the systems, at best for the whole life span of structures. One challenge for this task is the highly alkaline environment in concrete, which requires non-degrading and robust encapsulation. Further Requirements are passive communication and energy supply, appropriate antenna design, placement and fixation in concrete, and the selection and implementation of sensors and connections. The concept is to develop and optimize a simple and robust system, which meets the requirements, as well as comprehensive validation in concrete specimen and real world applications. Two different systems were developed (HF and UHF RFID, respectively). First tasks were the implementation of analog sensors using the superposition principle for the signal adaption. Investigation of suitable materials for robust encapsulation and sensor protection against basic environments. Four materials were investigated in pH 13 solution for 14 days - 3D-Printer-Polymer was completely resolved - PVC has no noticeable decrease in weight - (VitaPro) glass filter for the sensor protector, has weight loss 2.7 % - The epoxy resin has increased by 1.8 % due to moisture expansion Different concrete samples were prepared for the validation of the systems. RFID sensors were embedded in different integration depths. Investigate the energy- and data transfer through concrete, also with varying moisture content. Additionally, signal strength data was used to optimize and validate the antenna characteristics in concrete. Next steps are to guarantee a sufficient energy supply for UHF RFID systems embedded in different concrete mixtures and further embedding the HF and UHF RFID systems in real bridges and buildings to validate the long term monitoring. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Passive RFID KW - RFID sensors KW - Sensors in concrete KW - Smart structures KW - Structural health monitoring PY - 2019 AN - OPUS4-48790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - KonSens - Kommunizierende Sensorsysteme für die Bauteil- und Umweltüberwachung N2 - In the KonSens Project, sensor systems are developed, validated, and operated in form of functional models for the application areas Structure Integrated Sensors and Mobile Multi-gas Sensors. Key aspects are the detection and evaluation of corrosion processes in reinforced concrete structures as well as the detection and quantification of very low concentrations of toxic gases in air. The adaption of sensor principles from the lab into real-life application including appropriate communication techniques is a major task. In recent years, Structural Health Monitoring have gained in importance, since growing age of buildings and infrastructure as well as increasing load requirements demand for reliable surveillance methods. In this regard, the project follows two strategies: First, the development and implementation of completely embedded sensor systems consisting of RFID-tag and in situ sensors, and their further application potential (e.g. for precast concrete elements, roadways, wind power plants, and maritime structures). Secondly, the development of a long-term stable, miniaturized, fiber optic sensor for a ratiometric and referenced measurement of the pH-value in concrete based on fluorescence detection as an indicator for carbonation and corrosion. Environmental pollution through emission of toxic gases becomes an increasing problem not only in agriculture (e.g. biogas plants) and industry but also in urban areas. This leads to increasing demand to monitor environmental emissions as well as ambient air and industrial air components in many scenarios and in even lower concentrations than nowadays. The selectivity of luminescence-based sensors is enabled by the combination of the sensing dye and the material, which is used as accumulation medium for concentration of the analyte. This principle allows for developing gas sensors with high selectivity and sensitivity of defined substances. Additional benefits, particularly of fluorescence-based sensors, are their capability for miniaturization and potential multiplex mode. Objective is the development and implementation of sensors based on fluorescence detection for defined toxic gases (ammonia, hydrogen sulfide, ozone, and benzene) with sensitivity in the low ppm or even ppb range. Additionally, the integration of such sensors in mobile sensor devices is addressed. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - RFID sensors KW - Sensors in concrete KW - Gas sensors KW - Mobile sensors KW - Fluorescence sensors PY - 2017 AN - OPUS4-43183 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -