TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Kammermeier, Michael A1 - Müller, Maximilian A1 - Strangfeld, Christoph T1 - RFID sensor systems embedded in concrete – systematical investigation of the transmission characteristics T2 - 8th European Workshop On Structural Health Monitoring N2 - Long-term completely embedded sensor systems offer innovative possibilities for structural health monitoring of concrete structures. Measuring of relevant parameters, e.g., temperature, humidity, or indication of corrosion can be performed with low energy sensors. This allows to implement passive RFID sensor systems without cable connection and battery, which are power supplied exclusively by the electromagnetic field from the external reader device. To evaluate characteristics and conditions of this concept, a systematical investigation of the transmission characteristics with variation of relevant parameters, as communication frequency, installation depth, type of concrete, moisture content, etc. is currently carried out in an interdisciplinary research project at BAM. First results are presented in this paper. T2 - 8th European Workshop On Structural Health Monitoring CY - Bilbao, Spain DA - 05.07.2016 KW - Structural health monitoring KW - Embedded sensor KW - Energy harvesting KW - Wireless sensors KW - RFID sensors KW - Transmission characteristics PY - 2016 SP - 1 EP - 5 AN - OPUS4-37129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Kammermeier, Michael A1 - Müller, Maximilian A1 - Strangfeld, Christoph T1 - Transmission characteristics of RFID sensor systems embedded in concrete T2 - Proceedings of the IEEE Sensors 2016 N2 - Completely embedded sensor systems for long-term operation offer innovative possibilities for structural health monitoring of concrete structures. Measuring of relevant parameters, e.g., temperature, humidity, or indication of corrosion can be performed with low energy sensors. This allows to implement passive RFID sensor systems without cable connection and battery, which are power supplied exclusively by the electromagnetic field from the external reader device. To evaluate characteristics and conditions of this concept, a systematical investigation of the transmission characteristics with variation of relevant parameters, as communication frequency, installation depth, type of concrete, moisture content, etc. is currently carried out in an interdisciplinary research project at BAM. First results are presented in this paper. T2 - IEEE Sensors 2016 CY - Orlando, FL, USA DA - 30.10.2016 KW - Embedded sensors KW - Energy harvesting KW - Wireless sensors KW - RFID sensors KW - Transmission characteristics KW - Structural health monitoring PY - 2016 SN - 978-1-4799-8287-5 SN - 1930-0395 SP - 1541 EP - 1543 PB - IEEE AN - OPUS4-38388 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Strangfeld, Christoph ED - Chan, T. ED - Mahini, S, T1 - Embedded wireless sensor systems for long-term SHM and corrosion detection in concrete components T2 - 8th International Conference on Structural Health Monitoring of Intelligent Infrastructure - Proceedings N2 - State-of-the-art communication standards like RFID and Bluetooth Low Energy enable the development of sensor systems which can be completely embedded into concrete components for long-term SHM and early damage detection. Objective of the project KonSens which is carried out at BAM is the development, implementation, and validation of sensors for measuring of Parameters relevant for corrosion, like moisture, pH value, and electrical conductivity, inside steel reinforced concrete components. The primarily addressed application is detection and evaluation of corrosion processes in concrete bridges. In contrast to cable connected sensors, embedded wireless sensors avoid any pathways for intrusion of moisture and chemicals, e.g., chlorides which could trigger corrosion activity. To allow for long-term, ideally life-time operation, the once embedded sensor systems must work highly energy efficient. One option are passive RFID sensor systems, which work without battery. The energy is transmitted to the system through the electromagnetic field, even to operate sensors. A crucial parameter is the transmission depth in concrete. First experiments with RFID sensors working at frequencies of 13.56 MHz (HF) and 868 MHz (UHF) embedded in concrete specimen resulted positive for transmission depths of up to 13 cm, which is quite promising, considering that corrosion would appear first at the top level of rebars. A second generation of passive RFID sensor systems has been implemented with improved antenna design. Current experiments using these systems focus on the Transmission characteristics in terms of transmission depths and the impact of concrete moisture. Low-energy humidity sensors are used and analysed regarding their capability for measuring the material moisture. Additionally, a relation between transmitted power to the embedded sensor and the moisture content of the concrete specimen caused by energy absorption can be presumed and is under systematic investigation. T2 - International Conference on Structural Health Monitoring of Intelligent Infrastructure 2017 CY - Brisbane, Australia DA - 05.12.2017 KW - RFID sensors KW - Structural health monitoring KW - Sensors in concrete KW - Smart structures PY - 2017 SN - 978-1-925553-05-5 SP - 1 EP - 7 AN - OPUS4-43492 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Bartholmai, Matthias ED - Cosmi, Francesca T1 - RFID sensor system embedded in concrete –validation of UHF antenna geometries in different concrete depths T2 - 34rd Danubia - Adria Symposium on Advances in Experimental Mechanics - Book of proceedings N2 - This paper is a further research on the topic of the complete embedding of radio frequency identification (RFID) sensors in concrete. The focus is on the antenna of the transponder. Earlier investigations of different RFID technologies, embedded in concrete, showed a difference in energy transmission. The transmission through concrete at ultra high frequency (UHF), in spite of the large signal range, does not match the targeted application specific task. Therefore, the antenna characteristics have been examined more closely. The antenna is an important component for the application of RFID. Through the antenna, energy and data transfer takes place, so it is important to design an optimal antenna to accomplish a maximum embedding depths in concrete. To identify the optimal antenna geometry, different UHF antenna types were selected and investigated. An experimental comparison was performed to gain more information about the damping behavior and antenna characteristics in concrete. T2 - 34th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - RFID sensors KW - Structural health monitoring KW - Passive RFID KW - UHF antenna KW - Sensors in concrete KW - Smart structures PY - 2017 SN - 978-88-8303-863-1 SP - 114 EP - 115 CY - Trieste AN - OPUS4-42093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Chahardehinejad, Omid A1 - Bartholmai, Matthias ED - Pastrama, S. D. ED - Constantinescu, D. M. T1 - Passive RFID Transponder – Low-Power Multi-Sensor Interface for Structural Health Monitoring in Concrete T2 - 35th Danubia - Adria Symposium on Advances in Experimental Mechanics: extendet abstracts N2 - Structural Health Monitoring (SHM) has become very important in today's rapidly developing time. High buildings, large bridges and complex technical structures need to be monitored continuously and this over long periods. Visual monitoring cannot evaluate the internal condition of building structures. Thus, material embedded sensors are needed. Cable connection of these sensors pose the disadvantage of weak spots and water intrusion. For concrete embedded sensors the use of batteries is not convenient, because of limited lifetime, difficult charging, and generation of electrical waste.. Hence, monitoring should be implemented preferentially with firmly embedded passive RFID sensor modules. However, since the concrete structure forms an electromagnetically reflective and absorbing barrier, only limited energy can be transmitted to the module. This project requires a highly energy-saving system, which can record different sensor parameters at critical points. T2 - 35th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Sinaia, Romania DA - 25.09.2018 KW - RFID KW - Structural Health Monitoring KW - Passive sensor interface KW - Concrete PY - 2018 SN - 978-606-23-0874-2 SP - 141 EP - 142 AN - OPUS4-46097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Müller, Maximilian A1 - Bartholmai, Matthias ED - Aulova, Alexandra ED - Rogelj Ritonja, Alenka ED - Emri, Igor T1 - RFID sensor systems embedded in concrete - requirements for long-term operation T2 - 33rd Danubia - Adria Symposium on Advances in Experimental Mechanics - Book of abstracts N2 - One of the more difficult tasks for structural health monitoring is the continuous evaluation of the stability and load capacity of the building materials. This knowledge can be won, e.g., by taking material samples at the examining place with the drawback of partly destroying the structure. To avoid this, modern sensor and communication technologies offer promising methods for non-destructive testing. To address the tasks for monitoring of concrete structures, in the presented study, different sensors were combined with RFID transponders and embedded in concrete components. T2 - 33rd Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - Structure health monitoring KW - Concrete KW - Embedded KW - RFID sensors PY - 2016 SN - 978-961-94081-0-0 SP - 68 EP - 69 CY - Ljubljana AN - OPUS4-37535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Zimmek, David A1 - Bartholmai, Matthias ED - Helmerich, Rosemarie ED - Ilki, A. ED - Motavalli, M. T1 - Smart electronic helper for long-term monitoring of bridges and building structures T2 - Proceedings of the 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) N2 - Increasing traffic volume on the one hand and ageing infrastructure on the other hand have created many new challenges for maintenance and structural health monitoring of roads and bridges. In the past, many bridges and road structures have been neglected, often resulting in traffic congestion, road closure, and increased repair costs. This research is concerned with the development of a system to improve the challenge of maintenance and early detection of damage, particularly moisture penetration and corrosion of steel reinforced concrete components. The objective is to develop a method that will also work after 30 years and longer. Many new IoT solutions are equipped with internal energy storage elements (accumulators or batteries) which are inappropriate here, since most relevant signs of concrete degradation occur after decades, where the functioning of such elements are more than questionable. The presented technology approach uses radio-frequency identification (RFID) and enables connectivity to sensors. It offers the advantage of an passive, completely independent energy supply without any energy storage components. Since the system should be permanently embedded in concrete, it is crucial to develop a long-term stable device which is adapted to the environmental influences of the structure, e.g., long-term resistance in very alkaline environment of pH 13. In numerous experiments, the robustness of the system was tested and evaluated. Various tests with encapsulations to protect the electronics were performed, and for long-term validation different concrete specimens were instrumented with RFID-sensor-systems. Their operating time is now around two years and investigations for signs of fatigue and damage to the encapsulation and the electronics are ongoing. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Long term monitoring KW - Passive RFID KW - SHM KW - Sensors KW - Smart structures PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489890 SP - 1 EP - 6 PB - German Society for Non-Destructive Testing (DGZfP e.V.) AN - OPUS4-48989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Grotelüschen, Bjarne A1 - Bartholmai, Matthias A1 - Strangfeld, Christoph ED - Kossa, A. ED - Kiss, R. T1 - Towards Autonomous NDT Inspection: Setup and Validation of an Indoor Localization System T2 - 39th Danubia-Adria Symposium on Advances in Experimental Mechanics - Book of Abstracts N2 - Monitoring and maintenance of civil infrastructure are of great importance, as any undetected damage can cause high repair costs, unintended deadtime, or endanger structural integrity. The inspection of large concrete structures such as bridges and parking lots is particularly challenging and time-consuming. Traditional methods are mostly manual and involve mapping a grid of measurement lines to record the position of each measurement. Current semi-automated methods, on the other hand, use GPS or tachymeters for localization but still require trained personnel to operate. An entirely automated approach using mobile robots would be more cost- and time-efficient. While there have been developments in using GPS-enabled mobile robots for bridge inspection, the weak signal strength in indoor areas poses a challenge for the automated inspection of structures such as parking lots. This paper aims to develop a solution for the automated inspection of large indoor concrete structures by addressing the problem of robot localization in indoor spaces and the automated measurement of concrete cover and rebar detection. T2 - 39th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Siófok, Hungary DA - 26.09.2023 KW - NDT Inspection KW - Mobile Robot KW - Indoor Localization KW - Setup and Validation PY - 2023 SN - 978-963-421-927-9 SP - 88 EP - 89 PB - Hungarian Scientific Society of Mechanical Engineering (GTE) CY - Siófok, Hungary AN - OPUS4-58660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Johann, Sergej A1 - Müller, Maximilian A1 - Bartholmai, Matthias T1 - Moisture Measurements with RFID based Sensors in Screed and Concrete T2 - 8th European Workshop On Structural Health Monitoring N2 - To quantify the moisture in concrete, RFID based humidity sensors are embedded. Passive high frequency, ultra-high frequency RFID tags as well as active Bluetooth sensors are tested. After concreting, all sensors measure the corresponding relative humidity to monitor the concrete moisture. Two case studies are performed, embedding in an existing construction, i.e. the duraBASt test bridge, and embedding in cement based mortar in the laboratory. As basis for robust and long-life sensors in alkaline concrete, different casing materials are tested. Furthermore, signal strength measurements and their sensitivity to different moisture levels are performed. T2 - 8th European Workshop On Structural Health Monitoring CY - Bilbao, Spain DA - 05.07.2016 KW - Humidity sensors KW - Moisture measurements KW - RFID based sensors KW - DuraBASt PY - 2016 SP - 1 EP - 10 AN - OPUS4-36817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Johann, Sergej A1 - Müller, Maximilian A1 - Bartholmai, Matthias T1 - Embedded passive RFID-based sensors for moisture monitoring in concrete T2 - Proceedings of the IEEE Sensors 2017 N2 - Damages in infrastructure due to moisture amount to billions of Euros every year. For a more predictive structural health monitoring in civil engineering, the detection and monitoring of hazardous moisture in steel reinforced concrete constructions is of high interest. The sensors have to be wireless, elsewise they weaken the concrete cover of the rebars. The lifetime of such constructions is normally decades, thus the sensors have to be battery-free and fully passive. Considering these requirements, passive RFID-based sensors are developed. Communication and energy supply are realized wireless via the electromagnetic field of a RFID transmitter. The passive RFIDbased sensors are embedded into the concrete to enable the monitoring of moisture transport in porous materials. Results of the hydration process are shown. T2 - IEEE Sensors 2017 CY - Glasgow, Scotland, UK DA - 30.10.2017 KW - Embedded sensors KW - Wireless sensors KW - Passive sensors KW - RFID-based sensors KW - Structural health monitoring KW - Moisture PY - 2017 SN - 978-1-5386-4056-2 DO - https://doi.org/10.1109/ICSENS.2017.8234166 SP - 870 EP - 872 PB - IEEE AN - OPUS4-43033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -