TY - CONF A1 - Helmerich, Rosemarie A1 - Moldenhauer, Laura A1 - Voigt, Gerrit A1 - Köppe, E. T1 - Considerations for identification of moisture in building materials using Bluetooth (R) N2 - The vulnerability of low-quality concrete of some bridges to ageing and deterioration while they are exposed to environmental conditions during their service life, influence of growing population and climate changes, is a well-known effect and requires survey. For survey, the development of a low cost, cost-efficient sensor network to be embedded for continuous or attached to the surface for periodic monitoring is essential. Changing ground water conditions, flood or even leakage in fresh or disposal of waste water can lead to in-creased moisture content in building materials and structural elements as walls or floors. Moisture allows the transport of other adverse chemicals that might reduce the durability of structures. The paper presents a feasibility study about the capability of microwave modules as bluetooth® or ZigBee with frequency range at 2,4 GHz to create advanced Wireless Sensor Networks (WSN) for estimation and visualization of moisture distribution in infrastructure assets. It was found that the value of the received signal strength indication (RSSI) depends on the moisture content and can be the basis for the moisture distribution inside a massive structure. The microwave modules may be used to compose networks outside and inside of building materials or structural elements. The higher the number of connections between BLE modules, the more precise and the more distant information can be obtained from the network. Mesh networking was applied to increase the quantitative information. T2 - 9th International Conference on Bridge Maintenance, Safety and Management (IABMAS) CY - Melbourne, Australia DA - 09.07.2018 KW - Structural Health Monitoring KW - Moisture KW - Bluetooth PY - 2018 SN - 978-1-315-18939-0 SN - 978-1-138-73045-8 SP - 2752 EP - 2759 AN - OPUS4-50340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moldenhauer, Laura A1 - Helmerich, Rosemarie A1 - Köppe, E. A1 - Wittmann, J. ED - Cosmi, F. T1 - Experimental modeling approach for determining the moisture damping exponent of a Bluetooth Low Energy signal in moist building material N2 - The presented development of a damping model is a research component of an experimental feasibility study about moisture in building materials measured with Bluetooth® Low Energy (BLE) signals. This study may be part of a structural health monitoring aiming on early damage detection in the built infrastructure and is increasingly focusing on wireless sensor Network technology. It is investigated, how the Received Signal Strength Indicator (RSSI) of a BLE signal, transmitted from the BLE-module embedded in building materials with changing moisture content is damped. The BLE-module communicates with a mobile Smart Device as tablet or mobile phone via 2.45 GHz-ISMfrequency band where water dipoles start to oscillate. If the BLE-signal transfers through a moist material, the moisture Content influences the RSS-Indicator. The damping model demonstrates this damping effect on RSSI by the abstraction of the reality observed in a real system. T2 - 34th Danube Adria Symposium CY - Trieste, Italy DA - 19.09.2017 KW - Moisture damping coefficient, KW - Buliding materials KW - Bluetooth Low Energy KW - RSSI KW - Experimental approach PY - 2017 SN - 978-88-8303-863-1 U6 - https://doi.org/https://www.openstarts.units.it/handle/10077/14834 SP - 141 EP - 142 CY - Trieste, Italy AN - OPUS4-44528 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moldenhauer, Laura A1 - Helmerich, Rosemarie A1 - Köppe, E. A1 - Wittmann, H.-J. T1 - Experimental modeling approach for determining the moisture damping exponent of a bluetooth low energy signal in moist building material N2 - The presented development of a damping model is a research component of an experimental feasibility study about moisture in building materials measured with Bluetooth® Low Energy (BLE) signals. This study may be part of a structural health- and long-term monitoring aiming at early damage detection in the built infrastructure and is increasingly focusing on wireless sensor network technology. It is investigated, how the Received Signal Strength Indicator (RSSI) of a BLE signal, transmitted from the BLE-module embedded in building materials with changing moisture content is damped. The aim of the modelling is the derivation of a damping equation for the formal model to determine the moisture damping exponent to finding a correlation. T2 - 34th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - BLE Bluetooth low energy KW - Sensor network KW - RSSI Received Signal Strength Indicator KW - Structural Health Monitoring KW - Moisture measurements PY - 2018 U6 - https://doi.org/10.1016/j.matpr.2018.08.124 SN - 2214-7853 VL - 5 IS - Issue 13, Part 2 SP - 26469 EP - 26792 PB - Elsevier Ltd. CY - Radarweg 29, 1043 NX Amsterdam, The Netherlands AN - OPUS4-47171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -