{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,19]],"date-time":"2026-07-19T03:48:44Z","timestamp":1784432924470,"version":"3.55.0"},"reference-count":59,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,10]],"date-time":"2023-05-10T00:00:00Z","timestamp":1683676800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Federal Ministry for Housing, Urban Development and Building (BMWSB)","award":["SWD-10.08.18.7-20.49"],"award-info":[{"award-number":["SWD-10.08.18.7-20.49"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>For the investigation of moisture and salt content in historic masonry, destructive drilling samples followed by a gravimetric investigation is still the preferred method. In order to prevent the destructive intrusion into the building substance and to enable a large-area measurement, a nondestructive and easy-to-use measuring principle is needed. Previous systems for moisture measurement usually fail due to a strong dependence on contained salts. In this work, a ground penetrating radar (GPR) system was used to determine the frequency-dependent complex permittivity in the range between 1 and 3 GHz on salt-loaded samples of historical building materials. By choosing this frequency range, it was possible to determine the moisture in the samples independently of the salt content. In addition, it was possible to make a quantitative statement about the salt level. The applied method demonstrates that with ground penetrating radar measurements in the frequency range selected here, a salt-independent moisture determination can be carried out.<\/jats:p>","DOI":"10.3390\/s23104616","type":"journal-article","created":{"date-parts":[[2023,5,10]],"date-time":"2023-05-10T04:26:29Z","timestamp":1683692789000},"page":"4616","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Quantification of Humidity and Salt Detection in Historical Building Materials via Broadband Radar Measurement"],"prefix":"10.3390","volume":"23","author":[{"given":"Oliver","family":"Blaschke","sequence":"first","affiliation":[{"name":"Institute of Sensor and Actuator Technology, Coburg University of Applied Sciences and Arts, Am Hofbr\u00e4uhaus 1b, 96450 Coburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Felix","family":"Brand","sequence":"additional","affiliation":[{"name":"Institute of Sensor and Actuator Technology, Coburg University of Applied Sciences and Arts, Am Hofbr\u00e4uhaus 1b, 96450 Coburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8829-1161","authenticated-orcid":false,"given":"Klaus Stefan","family":"Drese","sequence":"additional","affiliation":[{"name":"Institute of Sensor and Actuator Technology, Coburg University of Applied Sciences and Arts, Am Hofbr\u00e4uhaus 1b, 96450 Coburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"426","DOI":"10.1002\/bate.200590148","article-title":"Probleme und L\u00f6sungen beim Feuchtigkeitsschutz des Mauerwerks von Baudenkm\u00e4lern am Beispiel zweier gro\u00dfer Barockbauten in Wroc\u0142aw","volume":"82","author":"Adamowski","year":"2005","journal-title":"Bautechnik"},{"key":"ref_2","unstructured":"(2023, March 15). 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