{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T19:10:36Z","timestamp":1780600236861,"version":"3.54.1"},"reference-count":46,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,19]],"date-time":"2022-08-19T00:00:00Z","timestamp":1660867200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Grant Agency of the Czech Republic","award":["GA\u010cR Grant No. 20-28853Y"],"award-info":[{"award-number":["GA\u010cR Grant No. 20-28853Y"]}]},{"name":"Grant Agency of the Czech Republic","award":["GAUK; Project No. 337121"],"award-info":[{"award-number":["GAUK; Project No. 337121"]}]},{"name":"Grant Agency of the Czech Republic","award":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"],"award-info":[{"award-number":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"]}]},{"name":"Charles University Grant Agency","award":["GA\u010cR Grant No. 20-28853Y"],"award-info":[{"award-number":["GA\u010cR Grant No. 20-28853Y"]}]},{"name":"Charles University Grant Agency","award":["GAUK; Project No. 337121"],"award-info":[{"award-number":["GAUK; Project No. 337121"]}]},{"name":"Charles University Grant Agency","award":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"],"award-info":[{"award-number":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"]}]},{"name":"Charles University","award":["GA\u010cR Grant No. 20-28853Y"],"award-info":[{"award-number":["GA\u010cR Grant No. 20-28853Y"]}]},{"name":"Charles University","award":["GAUK; Project No. 337121"],"award-info":[{"award-number":["GAUK; Project No. 337121"]}]},{"name":"Charles University","award":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"],"award-info":[{"award-number":["MSCA-IF IV; Project No. CZ.02.2.69\/0.0\/0.0\/20_079\/0017987"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Knowledge of physical and mechanical properties of geomaterials is fundamental to characterise their response to external forcings (mechanical, climatic) at various scales. This is true, for instance, in slope stability assessments, civil engineering works, and agriculture. The direct evaluation of these properties in situ can be difficult, especially in inaccessible or vast areas, and so can be the sampling and subsequent testing in the laboratory\u2014where ensuring the representativeness of the acquired data at the scale of analysis poses an additional challenge. Thus, empirical correlations with more readily determinable quantities remain a powerful and practical tool. Recently, several sensors, able to inform on various geomaterial properties, have been developed. However, applications have typically targeted rocks, while studies on uncemented geomaterials (soils, geotechnically speaking) are lacking. Here, we propose a simple method to evaluate the porosity and critical state friction angle of soils via infrared thermography, consisting of periodic acquisitions of images in infrared wavelengths. To demonstrate the method\u2019s capability, we analysed the cooling behaviour of samples of bentonite, kaolin, and sand (for which an extensive characterisation exists in the literature), after compaction to different porosities and pre-heating in an oven. We interpreted the results by seeking the optimal time interval for which a cooling rate index (CRI) could be defined, which is best linked with the target property. We found that the CRI correlates very well with the critical state friction angle (R2 &gt; 0.85) and that different materials show unique and strong (R2 = 0.86\u20130.99) relationships between their porosity and the CRI, which also varies in a material-specific fashion according to the explored time interval. Although a systematic investigation on a wide range of natural soils is warranted, we argue that our method can be highly informative and could be used to calibrate remote sensing-based full-scale implementations in situ for various purposes.<\/jats:p>","DOI":"10.3390\/rs14164067","type":"journal-article","created":{"date-parts":[[2022,8,22]],"date-time":"2022-08-22T01:56:40Z","timestamp":1661133400000},"page":"4067","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Investigating the Potential of Infrared Thermography to Inform on Physical and Mechanical Properties of Soils for Geotechnical Engineering"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0756-2175","authenticated-orcid":false,"given":"Marco","family":"Loche","sequence":"first","affiliation":[{"name":"Institute of Hydrogeology, Engineering Geology and Applied Geophysics, Charles University, Albertov 6, 128 43 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3505-7456","authenticated-orcid":false,"given":"Gianvito","family":"Scaringi","sequence":"additional","affiliation":[{"name":"Institute of Hydrogeology, Engineering Geology and Applied Geophysics, Charles University, Albertov 6, 128 43 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9969-4641","authenticated-orcid":false,"given":"Jan","family":"Blah\u016ft","sequence":"additional","affiliation":[{"name":"Institute of Rock Structure & Mechanics, Czech Academy of Sciences, V Hole\u0161ovi\u010dk\u00e1ch 41, 182 09 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filip","family":"Hartvich","sequence":"additional","affiliation":[{"name":"Institute of Rock Structure & Mechanics, Czech Academy of Sciences, V Hole\u0161ovi\u010dk\u00e1ch 41, 182 09 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1007\/s10346-019-01306-4","article-title":"Revisiting Strength Concepts and Correlations with Soil Index Properties: Insights from the Dobkovi\u010dky Landslide in Czech Republic","volume":"17","author":"Scaringi","year":"2020","journal-title":"Landslides"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"635","DOI":"10.1002\/wat2.1097","article-title":"Emerging Methods for Noninvasive Sensing of Soil Moisture Dynamics from Field to Catchment Scale: A Review","volume":"2","author":"Bogena","year":"2015","journal-title":"WIREs Water"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.envdev.2018.12.007","article-title":"Modeling Soil Salinity Using Direct and Indirect Measurement Techniques: A Comparative Analysis","volume":"29","author":"Abdullah","year":"2019","journal-title":"Environ. Dev."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Loche, M., Scaringi, G., Blah\u016ft, J., Melis, M.T., Funedda, A., Da Pelo, S., Erb\u00ec, I., Deiana, G., Meloni, M.A., and Cocco, F. (2021). An Infrared Thermography Approach to Evaluate the Strength of a Rock Cliff. Remote Sens., 13.","DOI":"10.3390\/rs13071265"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"108108","DOI":"10.1016\/j.geomorph.2022.108108","article-title":"A Thermo-Hydro-Mechanical Approach to Soil Slope Stability under Climate Change","volume":"401","author":"Scaringi","year":"2022","journal-title":"Geomorphology"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Mineo, S., Cali\u00f2, D., and Pappalardo, G. (2022). UAV-Based Photogrammetry and Infrared Thermography Applied to Rock Mass Survey for Geomechanical Purposes. 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