Abstract
This paper describes an alternative nondestructive technique for bulk density and water content determination in soils using dual-energy computerized tomography. A first generation tomographic system (STAC-1) was used in the analysis of the specimens. The system used 137Cs (∼662 keV), 192Ir (∼316 keV) and 241Am (∼60 keV) as radiation sources and a Sodium Iodine crystal (NaI(Tl)) with photomultiplier tube as the detector. The specimens of soil tested were from different regions, one from São Paulo, and the other from Rio de Janeiro. The bulk density and the water content were determined point by point, in a transverse section of the soil specimens, using a computational algorithm that generated images of bulk density and water content. By utilizing the average pixel values of linear attenuation coefficient in these images, for each specimen, a characteristic curve could be built for each soil. The linear attenuation coefficient values agreed with the expected data. The compaction curves presented good agreement between the tomographic technique and the standard geotechnical method.
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Braz, D., Lopes, R.T. & Motta, L.M.G. Dual-energy computerized tomography in compacted soil. Geotechnical and Geological Engineering 18, 221–238 (2000). https://doi.org/10.1023/A:1026552720419
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DOI: https://doi.org/10.1023/A:1026552720419