Powder bentonite was analyzed by different experimental techniques. The data from SEM (Scanning electron microscope), XRD (X-ray diffraction), and XRF (X-ray fluorescence) show that bentonite is Na-type, with montmorillonite as the dominant phase. The geotechnical study shows a very plastic silty (IP = 445% > 50%) material. The methylene blue value (MBV) is determined to be 0.40 indicating that our bentonite is classified as a sandy silty clay, sensitive to water and not very calcareous. The needed data for the calculations of the dynamic thermal characteristics of compacted bentonite are the thickness of the material, bulk density, thermal conductivity, massic heat capacity, and the period of thermal variations. The thermal conductivity (from 0.3275 W/m.K to 0.4456 W/m.K) as the bulk density (from 2.074 g/cm³ to 2.292 g/cm³) of pure bentonite increases with the increase of the compaction intensity (from 10 to 50 bar). The period is one day (86400 s), corresponding to the daily climatic variations. The calculations were made using a flow chart and taking into account the exterior and interior superficial thermal resistances. To improve the thermal and mechanical strength of bentonite, three compositions of sand, cement and lime based on bentonite were used. The composition B₁₅S₈₀C₅ with 15% bentonite, 5% cement and 80% sand is the most suitable for eventual use in the building sector since it has a lower damping coefficient and a higher internal capacity.

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