The thermal conductivity measurement by a simplified transient hot-wire technique is applied to geomaterials in order to show\r\nthe relationships which can exist between effective thermal conductivity, texture, and moisture of the materials. After a validation\r\nof the used ââ?¬Å?one hot-wireââ?¬Â technique in water, toluene, and glass-bead assemblages, the investigations were performed (1) in glassbead\r\nassemblages of different diameters in dried, water, and acetone-saturated states in order to observe the role of grain sizes and\r\nsaturation on the effective thermal conductivity, (2) in a compacted earth brick at different moisture states, and (3) in a limehemp\r\nconcrete during 110 days following its manufacture. The lime-hemp concrete allows the measurements during the setting,\r\ndesiccation and carbonation steps. The recorded ?T/ ln(t) diagrams allow the calculation of one effective thermal conductivity\r\nin the continuous and homogeneous fluids and two effective thermal conductivities in the heterogeneous solids. The first one\r\nmeasured in the short time acquisitions (<1 s) mainly depends on the contact between the wire and grains and thus microtexture\r\nand hydrated state of the material. The second one, measured for longer time acquisitions, characterizes the mean effective thermal\r\nconductivity of the material.
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