Hydrothermal properties of compacted natural and lime-stabilized tufa: capillary absorption and thermal properties

This study presents an experimental investigation on compacted natural and stabilized tufa sourced from the Beni-Saf region (Algeria). The main objective was to investigate the influence of the hydric parameters (water content (w) and degree of saturation (S_r)) on the capillary absorption coefficient (A_w), thermal diffusivity (D), and thermal effusivity (E). In addition, particular attention was dedicated to the assessment of lime stabilization and different drying periods on the aforementioned properties. The conducted tests involved the examination of samples that were statically compacted under a vertical stress of 4 MPa at a speed rate of 1 mm/min. The results showed an inverse relationship between the capillary absorption coefficient and both the water content and the degree of saturation. Furthermore, the thermal properties (diffusivity and effusivity) displayed a linear relationship with w and S_r. A comparative analysis revealed that samples subjected to lime stabilization exhibited an increase in the coefficient A_w accompanied by a decrease in the thermal properties D and E when compared to natural tufa samples.