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International audienceWe evaluate experimentally the effect of carbonation on the hydro-mechanical properties of Portland cement. Samples were carbonated at 90 °C and 28 MPa under wet supercritical CO2. Two types of carbonation features were achieved, either the samples were homogeneously carbonated or they displayed sharp carbonation fronts. Using a tri-axial apparatus, the static elastic moduli and the mechanical strength were measured at in-situ pressure conditions (28 MPa) and showed a degradation of the mechanical properties of the samples where a carbonation front prevailed. Water and gas permeabilities were measured and showed that the samples with a carbonation front exhibit a stress sensitive permeability. P and S elastic wave velocities were measured to evaluate dynamic (ultrasonic range, 1 MHz) elastic moduli. The use of an effective medium theory approach enabled us to characterize the density and distribution of cracks within the samples. This approach outlines that the samples which developed a carbonation front were damaged

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Unfired clay building materials are recognised for their ability to regulate indoor humidity levels through their moisture buffering capacity. Research is being conducted on the moisture buffering capacity of a variety of building materials with natural materials, such as clay, and organic materials, such as hemp or straw, presenting a greater potential to regulate indoor humidity than industrial building materials. Due to their high affinity to water, which is usually regarded as detrimental, clay materials present complex hygrothermal coupling phenomena, which are still under investigation. This paper summarises some recent investigations into the dynamic water adsorption process within clay materials in relation to their ability to regulate indoor air humidity levels. First, a review of the experimental methods to characterise this behaviour is provided. A review of experimentally measured results on the material scale using compressed earth block, rammed earth or plaster samples is then provided, followed by some larger and whole building measurements.