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This work presents the results of a multidisciplinary study on the characterization of the composition of certain joint mortars from the ancient city of Hippo (Algeria), one of the most important North African cities in antiquity. Twenty mortar samples were analysed by X-Ray Fluorescence (XRF), powder X-ray diffraction (XRPD), optical microscopy (OM), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS) and thermogravimetric analysis (TGA). Their main physical properties, like solid and dry density and porosity, have been measured by geotechnical procedures. The typological observation by OM showed the existence of four types of sand used as aggregates that ranged from fine to coarse and were mixed with a white to russet natural lime binder. These mortars consisted mainly of mixtures of calcite and rock fragments, and sometimes pieces of red tile. It was recognized that the origins of the natural granules were sands produced by marine erosion of the Edough Mountains. The analysis by XRPD and TGA indicates that the mortars consisted of a mixture of lime/aggregates of low to medium hydraulicity. The analysis of the main chemical components by XRF allowed for the confirmation of the dating of certain monuments and suggested a new dating for other monuments.

This work is intended for the development of a numerical method to simulate flows and solute transport in multiphasical porous medium taking into consideration the interaction of solid/solute. More precisely, the studied problem is modeled by a coupled system composed of an elliptical equation (for the flow) and an equation convection-diffusion-reaction (for the transfer). Numerical simulations were realistic for two-dimensional problems confirming the stability and efficiency of the combined scheme in the characterization of a pollutant transport through an unsaturated zone of an industrial site.

This work presents the results of a multidisciplinary study on the characterization of the composition of certain joint mortars from the ancient city of Hippo (Algeria), one of the most important North African cities in antiquity. Twenty mortar samples were analysed by micro-chemical analysis, including powder X-ray diffraction (XRPD), optical microscopy (OM), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA). Their main physical properties, like solid and dry density, porosity. have been measured by geotechnical procedures. The typological observation by OM showed the existence of four types of sand used as aggregates that ranged from fine to coarse and were mixed with a white to russet natural lime binder. This mortars consisted mainly of mixtures of calcite and rock fragments and sometimes pieces of red tile. It was recognized that the origins of the natural granules were sands produced by marine erosion of the Edough Mountains. The analysis by XRF, XRPD and TGA indicates that the mortars consisted of a mixture of lime/aggregates of low to medium hydraulicity. The analysis of the main chemical components by XRF allowed for the confirmation of the dating of certain monuments and suggested a new dating for other monuments.

In chemo-mechanical coupling of clays, chemical phenomena are likely to have a stronger influence on the mechanical behaviour and mechanical actions can modify the chemical behaviour. The understanding of these different phenomena, taking into account the coupled mechanisms, is essential in the context of the problem of the durability of structures and works built on polluted sites. Thus, the laboratory characterisation of the chemo-mechanical behaviour of a clay contaminated by light hydrocarbon pollutant (BTEX: benzene) was carried out. First in the absence of pollutants, i.e., by the presence of water only, then under the influence of the pollutant, all in two stages: with no external stress, then under imposed external stress. This study presents an experimental protocol based on a series of uniaxial consolidation tests, specific oedometric tests and direct shear strength, this tests performed under controlled saturation conditions and in the presence of organic contamination by benzene. All results confirm the influence of pollutants in different concentrations on the mechanical behaviour of the soil. They show a strong increase in compressibility and a significant increase in swelling, the soil becomes more cohesive, low friction and less elastic. Furthermore, the results show that external load forces play a major role in modifying the behaviour of clay.