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The Compressed Earth Block (CEBs) is one of the kinds of building materials which stabilized by cement. Soil is a basic component, a renewable, non-toxic and natural resource. Samples must be stabilized with a limited percentage of cement so that samples do not lose their natural properties including thermal comfort and on other hand offer high mechanical resistance. The objective of this work is to study the effect of cement content on thermal behavior of the building material of CEBs in the dry state, by studying variation of temperature with time, and measuring thermal conductivity and the specific heat, with respect to the various cement ratios added to the samples. This study is mainly an experimental and numerical, to determine how the thermal behavior evolves with the cement content in the samples CEBs. The soil was extracted from the famous city Fez in Morocco, Fez is known for its several historical monuments and buildings. After determining its granulometry and other specific characteristics, the CEBs are made by mixing soil with cement. The samples are put in plastic bags for two weeks, then removed the plastic bags from the samples and let them to dry again for an additional two weeks away from direct sun. The samples CEBs are taken cylindrical form (8 cm diameter with an average height of 12 cm). The experimental method consists of a hot ring for which a numerical modelization was developed to fit the mathematical equations of heat diffusion and the boundary conditions. For the numerical model Bouabid and Cherraj have developed numerical model which allow, with a good accuracy, to quantify the evolution of the thermal behavior of the earth material in function of cement content. Indeed, the study provides information on the influence of the cement percentage on the thermal behavior of the samples CEBs, the thermal behavior of samples increase with increase cement content.

Abstract. The stabilization of the earth material in the fields related to the earthen construction, in compliance with the standards in force, allows strong results of strength and durability. The chemical and mineralogical elements play an important role, in the presence of an 'optimum' cement dosage, to strengthen the ties between the clays and the grains of the earth.. This approach targets the search for better performances in the use of natural materials resource in an ecoresponsible habitat. This study presents the experimental results of the four techniques of mineralogical and chemical analysis on mortar specimens obtained from earth of the city of Fez. The results of the uni-axial compressive tests of the cylindrical specimens for this earth, associated by various percentages 0%, 4%, 7% and 10% by weight of cement, make it possible to analyze the effect of the mineralogical and chemical elements on the mechanical properties, namely Young's modulus, compressive strength and limiting deformation. However, we determine the water absorption coefficient of the mortar for different cement dosages in order to optimize the durability of the mortar against bad weather, rain and / or very wet climates. In the earth mortar of Fez, the strong presence of calcite (CaCO3), quartz SiO2 and dolomite CaMg (CO3)2 amplifies the improvement of the behavior of the material by the addition of cement. In fact, this strong presence of calcite stabilized the clay by cementing quartz and the cement matrix to strengthen the ties between the grains of the earth. In addition, with respect to the capillary rise, the water absorption decreases with the addition of cement. We also note that the evolution of the mechanical properties is of no importance except in the interval [4 to 7%] which represents the zone of effect for cement stabilization and which houses the optimum technicoeconomic cement dosing.Résumé. La stabilisation du matériau terre crue dans les domaines liés à la construction en terre, dans le respect des normes en vigueur, permet des résultats de résistance mécanique et de durabilité forts probants. Les éléments chimiques et minéralogiques y jouent un rôle déterminant et permettent, en présence d'un dosage 'optimal' du ciment, de renforcer les liens entre les argiles et les grains de la terre. Ainsi, la connaissance de la nature de la terre crue à utiliser dans la construction, par l'identification scientifique de ses composantes, est incontournable à cet effet. Cette démarche cible la recherche de performances meilleures dans l'utilisation des matériaux naturels et bio ressourcés au niveau d'un habitat éco responsable. Notre recherche présente les résultats expérimentaux des quatre techniques des analyses minéralogiques et chimiques sur des éprouvettes de mortier obtenues à partir d'une terre de la ville de Fès par la diffraction des rayons X, l'Infrarouge, le Microscope électronique à balayage et la fluorescence X. Les résultats des essais de compression uni-axiale des éprouvettes cylindriques de cette terre associé...

No abstract

The stabilization of the earth material in the fields related to the earthen construction, in compliance with the standards in force, allows strong results of strength and durability. The chemical and mineralogical elements play an important role, in the presence of an 'optimum' cement dosage, to strengthen the ties between the clays and the grains of the earth.. This approach targets the search for better performances in the use of natural materials resource in an eco-responsible habitat. This study presents the experimental results of the four techniques of mineralogical and chemical analysis on mortar specimens obtained from earth of the city of Fez. The results of the uni-axial compressive tests of the cylindrical specimens for this earth, associated by various percentages 0%, 4%, 7% and 10% by weight of cement, make it possible to analyze the effect of the mineralogical and chemical elements on the mechanical properties, namely Young's modulus, compressive strength and limiting deformation. However, we determine the water absorption coefficient of the mortar for different cement dosages in order to optimize the durability of the mortar against bad weather, rain and / or very wet climates. In the earth mortar of Fez, the strong presence of calcite (CaCO3), quartz SiO2 and dolomite CaMg (CO3)2 amplifies the improvement of the behavior of the material by the addition of cement. In fact, this strong presence of calcite stabilized the clay by cementing quartz and the cement matrix to strengthen the ties between the grains of the earth. In addition, with respect to the capillary rise, the water absorption decreases with the addition of cement. We also note that the evolution of the mechanical properties is of no importance except in the interval [4 to 7%] which represents the zone of effect for cement stabilization and which houses the optimum technicoeconomic cement dosing.