Publications Scientifiques
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Item Influence of superplasticizer doped by Nano-silica on the rheological and mechanical properties of cement mortars(2019) Daoui, Abdelhakim; Safi, Brahim; Zerizer, AbdellatifPrevious research indicates that the inclusion of nanosilica (NS) modifies the properties of the fresh and hardened state, compared to the traditional mineral additions. Some authors estimate that the appropriate percentage of Nano-silica should be small because of difficulties caused by agglomeration to particles during mixing, while others indicate that 10% by weight, if adjustments are made to the formulation to avoid an excess of self-drying and micro cracks that could impede strength. For this purpose, the present work aim to see the effect of the introduction mode of the nanosilica on the rheological and physic mechanical properties of cement mortars. In this study, NS was used either powdered with cement or in solution with the superplasticizer (Superplasticizer doped in nanosilicafigure (a)). Results show that the use of nanosilica powder (replacing cement on the one hand) has a negative influence on the rheological parameters and the rheological behavior of cementitious pastes. However, the introduction of nanosilica in solution in thesuperplasticizer (SP) was significantly improved the rheological parameters and the rheological behavior of cementitious pastes. Indeed, more the dosage of NS-doped SP increases more the shear stress and viscosities of the cementitious pastes become more fluid and manageable. A significant reduction of shear stress and plastic viscosity were observed that due to the increase in superplasticizer. A dosage of 1.5% NS-doped SP gave adequate fluidity and the shear rate was lower.Item Identification of elasticity modulus by vibratory analysis (Application to a natural composite : aleppo pine wood) = Identification des modules d’élasticité par analyse vibratoire (Application à un composite naturel : bois de Pin d’Alep)(EDP Sciences, 2018) Daoui, Abdelhakim; Zerizer, AbdellatifIn this paper, we present a method for the determination of the elasticity modulus in the vibratory domain of materials. This approach is based on research and interpretation of the spectrum of natural frequencies resulting from natural vibrations based on the theory of elastic beams. The tests consist of classical tests of longitudinal vibrations of natural composite beams (Aleppo pine wood), long enough to observe some natural frequencies. This identification method showed a good correlation between the theoretical and experimental values, notably the evaluation of the modal parameter for the case of the resonant frequencies and the identification of the modulus of elasticity of the materials usedItem Determination of elasticity modulus of aleppo pine wood (pinus halepensis mill) with the ultrasound method(2008) Daoui, Abdelhakim; Zerizer, Abdellatif; Marchal, RemyWith a view to determining the mechanical properties - specifically the modulus of elasticity - of fibrous composites, the nondestructive methods present certain advantages. The ultrasound technique, based on measuring the propagation velocity of an impulse and considering the elasticity coefficients of the material, enabled us to deal with the study of a well-known local species, namely Aleppo pine (Pinus halepensis Mill.), with consideration of its physical parameters such as moisture and density. The mean goal of this step is to find correlations between the acoustic behavior of the material and its physical and mechanical characteristicsItem Investigation of chemical, physical and mechanical properties of algerian date palm wood(Carl Hanser Verlag, 2014) Amirou, Siham; Zerizer, Abdellatif; Pizzi, AntonioItem Mesure des efforts de défonçage et de la qualité finale en usinant en différents angles du fil : comparaison entre le pin douglas et le pin d'Alep = Measuring cutting effort and the surface quality obtained by routing across different wood grain angles : a comparison between douglas pine and aleppo pine(2012) Aknouche, Hamid; Goli, Giacomo; Marchal, Rémy; Sandak, Jakub; Zerizer, Abdellatif; Butaud, Jean-ClaudeItem Variation de l’épaisseur du placage de déroulage des bois et son influence sur les caractéristiques mécaniques des panneaux LVL(EDP Sciences, 2014) Daoui, Abdelhakim; Descamps, Clément; Zerizer, Abdellatif; Marchal, Rémy; Pałubicki, BartoszLe LVL (Laminated Veneer Lumber) est un matériau industriel très en vogue dans la construction, c’est un matériau dérivé du bois très apprécié dans la construction en ossature bois pour la faible dispersion de ses remarquables caractéristiques mécaniques, notamment en matière des contraintes axiales, pouvant aller jusqu’au double d’un bois massif