Browsing by Author "Benmounah, A."

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The application of the graph theory to improve the algerian refineries availability
(2010) Benmounah, A.; Hachemi, T.; Mebarkija, Dj.
Behavior of mortars hydraulic and organic matrix in aggressive environments
(2013) Saidi, Mohammed; Safi, Brahim; Samar, Mohamed Faouzi; Benmounah, A.; Hamiane, Messaoud
Caractérisation d’une préparation semi-solide traditionnelle antibrûlure = Characterization of anti-scald traditional semisolid preparation
(Springer, 2014) Hamadi, F.; Boudif, K.; Gougam, H.; Djouab, A.; Allane, T.; Benmounah, A.; Benamara, S.
Caractérisation rhéologique des fluides de forage à base d’eau, en présence d’un inhibiteur de gonflement
(2010) Safi, Brahim; Benmounah, A.; Gueciouer, Abderazak; Samar, Mohamed Faouzi
L’objectif de ce travail sera la mise au point de formulations de fluides de forage à base d’eau, optimisées avec l’ajout d’un inhibiteur de gonflement, destiné pour le forage de la phase 8" 3/8. Pour ce, nous avons d’abord élaboré différents systèmes à base de chlorure de potassium (KCl) et de polymère (PHPA) qui diminueront le gonflement des argiles tout en respectant les exigences environnementales. Ensuite, nous avons étudié le comportement rhéologique (viscosité plastique et yield-value) de chaque élément de la formulation en les soumettant aux effets de la température, de la salinité et de l’alcalinité, avant d’aboutir enfin à la formulation finale qui sera soumise ensuite à des tests standards, selon les normes API. Les résultats obtenus montrent une diminution significative du gonflement et la formulation retenue présente des caractéristiques physico-chimiques satisfaisantes ainsi qu’un comportement rhéologique rhéofluidifiant proche du modèle de Hershel Bulkley
A comparative study of the creep behavior of laminated composites : effect of type of fiber and matrix
(Academic Journals, 2017) Basaid, D.; Aribi, C.; Kari, J.; Benmounah, A.; Safi, Brahim
This paper presents the effect of matrix type on creep behavior at 80% loads of ultimate tensile strength of two laminated composites at different fiber and matrix system. For this, two types of laminated composites were manufactured based on two types of fibers (carbon fabric and glass fabric) with different matrix systems EPOCAST 50-A1 (EP50-A), Epoxy STR (STR) and Epoxy INJ812 (INJ). The tensile and creep behavior of each laminated composite was studied in the same test conditions. A microstructural study was also investigated by SEM-microscopy on the morphology of composite specimens after creep rupture failures at 80% of applied load. The obtained results showed clearly the influence of matrix type used on the tensile and creep behavior of studied composites. Indeed, it was noted that no creep rupture failures were observed in short-term (less than 4 h) for INJ/Carbon composite at tensile creep tests at 80% loads of ultimate tensile strength. At the same ultimate tensile strength, EP50/Carbon composite showed a best creep behavior up to 30 h and had a creep modulus higher than other laminated composites. The observation of rupture facets of all composite samples showed clearly that the rupture will take place in the direction of loading, creating voids at the interface resin/fiber. These are observed based on the nature of the matrix used
Comportement rhéologique et physico-mécanique des ciments composés (CEMII/A) en présence d'un nouvel adjuvant superplastifiant (AETERNUM-1) dans les milieux agressifs
(2012) Benmounah, A.; Kheribet, Rabia; Safi, Brahim; Saidi, Mohammed
Comportement rhéologiques des pâtes cimentaires pour bétons autoplaçants
(2009) Benmounah, A.; Samar, M.; Kherib, R.; Said, M.
L’utilisation des adjuvants dans la formulation des bétons autoplaçants tend à se généraliser. Cependant, il est nécessaire de tenir compte de la composition chimique du ciment, particulièrement de la teneur en SO3, qui peut inhiber ou limiter l’action de ces superplastifiants. Afin de mettre en évidence ces phénomènes, on se propose d’évaluer l’action des sulfates en incorporant des ajouts sulfatés de nature différente. Notre travail consiste donc à étudier les propriétés rhéologiques et les caractéristiques physiques des pâtes obtenues à base de deux types de ciment (CPA et CRS). L’expérimentation porte sur deux rapports E/C (0.50 et 0.30). Pour le second, nous avons utilisé un superplastifiant de type Polynaphtalène Sulfonate (PNS). Les résultats obtenus montrent en effet que la présence des sulfates entraîne des comportements rhéologiques différents en fonction de la nature des sulfates et des ciments utilisés
Contribution to the design of a Parabolic trough collector with composite material using GRP pipes scrap
(2017) Baali, Brahim; Benmounah, A.; Kari, D.; Mohammedi, K.
The world revolution is moving towards a low-carbon and sustainable development. When environmental costs and considerations of security of supply are included, renewable energy becomes the alternative to be considered. Among renewable energies, Parabolic Trough Collector power plants constitute the biggest share of the installed concentrating solar power technology. The bearing structure is the most expensive part of a parabolic trough power plant. It has the function to carry the mirrors in the right position, to give stability to the troughs and to allow an exact Sun tracking. To fulfill these functions, structures must meet certain requirements. In particular, the stiffness requirements are very high. It’s obvious that an inappropriate carrier structure should involve additional material and manufacturing costs. Composite materials have great potential to be suited for development of renewable energy structures. It refers to any structure with two or more distinct materials that are combined to create an engineered product with properties greater than the sum of its parts. Glass reinforced polyester (GRP) with E-glass as the reinforcing fiber is the most common form of composite construction. GRP pipes scraps derived from cutting process can be revalorized and used in the bearing structure of a parabolic trough. The advantage of these materials lies in their high mechanical strength, corrosion resistance and low density compared to metals. Additionally, their high stiffness allows longer troughs so that the number of pylons and tracking units can be reduced, which reduces costs. The stiffness of GRP pipes combined with lightweight structure allows the use of weaker foundations and monitoring mechanisms. A lightweight structure is also less susceptible to deformations generated by its own weight. In addition, light structures reduce the energy demand for collector tracking.
Correlation between v-funnel and mini-slump test results with viscosity
(Springer, 2013) Bouziani, T.; Benmounah, A.
Self-Compacting Mortars (SCM) can be regarded as high flowing mortars, which must show both a good fluidity (to fill complex formwork shapes) and sufficient viscosity (to avoid segregation). The characterization and control of fresh properties are proving to be critical for the success of SCM design. Usually, this task is performed through technological tests such as v-funnel and minislump. However, the use of viscometers can successfully perform better access of fresh properties. The objective of the present work is to correlate experimental results of v-funnel and mini-slump tests with viscosity of SCM, measured at different rotational speeds, and with constants a and b calculated from the power-law viscosity model. Linear relationships between both v-funnel and minislump tests and viscosity were demonstrated. Statistical models are also established to highlight the influence of constants a and b on the v-funnel and mini-slump variations. Results indicate the usefulness of established models to better understand the trade-off between constants a and b on fresh properties measured by v-funnel and mini-slump tests
Development and structural study of cements containing additions of industrial waste
(2010) Saidi, M.; Hamiane, M.; Safi, Brahim; Benmounah, A.
Certain mineral additions exploit a very significant role the behavior and the ageing of the works in the corrosive conditions and one can use them like barriers against the aggressiveness and the phenomenon of corrosion of the concretes. Cements made up of additions can be recommended especially in massive works, the stoppings, maritime and underground constructions and in the cementing of the oil wells. The use of the adequate additions ensures the long-term stability and durability of the concretes of the underground, maritime works and the cementing of the oil wells… etc. To this end, within the framework of valorization of these additions (active and inert), in this study we were interested only in the study of the influence of incorporation of limestone, pozzolana, slag, tuff and dust electrostatic precipitator (crushed finely) like active addition in the matric E of cement, its effect on the behavior and ageing of cement S made up and on the microstructure of the concrete by a structural characterization by XRD
Development of an Antireflection Layer Using a LDS Based on β-SiC Nanoparticles
(Springer, 2020) Benfadel, K.; Kaci, S.; Hamidouche, F.; Keffous, A.; Benmounah, A.; Manseri, A.; Achacha, S.
The main objective of this work is to use β-SiC (also called 3C-SiC) silicon carbide nanoparticles to formulate composite layer for wavelength conversion. Silicon Carbide nanopowders (npβ-SiC) were successfully synthesized by sol-gel method and followed by carbothermal reduction. Composite thin layers based on np-β-SiC incorporated into polyvinyl alcohol, (PVA) as matrix, where prepared. We have investigated the composite layers deposited silicon solar cell as a luminescent down shifting layer (LDS) to convert UV wavelengths. The texturation of the substrates by making pyramids, pyramids with nanowires was investigated in order to decrease the surface reflectance of silicon surface. An improvement in the spectral response of the obtained solar cells was very remarkable. In order to confirm this property, electro-optical characterizations were carried out on the solar cell with the developed composite layer and also on that without β-SiC/PVA coating, as reference. The morphological quality of the used substrates was examined by SEM images. EQE measurements have shown a noticeable increase showing the ability to use the prepared composite layer as lightweight encapsulation material for photovoltaic devices
Effect of alkalinity and the nature of the basic solution [Ca(OH)2 and Ba(OH)2] on the zeta potential and rheological properties of the drilling mud
(2013) Maallem, M.; Safi, Brahim; Saidi, M.; Benmounah, A.; Aboutaleb, Djamila
Effect of marble powder on the properties of self-compacting sand concrete
(2011) Bouziani, T.; Benmounah, A.; Bederina, M.; Lamara, M.
Self-compacting sand concrete (SCSC) can be regarded as a flowing sand concrete, containing as principal aggregate natural sand, which can be cast without compaction or vibration. Due to the finesses of aggregates in SCSC, it requires a high amount of fine materials than other types of concretes. This paper studies the effect of marble powder content (MP) on the properties of the sand concrete (SCSC) at fresh and hardened states. The properties of the fresh prepared mixes tested are the mini-slump flow, the V-funnel flow time and viscosity. At the hardened state, the parameter which has been determined is the 28-day compressive strength. The obtained test results show that the increase of MP content in SCSC, from 150 kg/m3 to 350 kg/m3, improves the properties at fresh state by decreasing v-funnel flow time (from 5s to 1.5s) and increasing the mini-cone slump (from 28cm to 34cm). With the use of 250 kg/m3 of MP we can reach the highest initial viscosity while retaining good fluidity at high rotational speeds, compared to the MP contents of 150 kg/m3 and 350 kg/m3. In other hand, the 28-days compressive strength decreases with an increase of MP content
Effect of polymer concentration on the rheological properties of polyelectrolyte solutions
(International Multidisciplinary Scientific Geoconference, 2014) Benyounes, Khaled; Mellak, A.; Benmounah, A.; Oubraham, C.
Effect of size and stacking of glass fibers on the mechanical properties of the fiber-reinforced-mortars (FRMs)
(2011) Saidi, M.; Safi, Brahim; Benmounah, A.; Aribi, C.
In modern day construction practice, repair and rehabilitation of structures have taken a prominent role. Indeed, the recent trend of rehabilitating and strengthening unreinforced masonry reinforced with glass fibers. In this paper, the use of fiber-reinforced-mortars (FRMs) is proposed for construction rehabilitation and reconstruction applications. A single type of fiber (glass fiber) with different length is considered; short, long and mixed. Several specimens mortars reinforced with fibers are tested in compression and flexure. Also, the stack and the microstructure of the interface glass fibers-matrix cementitious of the reinforced specimen, was examined. The results showed a remarkable increase in the mechanical resistances (50%), an important reduction of the brittleness of the reinforced mortars (lengthening higher than 40%) and a good ductility. That made it possible to increase considerably the safety of our constructions with a better esthetic aspect
Effect of the ce content on a nuclear waste glassy matrix in the system SiO2-Al2O3-CaO-MgO-ZrO2-TiO2, synthesized at a low melting temperature
(DAVID PUBLISHING, 2013) Nour-el-Hayet, Kamel; Moudir, D.; Ziane, K.; Djerridi, A.; Mouhamou, S.; Benmounah, A.; Souag, Rafika; Taouinet, M.; Ait-Amar, H.
Aluminosilicated glasses containing Zr and Ti metals have satisfactory properties, and may be suitable as nuclear glasses, dedicated for storage of radioactive waste solutions. This study summarizes the synthesis of a glassy matrix in the system: SiO2-Al2O3-CaO-MgO-ZrO2-TiO2. Ce element was added as an actinide surrogate. The effect of Ce addition on the glass structure is investigated, for Ce contents ranging between 0 and 15 wt.%. For the whole of glasses, a double melting at 1,350°C during 5 h gave monophasic homogeneous glasses. Both X-ray diffraction and scanning electron microscopy analyses reveal a pure amorphous structure. Most of the basic properties increase with the glass Ce content, the Archimedes density from 2.827 to 3.049 g/cm3, and Vickers indentations from 680 to 862 HV. Oxygen molar volumes are not affected by the glasses Ce contents. The differential thermal analysis show that the glass transformation temperature decreases with the Ce content, and with the heavy elements content. The optical absorption spectroscopy study shows that the Nd cations environment is not altered by the glasses Ce concentration. A preliminary corrosion test leads to low dissolutions of Si, Ca and Zr, estimated by ICP analyses to few ppms. Out coming investigations are in course for further glasses network characterizations
Effect of the iron concentration on the properties of an aluminosilicate glass used for storage of radioactive waste
(PARLAR SCIENTIFIC PUBLICATIONS (PSP), 2016) Moudir, D.; Ikhaddalene, Soumia; Kamel, N.; Benmounah, A.; Zibouche, Fatima; Mouheb, Y.; Aouchiche, F.
Effects of alkaline and alkaline-earth ions on the rheological behavior and zetametric study of two cement pastes (artificial cement portland-CEMI and cement resistant to the sulfates-CRS) with the polynaphthalene sulfonate (PNS)
(2012) Kheribet, R.; Samar, M.; Benmounah, A.; Safi, Brahim; Said, M.
The use of admixtures which tends to be generalized in the formulation of self-compacting concrete (SCC), requires taking into account the chemical co mposition of cement, particularly its content of SO 3 , which can inhibit or restrain the effect of these a dmixtures (superplasticizers). For more information of the compatibility problem of cement-superplasticize r, the rheological tests with a rheometer-AR2000 and measurements of zeta potential with a Zêtasiser -2000 were used in this study. In order to understand this phenomenon due to the presence of S O 3 in cement, we propose to evaluate the action of alkaline and alkaline-earth ions, incorporating different types of additions (K + , Na + , and Ca 2+ ) to the cement pastes. To achieve this, our work will conce rn the study of rheological properties and physical characteristics of the pastes obtained using two ty pes of cement (C1: Cement Resistant to the Sulfates (CRS) and C2: CEMI). This experiment will focus on two reports: Water/Cement ( W/C) = 0.30 for which the polynaphthalene sulfonate (PNS) is used as supe rplasticizer and W/C = 0.50 (without superplasticizer). The results show that the presen ce of sulfate leads to different rheological behavi ors which are function of sulfates and the cements used
Effets des sulfates sur le comportement rhéologique des pâtes cimentaires
(2009) Benmounah, A.; Samar, M.; Kheribet, R.; Saidi, M.; Safi, Brahim
L’utilisation des adjuvants qui tend à se généraliser dans la formulation des bétons autoplaçants, nécessite la prise en compte de la composition chimique du ciment, et plus particulièrement de sa teneur en SO3 qui peut inhiber ou limiter l’action de ces adjuvants (superplastifiants). Dans le but d’apporter notre contribution à la compréhension de ces phénomènes dus à la présence de SO3 dans le ciment , nous nous proposons d’évaluer l’action de certains sulfates en incorporant des ajouts sulfatés de natures différentes, à la pâte de ciment. A cet effet, notre travail aura trait à l’étude des propriétés rhéologiques et des caractéristiques physiques des pâtes obtenues à base de deux types de ciment, en l’occurrence, le CPA et le CRS. L’expérimentation portera sur deux rapports : E/C =0,30 pour lequel le polynaphtalène sulfonate (PNS) est utilisé comme superplastifiant et E/C = 0,50 (sans superplastifiant). Les résultats obtenus montrent que la présence des sulfates entraîne des comportements rhéologiques différents qui sont fonctions de la nature des sulfates et des ciments utilisés
Evaluation de la thixotropie des ciments destines a la cimentation des puits de pétrole dans les zones a pertes : Effet du plâtre et du laitier de hauts fourneaux
(2010) Bouziani, T.; Makhloufi, Z.; Benmounah, A.; Bedrina, M.