Université Mouloud Mammeri de Tizi Ouzou (UMMTO): Research Review of Sciences and Technologies
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معارضة النص وإنتاج النص البديل *رمل الماية لواسيني الأعرج*
No full textThe tradition text is considered as a foundamental one in the novel. Which call for the production of a new culture and an alternative text, the teller is searching a new ways for the narrative text by penetrate the original text either by inviting and discussing it or by writing a new text based on it.This is what we are going to discover at wassini’s novel
Improving properties of modified clay with cement containing random chicken feather fibers
Get PDFOver the past decades, the poultry meat processing industry’s growth has generated a huge amount of feather “waste”. This waste has given rise to a number of environmental concerns and had a low value-being when used in many industrial applications. Promoting the use of sustainable materials is now a pole of interest in engineering construction. Aiming to recover this waste in enhancing the properties of problematic soils, an experimental study is conducted using these materials. An earth material named Zebabdja clay is treated by the cement to improve its properties. The inclusion of waste byproducts such as chicken feather fibers would improve the characteristics of the soil with low load bearing capacity. The present work attempts to valorize this kind of natural fiber in the field of building and solve an environmental problem using local materials. The control parameters evaluated herein include cement content (6%, 8%, 10% et 12%) and chicken feather fibers contents (1%, 2% et 3%). The unconfined compressive and direct shear tests were measured at different curing times. The results found show that 10% is the needed amount of cement to be used in order to stabilize the clayey soil treated. An increase in chicken feather fibers up to 2% indicates an improvement of the mechanical performances of the clayey soil, which may constitute a very interesting engineering solution for the weak soil
Etude de la pouzzolanicité de deux argiles de Kindia (Guinée) en vue de leur utilisation dans la formulation de liant hydraulique
Get PDFThis work presents, firstly, the results of pozzolanicity tests on two varieties of clay, codified respectively ABD and ARD, taken at Débélé. In a second step, the physical properties of the mortars obtained from these two clays by substitution of cement at a rate of 20% are presented and discussed. The mechanical behaviour of the mortars shows acceptable variations with apparent densities between 1.800 and 2.090 g/cm3. The mechanical resistance is lower than that of the control mortar for hybrids based on raw clays, but those of hybrids based on calcined clays are higher than that of the control mortar beyond the 28th. These results attest to the pozzolanic character of the Débélé clays and constitute a contribution to their valorisation in the formulation of hydraulic bindersCe travail présente, dans un premier temps, les résultats d’essais de pouzzolanicité de deux variétés d’argile, codifiées respectivement ABD et ARD, prélevées à Débélé. Dans un second temps, les propriétés physiques des mortiers obtenus à partir de ces deux argiles par substitution du ciment au taux de 20 % sont présentées et discutés. Le comportement mécanique des mortiers manifeste des variations acceptables avec des masses volumiques apparentes comprises entre 1,800 et 2,090 g/cm3. Les résistances mécaniques restent inférieures à celle du mortier témoin pour les hybrides à base d’argiles brutes, mais celles des hybrides à base d’argiles calcinées sont supérieures à celle du mortier témoin au-delà du 28ème. Ces résultats attestent le caractère pouzzolanique des argiles de Débélé et constituent une contribution pour leur valorisation dans la formulation des liants hydrauliques
Reliability evaluation of 2D semi-rigid steel frames accounting for corrosion effects
Get PDFNowadays, steel frames are widely used in civil and industrial engineering structures. The design process for steel frames with semi-rigid beam-column connections is an interesting topic for designers and researchers. However, the current design codes purely deal with the structural reliability at the pristine and the degradation of steel due to corrosion is not specified. This study proposes a procedure for evaluating the reliability of two-dimensional semi-rigid steel frames considering corrosion effects. A series of Monte Carlo simulations are performed to evaluate the reliability of the corroded steel structures. The random variables including corrosion phenomenon, semi-rigid connection, and applied load, are considered in the proposed method. The safety deterioration of the steel structures due to the corrosion phenomenon until 50 years is obtained. Additionally, the effects of input parameters, which are safety factors and coefficients of variation, on the reliability of structures are examined in the present study. Finally, a verification of this study and previous results is performed, highlighting the capability of the proposed method.
ظاهرة الإحالةفي المنهج التداوليوأثرها في تجديدتحليل الحطاب اللساني
No full textظهر المنهج التداولي كرد فعل على عجز المنهج البنيوي، الذي اقتصر فيتحليل النصوص على دراسة وتحليل العالقات البنيوية الداخلية بين العالمات اللغوية فقط مقصيا بذلك العالمات غير اللغويةمن دائرة اهتمامه؛ونتيجةذلك قصور في الفهم،وضعف ال منهجيا لسانيا من البنيوية إلى التداولية. وسنحاول في ّ اكا وترح َ ر َ في التحليل، اقتضيا ح هم القضايا التداولية؛ لحضورها في كل هذا البحث تتبع ورصد ظاهرة اإلحالة بعدها من ا القضايا التي تدرسها التداولية دون استثناء، مجتهدين في اإلجابة عن سئلة من قبيل: ا ما اإلحالة؟ وما موقعها من العالمة اللغوية، عند دوسوسير، وبيرس، وفالسفة اللغة العادية؟ سه وما مبررات إقحامها في العالمة اللغوية عند التداوليين؟ وكيف ا مت في فهم الخطاب وتحليله؟ معتمدين على المنهج التاريخي في تتبع الظاهرة، والمنهج الوصفي في وصفها وعلى داتي التحليل واالستقراء في استخالصالنتائج
Investigation of bond performance of reinforced fly ash-based Geopolymer concrete using experiments and numerical analysis
Get PDFThis study evaluates the bond performance of reinforced fly ash-based geopolymer concrete by using experiments and numerical analysis. Three types of mixture proportions along with two types of reinforcement diameter, (d12, ribbed bar) and (d14, smooth bar) mm, were selected for experimental work. The bond behaviour of reinforced geopolymer concrete is determined using the pullout test, and Finite Element Analysis (FEA). The test data indicated that the bond strength of reinforced fly ash-based geopolymer concrete increases with the increase in compressive strength. The concrete cover to diameter ratio (c/db) increases from 4.86 to 5.75 and the bond strength of all three groups of samples also increases. Besides, the bond stress-slip curves obtained by the ABAQUS software closely match the results from experimental works. Furthermore, the parametric analyses show that when the compressive strength of geopolymer concreteincreases, the bond strength of reinforced fly ash-based geopolymer concrete increases. These results are consistent with the test data
Effect of Creep and Shrinkage model in calculation of long-term deflection of three-span solid slab continuous prestressed concrete bridge
Get PDFShrinkage and creep effect significantly to the long-term deflection of prestressed concrete bridge. The proper shrinkage and creep models should be developed to meet the requirements of deflection effect calculation. There are many models have been researched and developed. Each specification, such as ASSHTO, Eurocode, ACI and CEB-FIB, has their own model of shrinkage and creep by considering different input parameters. The long-term deflection calculation is also different in each specification as a result. In this paper, several shrinkage and creep models were selected and reviewed to see the differences and compare by using popular concrete grade in Vietnamese bridge construction (C40 and C45, equivalent to 40 and 45 Mpa, respectively). Those selected shrinkage and creep models are applied in calculation of deflection for a typical three-span continuous solid slab prestressed concrete bridge. The calculation results show the significant different of long-term deflection and the ASSHTO shrinkage and creep model show the biggest deflection
Effects of ripening on the mechanical properties of the laminated alloy AlCu3Si2Mg
Get PDFPure aluminium has poor mechanical properties. For this purpose, the objective of this work is to study principally the influence of the incorporation of 3% copper, 2% silicon and less than one percent (1%) magnesium, which represent very important agents for improving the mechanical properties associated with the laminating process. In order to further increase the characteristics of this wrought alloy AlCu3Si2Mg, we have carried out heat treatments in a further step by varying the maturation time in two-hour increments over 24 hours. These different ripenings reveal a finer structure with several precipitates that prevent the movement of the dislocations. The selection of this alloy was motivated by the large number of mechanical applications in which it is widely used. The results obtained in this study show that the twelve-hour hardened state M12h is the best compromise between strength and maximum ductility.
بلاغة الجمهور في الأدب
No full textThis article suggests a research subfield that studies the rhetoric of audiences in literary works. The suggested subfield tackles the responses made by audiences in literary fiction works such as short stories, novels, plays, epics, etc. This subfield provides a new perspective to literary fiction that enables a revisiting to a huge data of classical and modern works through investigating the individual and collective responses to oppressing and liberating discourses. It, also, explores the relation between the responses of fictional characters in literary writings and the real ones in real worlds. The article combines two sections. The theoretical one introduces the proposed subfield: its scope, goals, research questions and academic importance. The second analytical section explores the rhetorical responses in an Arabic short story collection by Mohamed Al-Makhzanjy entitled ‘Sayyad AlNaseem’. I analyze the characters (non0 rhetorical responses to the discourse of oppression in five short stories to investigate their production processes, discursive structures, forms and impacts
شرح مفردات النّصوص القرائية -قراءة في كتب اللّغة العربية للسّنتين الثّانية والثّالثة من التّعليم الابتدائي-
No full textThis study sheds light on the issue of explaining difficult vocabulary in reading texts in Arabic language textbooks for primary education second and third years, including texbooks of both reform and reform of reform, and researching the criteria for selecting the difficult words in the text, the most important techniques adopted in the explanation. As well as the problems posed by this educational activity. Perhaps, most importantly is considering the extent to which the new textbooks have overcome the lapses recorded about the previous textbooks in relation to the issue of explaining difficult vocabulary. The study led to the recording of a number of deficiencies that require the reconsideration of the techniques of selecting difficult words in the textbooks and their explanation