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RÉSUMÉL’Algérie, depuis longtemps, souffre d’une pénurie des ressources en eau. La stratégie de l’état algérien consiste à augmenter les stocks d’eau en adoptant plusieurs solutions, parmi lesquelles, il y a la construction des barrages et des retenues d’eau. Mais cette solution est confrontée aux conditions météorologiques qui favorisent les pertes par évaporation, surtout dans les régions arides. Ce travail consiste à présenter les premiers essais algériens sur la préservation des plans d’eau, et augmenter ses stocks par la réduction de l’évaporation, en utilisant des substances chimiques à longue chaîne, capable de former une pellicule à l’interface air/eau, appelée « film mono-moléculaire ».Les résultats obtenus ont permis d’enregistrer des taux de réduction de l’évaporation significatifs. Ces taux varient en fonction de la substance utilisée, la durée entre deux applications de la substance et des conditions météorologiques de la région d’étude. 相似文献
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Souhila Chabane Djamel Machane Mohamed Yacine Tebbouche Fatma Khaldaoui El-Hadi Oubaiche Rabah Bensalem Armand Mariscal 《Arabian Journal of Geosciences》2017,10(3):69
The Dar El Beida area, situated in the Mitidja basin, in the north central Tellian Atlas is characterized by its Plio-Quaternary sediments. The site effect analysis in this zone surrounding Algiers city is very important. The soil is constituted from recent soft sediments capable of amplifying seismic motion. Indeed, the analysis thanks to the ratio H/V ambient vibration method confirms these assumptions. An electric resistivity tomography strengthened the results obtained from ambient vibration for site characterization. This demonstrates once again the more or less homogeneous character of formations in this area. However, strongly amplifying its sediments largely explains the seismic acceleration of 0.52 g recorded following the 2003 Boumerdes earthquake. 相似文献
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Brahim Meziani Djamel Machane Abderrahmane Bendaoud Ghani Cheikh Lounis El-Hadi Oubaiche Souhila Chabane Rabah Bensalem Hakim Moulouel 《Arabian Journal of Geosciences》2017,10(5):117
The Ain Turck (Bouira) landslide, in north-center Algeria, is one of the numerous instabilities recorded along the Lakhdaria-Bouira section of the 1200-km-long east-west Algerian highway. The locality of Ain Turck is known for its unstable slopes characterized by a very rough morphology with steep slopes (20 to 25%). This slide threatens the inhabitants of the Ibournanen village, located down the unstable slope, where parts of some houses have fallen into ruin, while others are cracked. It is characterized by an active movement extending over a more or less important slope, of the order of a hundred meters. The land mobilized by this movement corresponds to the layer of shale clays and clays overlaid by a backfill, placed there following the east-west highway works. Geological, geomorphologic, and geotechnical analysis allows determining the soil instability probably related to earthworks during the construction of the highway section a few years earlier, followed by a particularly rainy season in 2012. Acquisitions of ambient seismic noise and H/V ratio processing, as well as the acquisition of an electrical resistivity profile at the instability site, have reinforced our preliminary interpretations of depth and geometry of the sliding surface. 相似文献
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Djamel Bengora Lotfi Khiari Jacques Gallichand Noureddine Dechemi Silvio José Gumiere 《国际泥沙研究》2018,33(4):518-524
The capacity of water reservoirs may be considerably reduced by sediment transport and accumulation. This phenomenon may occur quickly in regions prone to erosion, such as Hammam Debagh Dam region in Algeria. For better management of water resources, it is important to estimate the volume of a reservoir by regular and frequent topo-bathymetric surveys. Topo-bathymetric surveys with a high point measurement density are expensive and time-consuming. To reduce this expense and to increase the frequency of topo-bathymetric surveys, it is required to optimize their size and density. The complete survey of the reservoir created by the Hammam Debagh Dam in Algeria was examined in comparison with 19 reduction subsets using geostatistics. The study showed that the complete dataset of 32,164 points, corresponding to a density of 42 points ha-1 could be reduced to 10,000 points, i.e. 13 points ha-1, without affecting the estimation of the water volume in the reservoir. This reduction could considerably simplify the work load, reduce the expenses to do these surveys, and, therefore, allow for an increased frequency of topo-bathymetric surveys. 相似文献
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Mohamed Amine Boukhedimi Amina Louni-Hacini Youcef Bouhadad Jean-François Ritz Djamel Machane Azzeddine Benhamouche Hamid Bourenane 《Journal of Seismology》2017,21(3):539-549
Coastal Quaternary deposits of western Oranie show typical soft-sediment deformations including sedimentary dykes, sand volcanoes, sismoslumps, thixotropic bowls, thixotropic wedges, diapir-like structures, and faults grading. Field observations indicate that these deformations exist at several levels of the studied deposits along the west Oranian coast. This study demonstrated that these structures are earthquakes-related, by analysis of potential trigger sources. Several arguments demonstrate the seismic origin: the depositional environment rich in water that located in an active tectonic region, the thixotropic nature of deformations and their large vertical and horizontal diffusion in the Quaternary series consistent with a seismic recurrence. This allows characterizing these Quaternary soft-sediment deformations as seismites that were triggered by earthquakes. 相似文献
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La majorité des surfaces mises en valeur dans les zones arides et semi-arides de l’Algérie reposent sur des nappes phréatiques très minéralisées dont le niveau est proche de la surface du sol (0–1,5 m). En présence de conditions climatiques très sévères, le processus d’évaporation de ces nappes contribue en grande partie à la salinisation des terres et la dégradation du milieu. Les résultats de l’étude de l’évaporation de la nappe phréatique de la région de Ouargla montre que l’évaporation diminue au fur et à mesure que le niveau de la nappe s’éloigne de la surface du sol. L’évaporation de la nappe est maximale et égale à l’évaporation du plan d’eau lorsque le niveau de cette nappe est situé dans la couche 0–0,6 m et devient minimale au dessous de 1,7 m. Pour une meilleure mise en valeur des terres et une production agricole élevée, il est nécessaire de connaître la profondeur critique de la nappe phréatique, profondeur pour laquelle l’évaporation est faible et par conséquent le dépôt de sels est faible dans les sols à texture sableuse de la région aride de Ouargla. 相似文献
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Mehdi A. Guemache Jean-Luc Chatelain Djamel Machane Sihem Benahmed Leila Djadia 《Journal of African Earth Sciences》2011,59(4-5):349-358
The goal of this paper is to document causes of the failure of stabilization measures undertaken for stabilizing a complex landslide threatening the Sidi Rached viaduct in Constantine, Algeria. Since the first instabilities, documented in 1910 during its construction, significant disturbances have been regularly observed on its eastern part and reinforcements carried out were only temporarily effective. Observed disturbances are inherently related to the fact that the eastern abutment and the three subsequent piers are built on unstable Maastrichtian marls whereas the remainder of the viaduct rests on stable Turonian limestone. The five main factors controlling the activation of the failure process are reviewed: (1) geomorphology, (2) geology, (3) human activities, (4) climate, and (5) seismicity. Data interpretation of two inclinometer surveys carried out close to the eastern abutment shows that the unstable mass moves westward, towards the Rhumel gorges. The main slip surface is located in the Maastrichtian schistose marl, at a depth ranging from about 8 m (west) to about 30 m (east). This translational slide is associated with a settling phenomenon due to the petrophysical properties of the unstable marl. 相似文献
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Advantages of the analytic element method for the solution of groundwater management problems 总被引：1，自引：0，他引：1
In the simulation‐optimization approach, a coupled optimization and groundwater flow/transport model is used to solve groundwater management problems. The efficiency of the numerical method, which is used to simulate the groundwater flow, is one the major reason to obtain the best solution for a management problem. This study was carried out to examine the advantages of the analytic element method (AEM) in the simulation‐optimization approach, for the solution of groundwater management problems. For this study, the AEM and finite difference method (FDM) based flow models were developed and coupled with the particle swarm optimization (PSO)‐based optimization model. Furthermore, the AEM‐PSO and FDM‐PSO models developed were applied in hypothetical as well as real field conditions to address groundwater management problems and the results were compared. For the real field situation, the models developed were applied to the Dore River basin in France to minimize the installation and operational cost of new pumping wells taking the location and discharge of the pumping wells as decision variables. The constraints of the problem were identified with the help of stakeholders and water authority officials. The AEM flow model was developed to facilitate the management model particularly when at each iteration, the optimization model calls for a simulation model to calculate the values of groundwater heads. The results show that, at some points, the AEM‐PSO model is efficient in identifying the optimal location of wells and consequently results in optimal costs, sometimes difficult when using the FDM. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Bearing Capacity of Embedded Strip Footings on Cohesionless Soil Under Vertical and Horizontal Loads
Hadjer Yahia-Cherif Abdelhak Mabrouki Djamel Benmeddour Mekki Mellas 《Geotechnical and Geological Engineering》2017,35(2):547-558
In the last decades a few attention was given to the evaluation of the bearing capacity of embedded footing under inclined loads on a frictional soil. This paper focuses on a numerical study using the finite-difference code Fast Lagrangian Analysis of Continua (FLAC), to evaluate the bearing capacity of embedded strip footing on a frictional soil. The soil is modeled by an elasto-plastic model with a Mohr–Coulomb yield criterion and associative flow rule; the effect of non-associativity of the soil on the bearing capacity is also investigated. The effect of the embedment is estimated though a depth factor, defined as a ratio of the bearing capacity of a strip footing at a depth D to that of a strip footing at the ground surface. The inclination effect is estimated by inclination factors, defined as the ratio of the limit vertical load for a footing under inclined loading to that of the vertically loaded footing. Both swipe and probe analyses were carried out to identify the vertical force–horizontal force (V–H) failure envelope. The results have been compared with those available in the literature. 相似文献