Université Mouloud Mammeri de Tizi Ouzou (UMMTO): Research Review of Sciences and Technologies
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The Role of Ai-Supported Models in the Damage Detection Process of Historical Buildings: A Review
Full text linkThe sustainable preservation of historical buildings is of great importance for the future preservation of cultural heritage. The advent of artificial intelligence (AI) technologies in recent years has led to significant advancements in damage detection for historical buildings, resulting in enhanced efficiency and speed. Consequently, there has been a notable proliferation of artificial intelligence-based damage detection models in the extant literature. This study aims to examine the role of artificial intelligence-supported models in the damage detection process of historical buildings. A comprehensive review of the extant literature was conducted, encompassing a total of 97 case studies. The analysis revealed that damages to historic buildings can be categorized into three primary classes: disaster damages, structural damages (including structural health monitoring), and surface damages. The study provides a comprehensive analysis of damage detection methods in historical buildings, offering significant insights into the performance of existing artificial intelligence models in each category. The effectiveness of artificial intelligence-supported models in damage detection for historical buildings has been evaluated, and the strengths and shortcomings in the existing literature have been identified. The study further highlights aspects that require improvement in existing approaches and provides recommendations for future research endeavors. This study emphasizes the significance of artificial intelligence-based damage assessment methods for the conservation of historical buildings, laying the groundwork for future research in this field
Production of eco-friendly self-compacting concrete with recycled concrete aggregate
No full textIn recent years, recycled aggregate concrete (RAC) has become a major focus of research due to its positive environmental impact. The objective of this paper is to investigate the influence of dosage of recycled sand and gravel on the fresh properties of self compacting concrete (SCC). Experimental program was conducted on SCCs made with different rates of substitutions (25, 50, 75 and 100%) of natural sand and gravel (NS, NG) with recycled sand and gravel (RS, RG) by volume. All mixtures were obtained with a constant W/C ratio of 0.38, sand-to-mortar (S/M) ratio of 0.5 and a superplasticizer dosage of 1.5% of binder by weight. For fresh properties, tests were conducted for slump flow, V-funnel, L-box and resistance to segregation. Rheometer apparatus in the rheological testing of fresh SCC was used to determine the rheological parameters. The results indicated that an optimum replacement level of recycled sand and gravel of 50% can be achieved without adversely affecting key fresh concrete properties, including filling ability, passing ability, and segregation resistance. In addition, a clear correlation was established between the empirical and rheological parameters of the self-compacting recycled aggregates concrete
Valorisation de la poudre de marbre comme substitut partiel au sable dans la formulation d’un mortier autoplaçant
No full textThis study investigates the use of marble powder (MP), a local industrial by-product, as a partial sand substitute (7–25%) in self-compacting mortar (SCM) formulations incorporating crushed calcareous sand (fineness modulus = 3.0). Fresh-state tests (mini-cone flow, V-funnel) show that MP incorporation increases flow diameter while raising flow time, reflecting modified rheological behavior. Mechanically, compressive strength improves progressively with substitution rate, while flexural strength remains comparable to the reference mix, with optimal performance at 22%. Durability indicators — immersion absorption and capillary sorptivity — both decrease at moderate substitution levels (7–12%), indicating microstructural densification. Beyond 22%, a decline in durability performance is observed. These results confirm that MP can effectively correct the granulometric deficiency of coarse calcareous sand while enhancing SCM properties within a circular economy framework.Cette étude évalue l’utilisation de la poudre de marbre (PM), coproduit industriel local, comme substitut partiel du sable (7–25%) dans des mortiers autoplaçants (MAP) intégrant un sable calcaire concassé à module de finesse élevé (MF = 3.0). Les essais à l’état frais montrent que l’ajout de PM augmente le diamètre d’étalement tout en allongeant le temps d’écoulement au V-funnel. Sur le plan mécanique, la résistance à la compression progresse avec le taux de substitution, avec une performance optimale à 22 %, tandis que la résistance à la flexion reste comparable au témoin. La réduction de l’absorption par immersion et de la sorptivité capillaire pour des taux de 7–12 % atteste une densification microstructurale favorable à la durabilité. Au-delà de 22 %, une dégradation de ces indicateurs est observée
To study the metallurgical and mechanical properties of SMAW dissimilar weld joints between AISI 1020 carbon steel and AISI 410 martensitic stainless steel using three distinct fillers
Full text linkThis study investigates the metallurgical and mechanical properties of dissimilar weld joints between AISI 1020 carbon steel and AISI 410 martensitic stainless steel, fabricated using three distinct filler metals: austenitic AWS 309L and AWS 316L, and martensitic AWS 410. The weldments were comprehensively evaluated through tensile testing, Charpy V-notch impact testing, microhardness profiling, and microstructural analysis to determine the optimal consumable for this application. The results demonstrated the superior performance of the AWS 309L filler, which yielded the highest ultimate tensile strength (410.5 MPa) and greatest impact toughness (24.2 J). This enhanced performance was attributed to the formation of a desirable duplex microstructure of austenite and distributed delta ferrite in the fusion zone. Conversely, the weldment made with the matching AWS 410 filler, despite exhibiting the highest hardness (peak 532 HV), showed low impact toughness (18.7 J) and moderate tensile strength (371.3 MPa), indicating a brittle, untempered martensitic structure susceptible to failure. The AWS 316L filler produced the lowest mechanical properties overall. The findings conclude that AWS 309L is the most suitable filler metal, producing a robust and damage-tolerant joint, whereas the AWS 410 filler is inappropriate for this application in the as-welded condition due to its inherent brittleness
Predicting the Compressive Strength of UHPFRC Using Machine Learning and Soft Computing Models: Optimization of Fiber Content and Additives
Full text linkUltra-high-performance fiber-reinforced concrete (UHPFRC) is a relatively new material known for its superior mechanical properties, particularly its compressive strength (CS), making it suitable for advanced structural applications. Traditional experimental methods for predicting CS are time-consuming and costly. In this study, a dataset of 276 samples with 12 input parameters was compiled from existing literature to develop predictive analytical models. The input variables include cement, sand, water, superplasticizer, silica fume, fiber content, water–binder ratio, water–cement ratio, curing age, fiber aspect ratio, temperature, and fiber volume. The reported CS values range from 90 to 186 MPa. Five modeling techniques—Linear Regression (LR), Log Base Regression (LBR), Nonlinear Regression (NLR), M5P-tree, and Artificial Neural Network (ANN)—were employed to predict the compressive strength of UHPFRC. Among these models, ANN demonstrated the highest prediction accuracy across all evaluation criteria, followed by the M5P-tree model. Residual error analysis confirmed that the ANN produced the lowest prediction error. Sensitivity analysis revealed that temperature, curing age, and superplasticizer content significantly influence CS. Optimization results indicated that a fiber content between 2.05% and 2.09% yields maximum compressive strength. These findings provide valuable insights for optimizing UHPFRC mix design using machine learning approaches
The Potential of Using Waste Rock and Tailings from Gold Mining in Concrete Production
Full text linkIn an effort to lessen the negative effects of mining on the environment and advance sustainability, this study explores the use of gold mining waste rock and tailings (GMWRT) as alternatives to conventional aggregates in concrete production. The study examined the chemical, physical, mechanical properties and water absorption of six concrete mixtures with varied levels of GMWRT (from 0% to 25%). X-ray fluorescence spectrometry and sieve analysis were used to determine the chemical composition and particle size distribution. After 28 days of curing, tests were conducted for compressive strength, flexural strength, and water absorption. The chemical analysis revealed that GMWRT had 80.37% SiO₂, Al₂O₃, and Fe₂O₃, exceeding the 70% pozzolanic material threshold established by ASTM C618. The findings showed that when GMWRT replaced conventional aggregates by 0 to 25%, the compressive strength (CS) went from 31.40 to 17.50 N/mm2, which decreased as the proportion of the GMWRT increased. Although there was a decrease in compressive strength, the values fell within the acceptable range of 17 to 28 N/mm² for various applications. The flexural strength (FS) followed the same pattern as the CS, but it was higher than the required 3.13 N/mm2, which means it can be utilised practicably. GMWRT concrete demonstrated enhanced resistance to chloride attack and reduced water absorption, making it viable for coastal construction. ANOVA and other statistical approaches revealed that the results were important. The analysis reveals that GMWRT can partially replace traditional aggregates. This is excellent for the economy and the environment. This method encourages environmentally friendly construction practices and offers developing nations like Ghana an eco-friendly way to handle mining waste
Smart expressways in Vietnam: An architectural proposal
No full textSmart expressways represent an emerging direction in modern transportation, where digital technologies are embedded into road infrastructure to improve mobility, safety, and sustainability. By integrating advanced communication, sensing, and automation systems, they aim to meet the rising demands of urbanization and future mobility trends. Vietnam’s expressway network, though expanding, remains conventional and continues to face congestion, safety concerns, and limited readiness for digital transformation. This study evaluates how smart expressway concepts can be adapted and implemented within the nation’s socio-economic context. The research combines a review of Vietnam’s current infrastructure with an assessment of digitalization initiatives in the transport sector. It also draws on international case studies, adapting relevant lessons to identify technological opportunities—such as IoT, AI, V2X communication, and ITS—while acknowledging challenges in financing, governance, and institutional capacity. The results emphasize both the benefits of smart expressway adoption, including greater efficiency, reduced environmental impacts, and enhanced safety, and the barriers that must be addressed. The study concludes by proposing a practical roadmap and architectural framework suited to Vietnam’s developmental stage, providing strategic guidance for sustainable and future-ready mobility
Effet des caractéristiques d'élasticité sur la déformabilité d'un massif de sol lors de l'excavation d'un ouvrage souterrain.
No full textThe excavation of underground structures, particularly shallow ones, causes significant deformations of the soil mass, potentially leading to instabilities both near the structure and at the surface. Predicting these movements and implementing stabilization measures remains complex due to the numerous factors involved, such as geological, geotechnical, and hydrogeological conditions, as well as the dimensions and depth of the excavation. The soil mass's response depends primarily on its capacity to deform without failure. This work investigates the influence of elasticity parameters on soil deformability during shallow excavation. Finite element modelling enables a parametric analysis of stiffness. The results demonstrate a high sensitivity of displacements to elastic parameters and highlight the need for reliable stiffness estimation to accurately predict soil mass behaviour and ensure the safety of underground structures.Le creusement d’ouvrages souterrains, notamment peu profonds, provoque des déformations importantes du massif de sol, pouvant entraîner des instabilités à proximité de l’ouvrage et en surface. La prévision des mouvements et des mesures de stabilisation reste complexe en raison des nombreux facteurs impliqués, tels que les conditions géologiques, géotechniques et hydrogéologiques, ainsi que les dimensions et la profondeur de l’excavation. La réponse du massif dépend principalement de sa capacité à se déformer sans rupture. Ce travail étudie l’influence des paramètres d’élasticité sur la déformabilité du sol lors du creusement d’une excavation peu profonde. Une modélisation par éléments finis permet de réaliser une analyse paramétrique de la rigidité. Les résultats montrent une forte sensibilité des déplacements aux paramètres élastiques et soulignent la nécessité d’une estimation fiable de la rigidité pour prédire correctement le comportement du massif et assurer la sécurité des ouvrages souterrains
Influence of Silicon Nitride on the Electrochemical Corrosion Features of Functionally Graded Aluminium Composite
No full textFunctionally Graded Composites (FGCs) represent an evolving category of engineering materials distinguished by their property variations along a designated direction, specifically designed to fulfill targeted applications. This study involved the fabrication of Al (Aluminium) A356 alloy strengthened with Silicon Nitride (Si₃N₄) FGC using a vertical centrifugal casting technique. The optical microscope, X-ray Diffraction (XRD), and Vicker’s microhardness evaluator examined the gradient dissemination of Si₃N₄ ceramic particles. An electrochemical corrosion study was conducted on various regions of the FGC utilizing a potentiostat, examining the heat-treated situation in comparison to the as-cast situation. Under heat-treated situations, the ceramic concentrated zone exhibited the smallest Corrosion Rate (CR) of 0.0109 mmpy, representing a reduction of 75% compared to the 0.0439 mmpy observed in the matrix concentrated zone under as-cast conditions. Additionally, the Si₃N₄ particles functioned as a protective barrier within the ceramic concentrated zone, decreasing CRs compared to further regions
A high-performance and low cost nitrogen-containing gray cast iron
Full text linkTo meet the demand for high-strength gray iron castings while lowering casting production costs, nitrogen micro alloyed gray cast iron with manganese nitride inoculant was developed, and the effects of manganese nitride addition on its microstructure, mechanical properties, and casting cost were investigated. The test results show that with different manganese nitride additions, the graphite flakes have round and blunt ends and short, thick, and slightly curved shapes; as the nitrogen content in the iron increases, the graphite forms become shorter and curved, and the pearlite content increases, which is conducive to improving the strength and hardness of gray cast iron. Excess nitrogen content in castings causes nitrogen porosity defects, which significantly degrades the material properties. The addition of alloying elements such as Cu and Sn can be reduced by adding an appropriate amount of manganese nitride to the process, and the casting cost can be reduced by 180 RMB/ton to realize low-cost production of high-performance gray cast iron