ANTI-BACTERIAL EFFECTS OF GLYCOSIDES EXTRACT OF GLYCYRRHIZA GLABRA L. FROM THE REGION OF DJAMÂA (SOUTH-EAST OF ALGERIA)

The natural extracts of plants contain a variety of biologically active molecules. In this context, we attempted to evaluate the antimicrobial activity of some extracts prepared from the root of Glycyrrhiza glabra L., which grows in the region of Djamâa (south of Algeria). The qualitative analysis of these extracts revealed the presence of plant glycosides, which is confirmed by a quantitative analysis based on the detection test of glycosides, who demonstrated that the extracts are rich in these molecules, where the content of glycoside reached (10 %) for the ethanol extraction. The evaluation of the glycoside extract antimicrobial activity revealed a strong effect of inhibition on different strain of bacteria, when it was responsible for a large zone of inhibition of the bacterial strain Pseudomonas aeruginosa, compared to Escherichia coli and staphylococcus aureus. From these results, we can say that the glycoside extracts have different antibacterial effects depending on the species

Modelling of fresh properties and strength activity index with microstructure characterisation of ternary cement incorporating waste glass and granulated blast furnace slag

Research in innovative construction materials has focused on utilising supplementary materials in cementitious composites to promote sustainable development and reduce CO2 emissions. Within this context, this study aims to investigate the fresh properties and assess the pozzolanic activity of ternary blended cement by incorporating two industrial waste materials, namely waste glass (WG) and granulated blast furnace slag (GBS), as cement replacements up to 30%. A mixture design approach was employed for composition optimisation, and mathematical models were implemented to achieve this. XRD and SEM/EDS analyses were conducted to examine the structure and composition of the cementitious matrix.The results indicate that the setting time was prolonged compared to the reference mixture. Furthermore, based on the results of the SAI (Strength Activity Index) test, an acceptable level of strength development was demonstrated, confirming that WG and GBS possess the potential to replace cement while meeting the minimum strength requirements outlined in the specifications. Microstructure analyses revealed good adhesion between WGP, GGBS, and the cementitious binder. This research contributes to the development of eco-efficient binders that exhibit increased cement replacement ratios and qualities comparable to, or even superior to, traditional cement systems

Experimental characterization of a new sustainable sand concrete in an aggressive environment

The scarcity of building materials and the shortage of coarse aggregates which represents the main component of concrete is a problem in the most third world countries, especially in the vast desert areas in Algeria.  In desert conditions where the environment suffers from the phenomenon of rising water and aggressive soil; the evaluation of existing abundant Sand Dune and its compensation for naturel Sand could be a very good economic solution. Several researches at the local and the global levels confirm that Sand Dune can be exploited in concrete after a granular correction. In this paper, a new Sand resource (Oued El-Ratm, El Oued-Algeria) is proposed as an alternative of natural Sand to perform a Sand Concrete. The findings of this experimental study show that the Sand Concrete based on this new resource of sand dune of the Algerian desert has a good resistance when used in the ambient Saharan aggressive conditions

Study of the Mechanical Properties of Gypsum Tuff –Dunes Sand Mixture for use in Saharan Road Construction

This work fits into the context of minimizing the use of non-renewable and depleting natural resources, such as gypsum tuff. Its objectives are to study the mechanical properties of a mixture of gypsum tuff (GT) and sand dunes (SD) in order to have the possibility of integrating it into Saharan pavements. The results obtained showed an improvement of Bearing index (Immediate bearing index, IBI and Bearing index after soaking, IBas ), evaluated by the CBR test, of the mixture composed of 80% of GT + 20% SD in comparison with that of the gypsum tuff  alone. Whereas its simple compressive strength decreased slightly at the age of 28 days. This decrease led us to treat the mixture with lime and to examine the evolution of the compressive strength according to the curing time

EFFET DE LA TENEUR EN FIBRES DE PALMIER DATTIER ET DE LA CONTRAINTE DE COMPACTAGE SUR LES PROPRIÉTÉS DES BLOCS DE TERRE COMPRIMÉE

Afin de valoriser les matériaux locaux, de contribuer à la réduction des coûts de construction et de l’énergie consommée pour le chauffage ou la climatisation, des fibres de surface du palmier dattier mâle (FSPDM) ont été utilisées pour stabiliser les blocs de terre comprimée (BTC). L'objectif principal de ce travail est l'étude de l'effet de la teneur en fibres de palmier dattier et de la contrainte de compactage sur les propriétés mécaniques du BTC renforcée par ces fibres. L'étude s’est focalisée aussi sur sa sensibilité à l'eau, en étudiant son absorption totale. Dans ce cadre, on a utilisé trois teneurs en ciments (5, 6.5 et 8 %), quatre teneurs en fibres (0.05, 0.1, 0.15 et 0.2 %) du poids du mélange sec et trois contraintes de compactage (1.5, 5 et 10 MPa). Les résultats indiquent qu’il y a une amélioration de la résistance à la compression sèche des blocs avec 0,05% en fibres, 8 % en ciment et une contrainte de compactage de 10 MPa. Mais pour le reste des cas étudiés, l'ajout de fibres a un effet négatif sur les propriétés du BTC. Cette étude a montré aussi que l’augmentation de la contrainte de compactage conduit à l’amélioration de la résistance à la compression sèche In order to valorise locals materials, to contribute to the reduction of construction costs and energy consumed for heating or conditioning, the male date palm surface fibers (MDPSF) have been used to stabilize the compressed earth blocks (CEB). The main objective of this work is the study of the effect of date palm fibers content and compaction pressure on the mechanical properties of CEB reinforced with this fibers. The study also focused on its sensitivity to water, by studying its total absorption. In this framework, three cement contents (5%, 6.5% and 8%), four fibres contents (0.05%, 0.10%, 0.15% and 0.20%) of the weight of the dry mixture are used, and compacted the soil with a static loading by applying three compacting stresses (1.50 MPa,5 MPa and 10 MPa). The results indicate that, an improvement in dry compressive strength of the blocks with 0.05% fibres content and 8% cement content and compacted at 10MPa pressure, is recorded. But for the remaining cases studied, the addition of fibers has an adverse effect on the properties of CEB. This study also showed that the increase in compaction stress leads to the improvement of dry compressive strengt

Modelling of fresh properties and strength activity index with microstructure characterisation of ternary cement incorporating waste glass and granulated blast furnace slag

Research in innovative construction materials has focused on utilising supplementary materials in cementitious composites to promote sustainable development and reduce CO2 emissions. Within this context, this study aims to investigate the fresh properties and assess the pozzolanic activity of ternary blended cement by incorporating two industrial waste materials, namely waste glass (WG) and granulated blast furnace slag (GBS), as cement replacements up to 30%. A mixture design approach was employed for composition optimisation, and mathematical models were implemented to achieve this. XRD and SEM/EDS analyses were conducted to examine the structure and composition of the cementitious matrix. The results indicate that the setting time was prolonged compared to the reference mixture. Furthermore, based on the results of the SAI (Strength Activity Index) test, an acceptable level of strength development was demonstrated, confirming that WG and GBS possess the potential to replace cement while meeting the minimum strength requirements outlined in the specifications. Microstructure analyses revealed good adhesion between WGP, GGBS, and the cementitious binder. This research contributes to the development of eco-efficient binders that exhibit increased cement replacement ratios and qualities comparable to, or even superior to, traditional cement systems

Physical and mechanical properties of foamed Portland cement composite containing crumb rubber from worn tires

The management of worn tires is a concern in industrialized countries. The application of crumb rubber as lightweight aggregate in cement based materials is a green alternative for reusing this material. High replacements of natural sand by crumb rubber were studied and an air-entraining agent was employed to ensure a cellular structure in the cement-based composite. The obtained results from tests in fresh state reveal an improvement in workability. The tests conducted on hardened composite show promise for constructive applications where thermal and acoustic properties are required. The minimum requirement of mechanical strength for masonry units was achieved, since compressive strengths varied between 1 and 10 MPa. Finally, potential applications as a construction material have been highlightedEiras Fernández, JN.; Segovia Rueda, F.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Bonilla Salvador, MM.; Paya Bernabeu, JJ. (2014). Physical and mechanical properties of foamed Portland cement composite containing crumb rubber from worn tires. Materials and Design. 59:550-557. doi:10.1016/j.matdes.2014.03.021S5505575

Bamboo reinforced concrete: a critical review

© 2018, The Author(s). The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or round strips) has often been proposed as an alternative to relatively expensive reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost—bamboo is readily available in many tropical and sub-tropical locations, whereas steel reinforcement is relatively more expensive—and more recently, the drive to find more sustainable alternatives in the construction industry. This review addresses such ‘bamboo-reinforced concrete’ and assesses its structural and environmental performance as an alternative to steel reinforced concrete. A prototype three bay portal frame, that would not be uncommon in regions of the world where bamboo-reinforced concrete may be considered, is used to illustrate bamboo reinforced concrete design and as a basis for a life cycle assessment of the same. The authors conclude that, although bamboo is a material with extraordinary mechanical properties, its use in bamboo-reinforced concrete is an ill-considered concept, having significant durability, strength and stiffness issues, and does not meet the environmentally friendly credentials often attributed to it