Mouhamadou AMAR

Dans: NOMAD 2022 - 4e conférence internationale francophone Nouveaux Matériaux et Durabilité, IMT Mines Al`es and LMGC and LIFAM Montpellier, France, 2022, (ACTI).

Liens

2022Article de journal ER2

Auteurs : Kleib, Joelle; Amar, Mouhamadou; Aouad, Georges; Bourbon, Xavier; Benzerzour, Mahfoud; Abriak, Nor-Edine

The Use of Callovo-Oxfordian Argillite as a Raw Material for Portland Cement Clinker Production

Dans: Buildings, vol. 12, no. 9, p. 1421, 2022, (ACL).

Liens

2022Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Abriak, Nor-Edine

Designing Efficient Flash-Calcined Sediment-Based Ecobinders

Dans: Materials, vol. 15, no. 20, p. 7107, 2022, (ACL).

Liens

2022Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Zentar, Rachid; Abriak, Nor-Edine

Prediction of the Compressive Strength of Waste-Based Concretes Using Artificial Neural Network

Dans: Materials, vol. 15, no. 20, p. 7045, 2022, (ACL).

Liens

2022Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Zentar, R.; Abriak, Nor-Edine

Prediction of the Compressive Strength of Waste-Based Concretes Using Artificial Neural Network

Dans: Materials, vol. 15, no. 20, p. 7045, 2022.

Liens

2021Article de journal ER2

Auteurs : Chu, Duc Chinh; Kleib, Joelle; Amar, Mouhamadou; Benzerzour, Mahfoud; Abriak, Nor-Edine

Determination of the degree of hydration of Portland cement using three different approaches: Scanning electron microscopy (SEM-BSE) and Thermogravimetric analysis (TGA)

Dans: Case Studies in Construction Materials, vol. 15, p. e00754, 2021, (ACL).

Liens

2021Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Kleib, Joelle; Abriak, Nor-Edine

From dredged sediment to supplementary cementitious material: characterization, treatment, and reuse

Dans: International Journal of Sediment Research, vol. 36, no. 1, p. 92-109, 2021, (ACL).

Liens

2020Article de journal ER2

Auteurs : Wang, Dongxing; Wang, Hongwei; Larsson, Stefan; Benzerzour, Mahfoud; Maherzi, Walid; Amar, Mouhamadou

Effect of basalt fiber inclusion on the mechanical properties and microstructure of cement-solidified kaolinite

Dans: Construction and Building Materials, vol. 241, p. 118085, 2020, ISSN: 0950-0618, (ACL).

Résumé | Liens

@article{WANG2020118085,

title = {Effect of basalt fiber inclusion on the mechanical properties and microstructure of cement-solidified kaolinite},

author = {Dongxing Wang and Hongwei Wang and Stefan Larsson and Mahfoud Benzerzour and Walid Maherzi and Mouhamadou Amar},

url = {http://www.sciencedirect.com/science/article/pii/S0950061820300908},

doi = {https://doi.org/10.1016/j.conbuildmat.2020.118085},

issn = {0950-0618},

year  = {2020},

date = {2020-01-01},

journal = {Construction and Building Materials},

volume = {241},

pages = {118085},

abstract = {The polypropylene fibers, which are currently attracting enormous attention in various geotechnical applications, carry a risk of aging under an integrated effect of heat, oxygen, light and other environmental factors, causing potentially infrastructure failure. An eco-friendly and biologically inactive material – basalt fiber, which has excellent natural resistance to aging and can eliminate aging-associated disasters, deserves more attention in geotechnical field. However, quite few studies are available on the beneficial reuse of basalt fibers to improve the engineering performance of soils. Therefore, this study aims to incorporate the sustainable basalt fiber and clarify how its inclusion impacts the mechanical properties and microstructure of cemented kaolinite. The experimental programs are comprised of three types of tests, i.e. two to examine the compressive strength and triaxial shear behavior and one to evaluate the microstructure properties. The results indicate that the basalt fiber reinforcement plays an essential role in enhancing the compressive strength and peak deviatoric stress of cemented and uncemented kaolinite. The inclusion of basalt fibers improves the ductility and weakens the brittleness of cemented kaolinite. The compressive strength increases with basalt fiber content and curing time, and reaches the peak at the fiber content of 0.2%, followed by a reduction due to the formation of weak zone at higher fiber content. The peak deviatoric stress is elevated until reaching the maximum at the basalt fiber content of 0.4%, after which further addition of basalt fiber tends to reduce its reinforcing effect. The peak deviatoric stress increases as the basalt fiber length is shortened and the confining pressure is raised. The strength gain of cement-basalt fiber inclusion is much more than the sum of strength increase induced by them individually. The combination of basalt fiber and cement has the virtues of both cement-stabilized and basalt fiber-reinforced kaolinite. The SEM analysis reveals that the mechanical interaction in the form of interface bonding and friction between kaolinite particle, cement hydration product and basalt fiber is the dominant mechanism controlling the reinforcement-cementation benefits. The bridging effect (reinforcement) of basalt fibers and binding effect (cementation) of hydration products make a major contribution to the formation of stable and interconnected microstructure, which results in an evident improvement in the mechanical behaviour of cemented kaolinite. The combination of basalt fiber and cement stabilization would be an innovative and effective method for geotechnical engineering works such as soft ground improvement.},

note = {ACL},

keywords = {ER2},

pubstate = {published},

tppubtype = {article}

}

Fermer

The polypropylene fibers, which are currently attracting enormous attention in various geotechnical applications, carry a risk of aging under an integrated effect of heat, oxygen, light and other environmental factors, causing potentially infrastructure failure. An eco-friendly and biologically inactive material – basalt fiber, which has excellent natural resistance to aging and can eliminate aging-associated disasters, deserves more attention in geotechnical field. However, quite few studies are available on the beneficial reuse of basalt fibers to improve the engineering performance of soils. Therefore, this study aims to incorporate the sustainable basalt fiber and clarify how its inclusion impacts the mechanical properties and microstructure of cemented kaolinite. The experimental programs are comprised of three types of tests, i.e. two to examine the compressive strength and triaxial shear behavior and one to evaluate the microstructure properties. The results indicate that the basalt fiber reinforcement plays an essential role in enhancing the compressive strength and peak deviatoric stress of cemented and uncemented kaolinite. The inclusion of basalt fibers improves the ductility and weakens the brittleness of cemented kaolinite. The compressive strength increases with basalt fiber content and curing time, and reaches the peak at the fiber content of 0.2%, followed by a reduction due to the formation of weak zone at higher fiber content. The peak deviatoric stress is elevated until reaching the maximum at the basalt fiber content of 0.4%, after which further addition of basalt fiber tends to reduce its reinforcing effect. The peak deviatoric stress increases as the basalt fiber length is shortened and the confining pressure is raised. The strength gain of cement-basalt fiber inclusion is much more than the sum of strength increase induced by them individually. The combination of basalt fiber and cement has the virtues of both cement-stabilized and basalt fiber-reinforced kaolinite. The SEM analysis reveals that the mechanical interaction in the form of interface bonding and friction between kaolinite particle, cement hydration product and basalt fiber is the dominant mechanism controlling the reinforcement-cementation benefits. The bridging effect (reinforcement) of basalt fibers and binding effect (cementation) of hydration products make a major contribution to the formation of stable and interconnected microstructure, which results in an evident improvement in the mechanical behaviour of cemented kaolinite. The combination of basalt fiber and cement stabilization would be an innovative and effective method for geotechnical engineering works such as soft ground improvement.

Fermer

2020Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Kleib, Joelle; Abriak, Nor-Edine

From dredged sediment to supplementary cementitious material: Characterization, treatment, and reuse

Dans: International Journal of Sediment Research, 2020, ISSN: 1001-6279.

Résumé | Liens

2018Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Abriak, Nor-Edine; Safhi, Amine El Mahdi

Durability of a cementitious matrix based on treated sediments

Dans: Case Studies in Construction Materials, vol. 8, p. 258 - 276, 2018, ISSN: 2214-5095, (ACL).

Résumé | Liens

@article{AMAR2018258,

title = {Durability of a cementitious matrix based on treated sediments},

author = {Mouhamadou Amar and Mahfoud Benzerzour and Nor-Edine Abriak and Amine El Mahdi Safhi},

url = {http://www.sciencedirect.com/science/article/pii/S221450951730164X},

doi = {https://doi.org/10.1016/j.cscm.2018.01.007},

issn = {2214-5095},

year  = {2018},

date = {2018-01-01},

journal = {Case Studies in Construction Materials},

volume = {8},

pages = {258 - 276},

abstract = {Significant volumes of sediment are annually dredged in France and all over the world and these materials may in fact be used beneficially as supplementary cementitious material. This paper studies the durability of a new cement matrix based on dredged marine sediment from the Dunkirk-Harbour (northern France). Several techniques are used to characterise the raw sediment, such as physical properties, chemical analyses and mineralogy. X-Ray Diffraction (XRD) analysis revealed quartz, calcite and kaolinite to be the main mineral phases. In order to eliminate organic matter and activate some of those minerals, the sediment is calcined at a temperature of 850 °C for 1 h. Moreover, four blended mortars were formulated by mixing a portland cement (CEM I 52,5 N) and the calcined sediment as a partial cement substitute (0%, 10%, 20% and 30%). Reference mortars, based on the blended cement, were then prepared. This re-use cannot be substantiated or efficient without a durability study. For this purpose, the following tests were conducted on those mortars: mercury porosity, accessible water porosity, chloride permeability, freezing and thawing, external sulphate attack, alkali aggregates reaction, compressive and bending strength tests. The results of most of those tests evidenced the fact that the mortar that contains 10% of the treated sediment is as efficient and durable as the reference mortar itself. This infers that the presence of these calcined sediments improves the general behaviour of mortar.},

note = {ACL},

keywords = {ER2},

pubstate = {published},

tppubtype = {article}

}

Fermer

2018Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Abriak, Nor-Edine

Towards the establishment of formulation laws for sediment-based mortars

Dans: Journal of Building Engineering, vol. 16, p. 106 - 117, 2018, ISSN: 2352-7102, (ACL).

Résumé | Liens

2018Article de journal ER2

Auteurs : Benzerzour, Mahfoud; Maherzi, Walid; Amar, Mouhamadou; Abriak, Nor-Edine; Damidot, D

Formulation of mortars based on thermally treated sediments

Dans: Journal of Material Cycles and Waste Management, vol. 20, no. 1, p. 592-603, 2018, (ACL).

Liens

2017Article de journal ER2

Auteurs : Benzerzour, Mahfoud; Amar, Mouhamadou; Abriak, Nor-Edine

New experimental approach of the reuse of dredged sediments in a cement matrix by physical and heat treatment

Dans: Construction and Building Materials, vol. 140, p. 432 - 444, 2017, ISSN: 0950-0618, (ACL).

Résumé | Liens

@article{BENZERZOUR2017432,

title = {New experimental approach of the reuse of dredged sediments in a cement matrix by physical and heat treatment},

author = {Mahfoud Benzerzour and Mouhamadou Amar and Nor-Edine Abriak},

url = {http://www.sciencedirect.com/science/article/pii/S0950061817303446},

doi = {https://doi.org/10.1016/j.conbuildmat.2017.02.142},

issn = {0950-0618},

year  = {2017},

date = {2017-01-01},

journal = {Construction and Building Materials},

volume = {140},

pages = {432 - 444},

abstract = {Dans cette étude, les sédiments sont utilisés comme matière première secondaire en substitution du ciment moyennant un traitement préalable. Le traitement envisagé est un traitement physique par broyage et séparation afin d’obtenir différentes fractions, par voie sèche (1mm, 250μm, 120μm) et par voie humide (250μm et 120μm). Ils sont par la suite traités thermiquement à des températures de 650°C, 750°C et 850°C pendant 1 heure et 3 heures, dans le but de les activer chimiquement par décarbonatation ou activation pouzzolanique du matériau. Différents essais de caractérisation ont été effectués. La détermination des caractéristiques physiques et chimiques principales est obtenue grâce à des essais de: granulométrie, masse volumique spécifique, la surface spécifique BET, estimation temps de début de prise ainsi que la chaleur d’hydratation par calorimétrie Langavant. Les essais chimiques menés sont entre autres: l’analyse ATG, la diffractométrie au rayon X (DRX) et la fluorescence X (FX), qui ont permis de quantifier les fractions, phases et éléments chimiques présents. Les essais à la compression ont été effectués conformément à la NF EN 196-1 à des échéances de 7 jours – 14 jours - 28 jours et 60 jours sur l’ensemble des mortiers formulés: les mortiers à base 100% de ciment CEM I 52.5N, sur ceux substitués à des taux de 8% et 15% par le sédiment traité. Ceux-ci ont permis de relever un apport dû à l’activité confirmée par des essais de calorimétrie ou du point de vue physique à une possible nucléation hétérogène autour des grains de sédiment. 

In this study, a sediment was used as a secondary raw material in cement substitution with prior treatment. The treatment adopted is a physical treatment involving grinding and separation to obtain different fractions, using a dry method (1mm, 250µm, 120µm) and washing method (250µm and 120µm). They were subsequently heat treated at temperatures of 650°C, 750°C and 850°C for 1h and 3h, in order to enable chemical activation by decarbonation or by pozzolanic activation of the material. Different characterization tests were performed. The determination of main physical and chemical characteristics was obtained through multiple techniques: particle size distribution, specific density, the BET surface area, the initial setting time and hydration heat calorimetry Langavant. The chemical tests include: TGA analysis, X-ray diffractometry (XRD) and X-ray fluorescence (XRF) which were used to quantify the fractions, phases and chemical elements present. Compression tests were performed conforming NF EN 196-1 French standard, over terms of 7days – 14days – 28days and 60days on all formulated mortars: reference mortar based on 100% CEM I 52.5N binder and cement substituted mortars with 8% and 15% by treated sediment. This clearly evidenced contribution due to chemical activity which was confirmed by calorimetry monitoring and strength investigation.},

note = {ACL},

keywords = {ER2},

pubstate = {published},

tppubtype = {article}

}

Fermer

Dans cette étude, les sédiments sont utilisés comme matière première secondaire en substitution du ciment moyennant un traitement préalable. Le traitement envisagé est un traitement physique par broyage et séparation afin d’obtenir différentes fractions, par voie sèche (1mm, 250μm, 120μm) et par voie humide (250μm et 120μm). Ils sont par la suite traités thermiquement à des températures de 650°C, 750°C et 850°C pendant 1 heure et 3 heures, dans le but de les activer chimiquement par décarbonatation ou activation pouzzolanique du matériau. Différents essais de caractérisation ont été effectués. La détermination des caractéristiques physiques et chimiques principales est obtenue grâce à des essais de: granulométrie, masse volumique spécifique, la surface spécifique BET, estimation temps de début de prise ainsi que la chaleur d’hydratation par calorimétrie Langavant. Les essais chimiques menés sont entre autres: l’analyse ATG, la diffractométrie au rayon X (DRX) et la fluorescence X (FX), qui ont permis de quantifier les fractions, phases et éléments chimiques présents. Les essais à la compression ont été effectués conformément à la NF EN 196-1 à des échéances de 7 jours – 14 jours - 28 jours et 60 jours sur l’ensemble des mortiers formulés: les mortiers à base 100% de ciment CEM I 52.5N, sur ceux substitués à des taux de 8% et 15% par le sédiment traité. Ceux-ci ont permis de relever un apport dû à l’activité confirmée par des essais de calorimétrie ou du point de vue physique à une possible nucléation hétérogène autour des grains de sédiment.
In this study, a sediment was used as a secondary raw material in cement substitution with prior treatment. The treatment adopted is a physical treatment involving grinding and separation to obtain different fractions, using a dry method (1mm, 250µm, 120µm) and washing method (250µm and 120µm). They were subsequently heat treated at temperatures of 650°C, 750°C and 850°C for 1h and 3h, in order to enable chemical activation by decarbonation or by pozzolanic activation of the material. Different characterization tests were performed. The determination of main physical and chemical characteristics was obtained through multiple techniques: particle size distribution, specific density, the BET surface area, the initial setting time and hydration heat calorimetry Langavant. The chemical tests include: TGA analysis, X-ray diffractometry (XRD) and X-ray fluorescence (XRF) which were used to quantify the fractions, phases and chemical elements present. Compression tests were performed conforming NF EN 196-1 French standard, over terms of 7days – 14days – 28days and 60days on all formulated mortars: reference mortar based on 100% CEM I 52.5N binder and cement substituted mortars with 8% and 15% by treated sediment. This clearly evidenced contribution due to chemical activity which was confirmed by calorimetry monitoring and strength investigation.

Fermer

2017Article de journal ER2

Auteurs : Amar, Mouhamadou; Benzerzour, Mahfoud; Abriak, Nor-Edine; Mamindy-Pajany, Yannick

Study of the pozzolanic activity of a dredged sediment from Dunkirk harbour

Dans: Powder Technology, vol. 320, p. 748 - 764, 2017, ISSN: 0032-5910, (ACL).

Résumé | Liens

@article{AMAR2017748,

title = {Study of the pozzolanic activity of a dredged sediment from Dunkirk harbour},

author = {Mouhamadou Amar and Mahfoud Benzerzour and Nor-Edine Abriak and Yannick Mamindy-Pajany},

url = {http://www.sciencedirect.com/science/article/pii/S0032591017305909},

doi = {https://doi.org/10.1016/j.powtec.2017.07.055},

issn = {0032-5910},

year  = {2017},

date = {2017-01-01},

journal = {Powder Technology},

volume = {320},

pages = {748 - 764},

abstract = {Les additions ou produits de substitution dans les matrices cimentaires sont généralement caractérisés par leur aptitude à réagir dans des conditions spécifiées. Cette caractéristique peut être appréciée au travers de la mesure de l’activité pouzzolanique. Dans cette étude, la pouzzolanicité d’une certaine catégorie de matériaux est étudiée. Pour cela, les essais de Frattini conforme à la norme NF EN 196-5, l’essai Chapelle accéléré, la mesure de la conductivité électrique et le calcul du coefficient d’activité mécanique sont mis en place. Les résultats indiquent que le sédiment brut provenant du Grand Port Maritime de Dunkerque présente une relative faible activité pouzzolanique quel que soit le test considéré. Cependant, l’étude de fractions calcinées par voie directe ou par calcination flash a montré que le sédiment présente, à l’issue de ces processus, une activité améliorée. L’étude comparée avec plusieurs additions courantes a permis de démontrer la bonne fiabilité des méthodes de Chapelle et l’indice d’activité mécanique pour une grande diversité d'additions minérales. Toutefois, au test de conductivité, une correction doit être appliquée du fait de la présence de sels dissous. Des coefficients d’activité mécanique χA=0.88 et χA=0.73 ont été déterminés respectivement pour le STFC (flash) et le STDC (calcination directe). En conséquence, les sédiments, moyennant un traitement adéquat peuvent être utilisés comme des additions minérales actives pour les matrices cimentaires. Admixtures or supplementary cementitious materials are generally characterised by their ability to react in specified conditions. This can be assumed through the pozzolanicity. In this study, the pozzolanic activity of a certain category of materials was investigated. For this purpose, the Frattini test conforming to NF EN 196-5 French standard, the accelerated Chapelle test, the measurement of the electrical conductivity and the calculation of mechanical activity coefficient were performed. The raw sediment from Dunkirk harbour presented a relatively low pozzolanic activity regardless of the test considered. However, the study of direct or flash calcined materials evidenced that sediment acquired at the end of these processes an improvement of pozzolanic activity. The comparative study conducted on several common admixtures also inferred that the Chapelle and mechanical activity index methods are quite appropriate and reliable. Nevertheless, in the conductivity test, a correction must be applied due to the presence of dissolved salts. A mechanical activity coefficient of χA=0.88 and χA=0.73 was determined for STFC (flash) and STDC (direct lab kiln) respectively. As a result, sediment, following an optimized treatment can be used as active mineral admixture in cementitious matrixes.},

note = {ACL},

keywords = {ER2},

pubstate = {published},

tppubtype = {article}

}

Fermer

Les additions ou produits de substitution dans les matrices cimentaires sont généralement caractérisés par leur aptitude à réagir dans des conditions spécifiées. Cette caractéristique peut être appréciée au travers de la mesure de l’activité pouzzolanique. Dans cette étude, la pouzzolanicité d’une certaine catégorie de matériaux est étudiée. Pour cela, les essais de Frattini conforme à la norme NF EN 196-5, l’essai Chapelle accéléré, la mesure de la conductivité électrique et le calcul du coefficient d’activité mécanique sont mis en place. Les résultats indiquent que le sédiment brut provenant du Grand Port Maritime de Dunkerque présente une relative faible activité pouzzolanique quel que soit le test considéré. Cependant, l’étude de fractions calcinées par voie directe ou par calcination flash a montré que le sédiment présente, à l’issue de ces processus, une activité améliorée. L’étude comparée avec plusieurs additions courantes a permis de démontrer la bonne fiabilité des méthodes de Chapelle et l’indice d’activité mécanique pour une grande diversité d'additions minérales. Toutefois, au test de conductivité, une correction doit être appliquée du fait de la présence de sels dissous. Des coefficients d’activité mécanique χA=0.88 et χA=0.73 ont été déterminés respectivement pour le STFC (flash) et le STDC (calcination directe). En conséquence, les sédiments, moyennant un traitement adéquat peuvent être utilisés comme des additions minérales actives pour les matrices cimentaires. Admixtures or supplementary cementitious materials are generally characterised by their ability to react in specified conditions. This can be assumed through the pozzolanicity. In this study, the pozzolanic activity of a certain category of materials was investigated. For this purpose, the Frattini test conforming to NF EN 196-5 French standard, the accelerated Chapelle test, the measurement of the electrical conductivity and the calculation of mechanical activity coefficient were performed. The raw sediment from Dunkirk harbour presented a relatively low pozzolanic activity regardless of the test considered. However, the study of direct or flash calcined materials evidenced that sediment acquired at the end of these processes an improvement of pozzolanic activity. The comparative study conducted on several common admixtures also inferred that the Chapelle and mechanical activity index methods are quite appropriate and reliable. Nevertheless, in the conductivity test, a correction must be applied due to the presence of dissolved salts. A mechanical activity coefficient of χA=0.88 and χA=0.73 was determined for STFC (flash) and STDC (direct lab kiln) respectively. As a result, sediment, following an optimized treatment can be used as active mineral admixture in cementitious matrixes.

Fermer

2017Thèse ER2

Auteurs : Amar, Mouhamadou

Traitement des sédiments de dragage pour une valorisation dans les matrices cimentaires

Lille 1, 2017, (TH).

Résumé

Membre