References of "Michel, Frédéric"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailDurability of mortar and concretes containing slag with low hydraulic activity
Hadj Sadok, Ahmed; Kenaï, Saïd; Courard, Luc ULg et al

in Cement & Concrete Composites (2012), 34(5), 671677

Granulated blast furnace slag has been widely used as a partial substitute for Portland cement in many applications because of advantages which include cost reduction, reduction in heat evolution and ... [more ▼]

Granulated blast furnace slag has been widely used as a partial substitute for Portland cement in many applications because of advantages which include cost reduction, reduction in heat evolution and improvement of durability properties. However, the effectiveness of slag depends on its hydraulic reactivity. In this paper, the results of an experimental study on the effect of slag with low hydraulicity on the mechanical and durability properties of concrete and the performance of mortar under sulfate attack are discussed. Special attention is given to gas permeability and water absorption of slag concrete. The durability of slag concrete is improved at long term at low Water/Binder ratio. Sulfate resistance of mortar is improved by slag replacement up to 30%. [less ▲]

Detailed reference viewed: 167 (4 ULg)
Full Text
Peer Reviewed
See detailNatural limestone fillers : physical and chemical properties with regard to cement based materials performances
Michel, Frédéric ULg; Courard, Luc ULg

in Durability of concrete 2012 (2012)

Natural limestone fillers are available on the market and supplied by limestone aggregates industry but also ornamental stone suppliers. The use of limestone fillers in cement based concrete requires a ... [more ▼]

Natural limestone fillers are available on the market and supplied by limestone aggregates industry but also ornamental stone suppliers. The use of limestone fillers in cement based concrete requires a thorough characterization of the materials. Physical and chemical properties will influence behaviour of the fresh and hardened concrete. Impurities may affect cement hydration process, delay the setting time and decrease the compressive strength. Six types of limestone fillers, in the form of finely ground limestone powders, have been collected in Belgium (more precisely in Wallonia Region). They differ from each other through their physical properties (Blaine fineness, particle size distribution, water demand) but also chemical and mineralogical properties (presence of impurities such as sulphate, clay, quartz and dolomite). Special attention has been focused on clay content and type influences; limestone fillers have been artificially polluted with clays in order to investigate their behaviour in cement based mortars. The effect of the nature and the substitution rate of the fillers on the properties of mortars are investigated. Relationships between physico-chemical properties of the fillers and the properties of mortars clearly indicate a harder influence of the limestone composition on the fresh than the hardened properties. [less ▲]

Detailed reference viewed: 506 (7 ULg)
Full Text
Peer Reviewed
See detailCharacterization of fine aggregates in concrete by different experimental approaches
He, Huan ULg; Courard, Luc ULg; Pirard, Eric ULg et al

in Proceedings 13 Int. Congress for Stereology (2011, October)

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties ... [more ▼]

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties of concrete. On another hand, physical characteristics of aggregate are primarily assumed to be relevant to granular behavior of aggregate. Therefore, characterization of aggregate is of high relevance to concrete studies. In this study, different types of fine aggregate used in concrete, namely river sand and crushed limestone, are selected for morphological characterization. Traditional sieve analysis and laser diffraction method are employed for separation and size analysis of specimens. Different types of fine aggregate samples with comparable size ranges are then analyzed by two advanced dry (static) and wet (dynamic) image analysers. These new analysers are especially suitable for characterization of fine particles, which is difficult by traditional image analysis equipments. Size and shape characteristics of different fine aggregates will be revealed by different experimental methods. The results on different parameters for shape characterization will be compared and discussed. [less ▲]

Detailed reference viewed: 105 (16 ULg)
Full Text
See detailCharacterization of fine aggregates in concrete by different experimental approaches
He, Huan; Courard, Luc ULg; Pirard, Eric ULg et al

in Proceedings 13 Int. Congress for Stereology (2011, October)

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties ... [more ▼]

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties of concrete. On another hand, physical characteristics of aggregate are primarily assumed to be relevant to granular behavior of aggregate. Therefore, characterization of aggregate is of high relevance to concrete studies. In this study, different types of fine aggregate used in concrete, namely river sand and crushed limestone, are selected for morphological characterization. Traditional sieve analysis and laser diffraction method are employed for separation and size analysis of specimens. Different types of fine aggregate samples with comparable size ranges are then analyzed by two advanced dry (static) and wet (dynamic) image analysers. These new analysers are especially suitable for characterization of fine particles, which is difficult by traditional image analysis equipments. Size and shape characteristics of different fine aggregates will be revealed by different experimental methods. The results on different parameters for shape characterization will be compared and discussed [less ▲]

Detailed reference viewed: 87 (3 ULg)
Full Text
Peer Reviewed
See detailSurfology Based Concrete Repair Engineering
Courard, Luc ULg; Michel, Frédéric ULg; Garbacz, Andrzej et al

in Polymers in sustainable construction (2011)

Research projects performed at the University of Liege and the Warsaw University of Technology have pointed out the importance of taking care about surfology of materials: if durability also means ... [more ▼]

Research projects performed at the University of Liege and the Warsaw University of Technology have pointed out the importance of taking care about surfology of materials: if durability also means sustainability, we may then consider that optimization in material selection is essential for repair efficient. Surfology contributes to understand what will make the contact effective or not, and allow interactions of variable intensities between the materials. Different scales of observation – micro to macro - are needed to exactly represent what happens when materials are put into contact. [less ▲]

Detailed reference viewed: 54 (2 ULg)
Full Text
Peer Reviewed
See detailMineralization of bio-based materials: effect on cement-based mix properties
Courard, Luc ULg; Darimont, Anne ULg; Louis, Arnaud ULg et al

in Bulletin of the Polytechnic Institute of Jassy, Construction. Architecture Section (2011), LIV(LVIII),

The lightweight concrete with bio-based products knows an interesting development in the construction field, especially as thermal insulation panels for walls in buildings. Before identifying and ... [more ▼]

The lightweight concrete with bio-based products knows an interesting development in the construction field, especially as thermal insulation panels for walls in buildings. Before identifying and quantifying the basic physical characteristics of concrete made from wood, miscanthus, hemp or bamboo (acoustic and thermal properties in particular), it is necessary to optimize the composition of the product. It is clear that the final product is not unique and a compromise has to be found between insulation and mechanical properties. The long term stability as well as the reinforcement may be obtained by means of a mineralization process of the natural product: a preparation with a lime and/or cement-based material is necessary to reinforce the cohesion of the bio-based product. Optical and SEM analysis helped to clearly understand the interactions between the bio-based fibrous material and the cementitious materials, the quality of the bond and their effects on the properties of the cement-based concrete products. [less ▲]

Detailed reference viewed: 181 (18 ULg)
Full Text
Peer Reviewed
See detailSaturation level of the superficial zone of concrete and adhesion of repair systems
Courard, Luc ULg; Lenaers, Jean-François; Michel, Frédéric ULg et al

in Construction & Building Materials (2011), 25((5)), 2488-2494

Appropriate surface saturation level is essential for the durability of the repaired structure. The repair material is often blamed for ‘‘not sticking’’, although the general source of the trouble lies ... [more ▼]

Appropriate surface saturation level is essential for the durability of the repaired structure. The repair material is often blamed for ‘‘not sticking’’, although the general source of the trouble lies with the substrate surface conditioning. An extensive research project has been undertaken to develop specifications and performance criteria for surface preparation of concrete substrates. A field test was developed to evaluate the optimum moisture conditioning of the substrate concrete prior to application of repair material; this has been calibrated and compared with destructive and non-destructive on three types of concrete and two types of surface preparation. In order to evaluate different saturation levels, concrete samples have been stored in more than 12 modes of conservation. Finally, repair mortars have been applied on concrete substrates and adhesion was measured for different concrete surface saturation levels. Initial Surface Absorption Test (ISAT) can be used as an attractive quantitative test to evaluate saturation level of concrete substrate. Moreover, it is clearly shown that saturation levels higher than 50% and lower than 90% are requested for promoting adhesion of PCC mortars. [less ▲]

Detailed reference viewed: 99 (13 ULg)
Full Text
Peer Reviewed
See detailInfluence of clay in limestone fillers for self compacting cement based composites
Courard, Luc ULg; Michel, Frédéric ULg; Piérard, Julie

in Construction & Building Materials (2011), 25

High workability together with a good resistance to segregation is needed for cement based composites, specifically fresh Self-Compacting Mortars (SCM); in this prospect, the amount of coarse materials ... [more ▼]

High workability together with a good resistance to segregation is needed for cement based composites, specifically fresh Self-Compacting Mortars (SCM); in this prospect, the amount of coarse materials has to be reduced and replaced by fine material. Several limestone fillers are here compared and analysed. These by-products are issued from different industrial sectors, such as the aggregate and lime production industry (quarrying operations) and the ornamental stones industry (sawing operations). Particular attention has been paid to clay content, as consistency of fresh mortars was varying, while other physical characteristics like granulometry remained the same. Relationship between the physico-chemical properties of the fillers and the properties of fresh and hardened mortars are brought forward. Even if it may affect fresh properties of mortars, results clearly show that clay type and content has minor influence than limestone filler itself. [less ▲]

Detailed reference viewed: 102 (12 ULg)
Full Text
Peer Reviewed
See detailThe evaluation of the surface free energy of liquids and solids in concrete technology
Courard, Luc ULg; Michel, Frédéric ULg; Martin, Marie

in Construction & Building Materials (2011), 25

This paper presents initial results from an extensive study on the calculation of the surface free energy of mineral materials. The usefulness of such evaluation is demonstrated through the technological ... [more ▼]

This paper presents initial results from an extensive study on the calculation of the surface free energy of mineral materials. The usefulness of such evaluation is demonstrated through the technological operation of casting and moulding concrete. Surface interactions will firstly act on the dispersion of particles inside the concrete mix and the viscosity of the fresh material; the specific effect of superplasticizers and Modifying Viscosity Agent is presented through the determination of surface free energy properties. The second analysis is dealing with the interactions between mineral and vegetal oils applied on the wooden or steel formwork and fresh concrete. The evaluation of contact angle and interfacial forces help to efficiently select the most appropriate material. [less ▲]

Detailed reference viewed: 128 (7 ULg)
Full Text
See detailRecherche dans le domaine du béton à l'Université de Liège (2009-2010)
Dotreppe, Jean-Claude ULg; Franssen, Jean-Marc ULg; Somja, H. et al

Scientific conference (2010, October 21)

Detailed reference viewed: 145 (18 ULg)
Full Text
See detailInfluence of particle flatness and elongation on size distributions obtained from laser diffraction, static and dynamic image analysis.
Califice, Arnaud ULg; Michel, Frédéric ULg; Dislaire, Godefroid et al

in World Congress on Particle Technology (2010, April)

Detailed reference viewed: 62 (18 ULg)
Full Text
See detailLa formation: un outil indispensable pour l'ingénieur
Courard, Luc ULg; Michel, Frédéric ULg

Article for general public (2010)

Detailed reference viewed: 41 (6 ULg)
Full Text
Peer Reviewed
See detailSurfology: concrete substrate evaluation prior to repair
Courard, Luc ULg; Michel, Frédéric ULg; Schwall, Damien ULg et al

in Mammoli, A.; Brebbia, C. A. (Eds.) Materials Characterization: computational methods and experiments IV (2009)

The study of adhesion of repair materials on concrete structures implies a good knowledge of the influence of concrete surface treatment. The effects of surface preparation technique are rarely clearly ... [more ▼]

The study of adhesion of repair materials on concrete structures implies a good knowledge of the influence of concrete surface treatment. The effects of surface preparation technique are rarely clearly described and parameterised: it is consequently difficult to point out the real influence of roughness on adhesion results. A large research project has been realized with regards to the influence of concrete substrate strength and preparation technique efficiency. The surface roughness of concrete has been quantified by means of the projection “Moiré” technique, which is an interferometrical measurement method. Comparison between polished, scrabbled and hydro-jetted surfaces evaluation is presented. [less ▲]

Detailed reference viewed: 143 (33 ULg)
Full Text
See detailLe béton apparent: influence de l'état du moule sur l'aspect des surfaces
Martin, Marie; Migeotte, Nathalie; Goffinet, Cécile et al

in Benboudjema, Farid (Ed.) Compte-rendu des Journées Scientifiques du (RF)2B (2009)

L’aspect d’un parement en béton (teinte et bullage) dépend entre autres de la surface de coffrage utilisée. L’influence du nombre de réutilisations des coffrages sur la teinte et le bullage de surface a ... [more ▼]

L’aspect d’un parement en béton (teinte et bullage) dépend entre autres de la surface de coffrage utilisée. L’influence du nombre de réutilisations des coffrages sur la teinte et le bullage de surface a été étudiée. Deux séries de moules en bois contreplaqué et OBS ont été usés afin de simuler de 1 à 118 réutilisations pour le contreplaqué et de 2 à 51 réutilisations pour le bois OSB. Les moules ont ensuite été utilisés pour couler des cubes de béton. La première série a été coulée en utilisant une huile végétale et la deuxième une huile minérale. La teinte et le bullage en surface des bétons coulés ont été mesurés et étudiés au travers d’une étude statistique afin de déterminer l’influence de la réutilisation des coffrages sur l’aspect des parements. [less ▲]

Detailed reference viewed: 75 (2 ULg)
Full Text
Peer Reviewed
See detailUse of concrete road recycled aggregates for Roller Compacted Concrete
Courard, Luc ULg; Michel, Frédéric ULg; Delhez, Pascal

in Construction & Building Materials (2009), 24((3)), 390-395

Construction waste management is a quite important economical and environmental deal for our societies. More than 2 million tons demolition and construction wastes are annually produced only in Wallonia ... [more ▼]

Construction waste management is a quite important economical and environmental deal for our societies. More than 2 million tons demolition and construction wastes are annually produced only in Wallonia, Southern Region of Belgium; recycling has clearly to be promoted. Roller Compacted Concrete (RCC) is a special dry concrete made of aggregates, water and low quantity of cement, laid down and compacted like a soil, for the construction of massive structures like dams or large horizontal surfaces like road foundations. The topic of this research is the replacement of natural aggregates by concrete road recycled aggregates in the mix design of concrete. Characteristics of aggregates are of prime importance for the quality of the concrete: Los Angeles, water absorption and specific gravity. It has been observed that RCC with natural and concrete road recycled aggregates are similar for solid compactness, while no major influence of cement content – when around 200 kg - may be detected. However, compressive strength is higher for RCC with natural aggregates. This study clearly shows the opportunity of using concrete road recycled aggregates for RCC in basements. [less ▲]

Detailed reference viewed: 99 (11 ULg)
Full Text
See detailRecherches menées à l'Université de Liège dans le domaine du béton en 2008-2009
Dotreppe, Jean-Claude ULg; Franssen, Jean-Marc ULg; Somja, Hugues et al

Conference given outside the academic context (2009)

Composite steel-concrete columns made of CFSHS filled with self compacting concrete under ambaint temperature and in the fire situation. Design equation for the buckling of high strength concrete columns ... [more ▼]

Composite steel-concrete columns made of CFSHS filled with self compacting concrete under ambaint temperature and in the fire situation. Design equation for the buckling of high strength concrete columns subkected to compression and bending. Improvement of the textural quality of concrete with hydraulic binders. Influence of the reutilisation of OSB panels shuttering on the colour and texture of concrete surfaces. Non destructive methods for the detection of delamination in the decks of concrete bridges [less ▲]

Detailed reference viewed: 174 (25 ULg)
Full Text
Peer Reviewed
See detailApplication du concept de performance équivalente aux bétons additionnés de fillers calcaires
Michel, Frédéric ULg; Piérard, Julie; Courard, Luc ULg

in Annales du Bâtiment et des Travaux Publics (2008), 3

The European standard EN 206-1 integrates the concept of the k-coefficient that allows to take into account the addition of pozzolanic and hydraulic fine materials in order to respect the requirements ... [more ▼]

The European standard EN 206-1 integrates the concept of the k-coefficient that allows to take into account the addition of pozzolanic and hydraulic fine materials in order to respect the requirements concerning the formulation of concrete for the chosen environment. Some national application documents extend this concept to other types of mineral additives such as limestone fillers. In Belgium this principle is not applied yet. Within the scope of the current study, limestone fillers coming from different activity sectors in the Walloon Region (production of aggregates, lime or ornamental stones) were selected. Their influence on the consistency of concrete, its mechanical properties and its long-term behaviour (water-porosity, air permeability and carbonation resistance) was evaluated. [less ▲]

Detailed reference viewed: 122 (14 ULg)
Full Text
Peer Reviewed
See detailInfluence of physico-chemical characteristics of limestone fillers on fresch and hardened mortar performances
Michel, Frédéric ULg; Piérard, Julie; Courard, Luc ULg et al

in De Schutter, G.; Boel, V. (Eds.) Self-Compacting Concrete SCC 2007 (2007, September)

In order to meet the specific requirements for fresh Self-Compacting Concrete (SCC), i.e. a high workability together with a good resistance to segregation, the amount of coarse aggregates has to be ... [more ▼]

In order to meet the specific requirements for fresh Self-Compacting Concrete (SCC), i.e. a high workability together with a good resistance to segregation, the amount of coarse aggregates has to be reduced and replaced by fine material. Since cement is quite expensive and can develop a high heat of hydration with possible problems for thermal cracks in massive concrete, mineral fillers are usually used. In Belgium, local available materials are limestone fillers; they are very well-adapted for the optimisation of particle packing and flow behaviour of cementitious paste in SCC mixes. These by-products are issued from different sectors, such as the aggregate and lime production industry (quarrying operations) and the ornamental stones industry (sawing operations). The suitability of these fillers for use in SCC or conventional concrete production was investigated. This paper reports the effect of the nature and the substitution rate of the fillers on the properties of mortars. Some relationship between the physico-chemical properties of the fillers and the properties of mortars were brought forward. [less ▲]

Detailed reference viewed: 143 (9 ULg)
Full Text
See detailSIZE DISTRIBUTION OF METALLIC POWDERS : A COMPARISON OF DIGITAL IMAGING AND LASER DIFFRACTION
Gregoire, Max; Michel, Frédéric ULg; Campana, Florent et al

Poster (2007)

Automated image analysis of particles under controlled orientation (SIA) is becoming a challenging technique for laser diffraction (LD) in the field of sizing metallic particles above 5 μm. Thanks to ... [more ▼]

Automated image analysis of particles under controlled orientation (SIA) is becoming a challenging technique for laser diffraction (LD) in the field of sizing metallic particles above 5 μm. Thanks to optimal particle dispersion and fully automated microscopic imaging, it is now possible to gather individual measurements on thousands of particles within a minute. The aim of this paper is to compare results obtained with both image analysis and laser diffraction from a selection of powders (figure 1) in the range between 5 μm and 250 μm. [less ▲]

Detailed reference viewed: 46 (1 ULg)