Tesi sul tema "Composites de ciment – Surfaces"
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Zhu, Xiaodong. "Étude à l'échelle nanométrique du nano-revêtement organique efficace sur la surface de la pâte de ciment dans un environnement agressif pour des matériaux de construction durables". Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDENGSYS/2023/2023ULILN035.pdf.
Improving the life-time of cement paste is a significant challenge in construction sector. Surface treatment approaches, such as surface coating, surface pore sealing, and surface impregnation, have been playing a significant role to improve the durability of cement-based structures especially in preventing surface deterioration and damage. Experimental investigations indicate that surface coating, acting as a physical barrier, is an effective way for enhancing the durability of materials by avoiding the penetration either of water or hazards substances. Due to the experimental observation limitations, there is an urgency need to deeper delve the atomic level to understand the mechanism behind the success hydrophobic behavior of cement surface modified with a nano-coating treatment.Therefore, this dissertation adopts a nano-scale level study to understand and control the nano-coating process to engineer an impermeable hydrophobic Calcium-Silicate-Hydrate (CSH) surface through nano-coating of epoxy and rubber films under aggressive environment. To this end, Molecular Dynamics (MD) simulations based on a combination potential of a general force field (CLAYFF) and the consistent-valence force field (CVFF) have been employed to represent the interatomic interactions between CSH and epoxy or rubber films. A developed realistic model has been used to represent the CSH nanostructure.The thesis is dedicated, first, to study deeply the hydrated surface properties of CSH paste in order to thoroughly understand the hydrophilic nature of the (001) CSH surface. Then, a fully investigation has been performed on the interfacial interaction and adhesion properties between epoxy resins nano-coating and CSH surface. For that, we use diglycidyl ether of bisphenol A (DGEBA) as epoxy monomer and m-phenylenediamine (MPD) as hardener. Thereafter, an in-depth analysis of a hydrophobic rubber nano-coating process onto CSH surface is explored. Four types of rubber are employed, as TPI (1,4-trans-Polyisoprene), CPI (1,4-cis-Polyisoprene), TPB (1,4-trans-Polybutadiene), and CPB (1,4-cis-Polybutadiene). Finally, the present work is devoted to analyze the interfacial deterioration process between epoxy/rubber nano-coating of CSH surfaces under aggressive environment, like a salty water (4 wt.% of NaCl).Results obtained indicate that epoxy and rubber coated CSH surface energy are drastically dropped to the range of 33.7 mJ/m2- 48.4 mJ/m2, which extremely reduces the hydrophilicity of the CSH surface. The averaged contact angle between water-nanodroplet and rubber coated CSH surface is found in range of 92.85° and 98.11°. The calculated interfacial adhesion between organic-coatings (epoxy and rubber) and CSH is in range of 49.42 mJ/m2 to 102.81 mJ/m2. Additionally, m-phenylenediamine (MPD) would highly improve the epoxy nano-coating efficiency. Regarding rubber nano-coating, it is found that coating process with TPI (1,4-trans-Polyisoprene) and CPB (1,4-cis-Polybutadiene) than CPI (1,4-cis-Polyisoprene) and TPB (1,4-trans-Polybutadiene) will enhance efficiently the impermeability of CSH paste. Under aggressive conditions, non-fully epoxy nano-coating is detached more distorted in 4 wt.% of NaCl solution due to the chlorine ions, which are responsible to attack the CSH surface. A continuous well-distributed rubber nano-coating is capable to make CSH impermeable under harsh environment leading to a promising future for sustainable cementitious materials.The doctoral thesis concludes the feasibility and reliability of nano-coating by rubber film to prevent the interfacial deterioration of CSH surfaces in aggressive environment and to improve the impermeability of nano-coated CSH surfaces for more durable cementitious materials
Munzer, Charlotte. "Etude de l'action d'un bioadjuvant aux substances extracellulaires sur la microstructure et les caractéristiques de surface de pâtes cimentaires pour des bétons plus éco-respectueux". Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD028/document.
The influence of the incorporation of a product organically sourced in cementitious materials (at fresh and hardened state) was studied. The presence of the bioproduct does not cause changes on mechanical strength and on cement past microstructure (TGA / DTA and XRD). Porous network characterization tests on mortar and cement paste showed an effect of bioproduct on the quality of skin samples. A protocol of realization and conservation of cement paste samples was developed in order to allow various tests on same surfaces for the microbiologists partners of the « extra cellular substances for concrete » project. The study of the evolution of the dynamic contact angle of a drop of water placed on cement pastes showed that the presence of the bioproduct favored at the expense of spreading the penetration of water within the material, modifying the tortuosity of the capillaries of the cementitious matrix. An analytical method of drop behaviour (contact angle versus diameter) was developed and validated with literature data. This original technique allowed an accurate determination of the angles of advance and retreat on porous substrates
Pham, Ngoc Phuong. "Rubberized cement-based composite as material for large surface applications : effect of the rubber-cementitious matrix bond". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30077.
Properties of improved strain capacity and high shrinkage cracking resistance make rubberized cement-based composites suitable for large surface applications such as cement-based pavements and thin bonded overlays. However, bond defect between rubber aggregates (RA) and cement matrix is well-known and detrimental to properties of rubberized cement-based materials. It is universally accepted a reduction in some mechanical properties of rubberized cement-based composites mainly due to low stiffness of RA. Nevertheless, their transfer properties could indeed be competitive with control mortar (without RA) if bond at rubber-cement matrix interface is improved. In order to enhance the interface, RA were firstly coated with styrene-butadiene copolymer and after complete densification of this copolymer on surface of RA, they were mixed with the pre-mixed cementitious mixture. Microstructural analysis using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDS), and X-Ray Diffraction (XRD) clarified that cement paste bonded firmly on copolymer-coated RA. Mechanical and transfer properties of this mortar were then compared to that of control mortar and two rubberized mortars in which one of them air-detraining admixture was added to produce rubberized mixture with the similar air content as the control mortar. Findings have demonstrated an enhanced rubber-cement matrix interface provided a significant improvement on transfer properties such as air permeability and water capillary absorption. However, a reduction in mechanical properties (compressive strength and modulus of elasticity) was still observed due to low stiffness of RA. Rubber coating appeared to limit the reduction in tensile strength and to result in a higher residual post-peak strength and fracture energy, demonstrating an improved material bridging effect made possible by the bond between RA and cement matrix. The bridging effect also contributed to improve resistance of rubberized composites to shrinkage cracking even under high restrained conditions. Based on above-mentioned characteristics, the study further investigated the durability of rubberized mortars under aggressive environments to observe the effects of RA incorporation and of an enhanced rubber-cement matrix interface. Regarding acetic acid attack, a low degraded depth and a reduction in loss of both mass and compressive strength of rubberized mortars, especially the one incorporating copolymer-coated RA, were observed compared to the ones of the control mortar. The coated rubberized mortar also behaves better in preventing sodium sulfate diffusion into the composite. The degradation of mortars under aggressive environments was also evaluated based on a damage variable, which was defined as a relative change in equivalent load-resisting area of mortar specimens between their original condition and at a given time when they were exposed to acid or sulfate solutions. From damage variable values, it can be concluded that coated rubberized mortar was more durable than the untreated one against aggressive environments. The durability of untreated and coated rubberized mortars under freeze-thaw cycles was also carried out and compared to that of control mortar. The rubberized cement- based composites were more resistant to freezing and thawing than the control one, especially in terms of dimensional expansion. The better performance can be attributed to high energy absorption of RA and to higher porosity, lower water capillary absorption and high strain capacity of rubberized mortars. Rubber coating, even reducing the permeability of rubberized cement-based composites, still remained high durability of their applications under frost environment
Mimoun, Mostefa. "Etude de matériaux composites argile-ciment-fibres". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37608074v.
Farha, M'hamed. "Conception de composites ciment-verre à porosité minimale". Lyon, INSA, 1990. http://www.theses.fr/1990ISAL0046.
[The glass fibre reinforced composites (GFRC) has been used since 1970 in order to reduce the shrinkage of the cementitious· matrix. First the sand/cement ratio was about 0,3 ; yet thanks to the development of the equipments it has been increased to reach l. Thus, the composites precasted as mentioned above are characterized by an important opened porosity. It increases their permeability. On the one hand and leaves their internal structure open to humidity and the various corrosive or polluting atmosphere on the ether one. The aim of this work was to reduce this porosity. The granular distribution of sand following a Dmax linear function (Dmax is the particle's maximal diameter) enables the obtention of a maximal compactness matrix characterized by high early strengths. The addition of metakaoline and calcium carbonate improves the pastes rheological behaviour and helps to the obtention of closed pores witch reduce the hydrated cemented matrix permeability. The use of super-plasticizer and quick setting and hardening additions permits fast demolding in vibration as well as in projection. This operation is of la considerable economical interest. ]
Abdelmoumen, Saïd. "Contribution à l'étude des déformations différées sous charge constante de composites ciment-caoutchouc". Amiens, 2009. http://www.theses.fr/2009AMIE0104.
Beraldo, Antonio Ludovico. "Généralisation et optimisation de la fabrication d'un composite biomasse végétale-ciment à variations dimensionnelles limitées vis-à-vis des variations de l'humidité". Nancy 1, 1994. http://docnum.univ-lorraine.fr/public/SCD_T_1994_0076_BERALDO.pdf.
Oriol, Madeleine. "Etude de la réaction pouzzolanique ciment-métakaolin par traitement micro-ondes : application à l’élaboration de composites ciment-fibres". Lyon, INSA, 1995. http://www.theses.fr/1995ISAL0053.
The present study deals with the microwave hydration of metakaolin lended cement used in Glass Fiber Reinforced Cement Composites (GRCC). Microwave treatment conditions have been optimized and compared to the results obtained with room temperature curing. Lime consumption has been measured by means of Infrared Spectrometry and differential Thermal Analysis. It was shown that the pozzolanic activity of metakaolin is enhanced by the microwave treatment, allowing halfway reduction of the necessary amount of metakaolin to consume the total calcium hydroxide generated by cement. Mortars and RCC mechanical characteristics have been measured. It was shown that high initial resistances and law porosity can be obtained with the microwave curing technique. It appears that the temperature generated inside of the material itself leads to the thermal acceleration of setting. A modification of hydrates morphology was observed by §canning Electron Microscopy
Houssais, Loïc. "Conception et élaboration d'un banc de test infrarouge pour études à haute température de matériaux composites : application aux bétons de bois à matrice argileuse". Amiens, 2004. http://www.theses.fr/2004AMIE0418.
Siebold, Alain. "Contribution à l'étude des interfaces dans les composites à matrice ciment". Mulhouse, 1998. http://www.theses.fr/1998MULH0545.
Bouhrara, Driss. "Comportement mécanique en rigidité et à rupture d'un matériau composite fibres-ciment". Lyon 1, 1993. http://www.theses.fr/1993LYO10261.
Deschryver, Laurent. "Résistance à la fissuration des composites fibres ciment : rôle joué par les fibres". Paris, ENMP, 1989. http://www.theses.fr/1989ENMP0162.
Labbani, Fayçal. "Contribution à l'étude d'un composite cimentaire à base de déchets de caoutchouc : influence des variations de températures sur son comportement mécanique". Amiens, 2006. http://www.theses.fr/2006AMIE0605.
Alberto, Mario Michaque Miguel. "Faisabilité de composites bois-ciment destinés à la construction de maisons au Mozambique". Nancy 1, 2001. http://www.theses.fr/2001NAN10059.
Cherubin-Grillo, David. "Caractérisation et modélisation du comportement mécanique d'une plaque ondulée en composites ciment/verre". Clermont-Ferrand 2, 2001. http://www.theses.fr/2001CLF21283.
Cheumani, Yona Arnaud Maxime. "Étude de la microstructure des composites bois/ciment par relaxométrie RMN du proton". Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13827/document.
In this work, low field proton NMR relaxometry (20 MHz) was applied to study wood-bonded cement composites hydration and the behaviour of hardened composites conditioned in humid atmosphere or immersed in water. In a first part, relaxometry was used to simultaneously follow the transformation of evaporable water into hydrates and the microstructure development during cement setting and hardening. This technique was also used to observe water transfer from wood to the cement matrix and to evaluate wood cement compatibility. In the second part, the influence of wood or matrix chemical modification on cement hydration was studied. Different behaviours were observed depending on the chemical group grafted unto wood or the chemical admixture added to the matrix. In the third part, the effect of moisture and the mechanical properties of hardened composites were evaluated
Vallée, Franck. "Durabilité des composites polymères/ciment : application au cas des enduits minces sur isolants". Grenoble INPG, 1999. http://www.theses.fr/1999INPG0138.
Pascal, Serge. "Comportement mécanique de composites mortier-polymère". Châtenay-Malabry, Ecole centrale de Paris, 2002. http://www.theses.fr/2002ECAP0851.
Chadfeau, Calypso. "Caractérisations multiéchelles de surfaces cimentaires de parement en fonction de différentes surfaces coffrantes". Thesis, Strasbourg, 2020. http://www.theses.fr/2020STRAD005.
The objective of this work is to study the interaction between cement and different types of formwork surfaces by analysing the surface condition of the raw cement paste 24 hours old and that of formwork surfaces at different scales as well as their demoulding performance. Surface characterisation procedures combining interferometry, SEM + EDS, Raman spectroscopy and AFM Peak Force are developed. These multiscale characterisations allow the demonstration of the impact of the physico-chemical properties of formwork surfaces on cementitious surfaces at different scales and the analysis of their influence on adhesion to formwork. The effect of surface geometry and surface energy of formwork surfaces on the morphological, chemical and mechanical characteristics of cement surfaces is analysed, from millimetre to nanometre, with a discussion on the possible characterisation of cement phases more or less hydrated
Ngolle, IV Moussole Albert Douglas. "Modélisation du comportement mécanique des composites ciment-fibres en tenant compte de la microstructure". Lyon, INSA, 1997. http://theses.insa-lyon.fr/publication/1997ISAL0068/these.pdf.
A new analytical model for the mechanical behaviour of cement fiber composite under tensile load is proposed in this work. Short term static loads are considered. The fiber are short and with a homogeanous distribution in the composite. Their orientation angle can be probabilistic or deterministic. This model considers microstructural parameters and the qualitative dissipation of the composite. This latest is modelled in this study. The microstructural scale is the fiber scale. The composite is considered as a set of fiber-matrix cells. The shear lag concept is issued to determine the stress and strain fields in the unit cell. The homogenization process is an averaging process based on continuum mechanics, probabilistic and tensorial consideration. This model is triphasic and uses the probabilistic density function for fiber orientation as a variable, its equations depend on the qualitative dissipation kinetic of the composite. Comparing the model with experimental results and other existing models shows his good capacity to predict the composite behaviour
Ngolle, IV Moussole Albert Douglas Pera Jean. "Modélisation du comportement mécanique des composites ciment-fibres en tenant compte de la microstructure". Villeurbanne : Doc'INSA, 2000. http://docinsa.insa-lyon.fr/these/pont.php?id=ngolle_iv_moussole.
Khazma, Mahmoud. "Contribution à l’optimisation de composites cimentaires à base de coproduits du lin : procédés de traitement de la matière végétale et de la matrice ; impact de ces procédés sur les propriétés des composites élaborés". Amiens, 2008. http://www.theses.fr/2008AMIE0125.
This work is done in the processes and materials engineering group of the Laboratory of innovating technologies of the University of Picardy Jules Verne. The main goal of this work is the valorization of vegetables’ byproducts, specifically the use of flax shives as aggregates in cementitious matrix. Flax shives, like all lignocellulosic materials, are known by their high hydrophilic properties. During concrete confection, shives absorb mixing and inhibit the cement hydration. To optimize their use, these shives must be hydorphobisated. Treated shives are characterized by SEM, FTIR, water absorption…. Then, the impact of these treatments on the hydration of cement matrix and the physico-chemicals characteristics of composites are quantified and evaluated. The second way explored in this thesis is the matrix treatment. These treatments are done using molecules extracted from the biomass. The elaborated composites show a high competitive properties in comparison with composites prepared with commercial vegetables aggregates
Chafei, Sawsen. "Influence de différents traitements sur les comportements rhéologique et mécanique d'un composite cimentaire mortier-fibres de lin". Caen, 2014. http://www.theses.fr/2014CAEN2035.
The objective of this study is to avoid catastrophic failure of a cement mortar incorporating flax fibers by conferring it an increasing resistance rising with the crack length. The implemented strategy is to improve the fiber-matrix compatibility by adapting the formulation by different treatments applied to fibers and / or matrix. In the first part of this study the effects of these treatments on fiber properties are evaluated by chemical, physical and mechanical characterization of the treated flax fibers versus raw fibers. The treatments applied to the cement matrix are also evaluated. The formulated mixtures, composed of treated fibers and / or matrix with additive were characterized in the fresh state to assess the impact of treatments on the consistency and the setting of the mixture, and the cement hydration. The last part of the work is devoted to analyzing the effects of these treatments on the microstructure, physical and mechanical properties of the cement composites
Sedan, David. "Etude des interactions physico-chimiques aux interfaces fibres de chanvre/ciment : influence sur les propriétés mécaniques du composite". Limoges, 2007. http://aurore.unilim.fr/theses/nxfile/default/84a25f18-1c55-4565-bd8f-a95fa2e7ea73/blobholder:0/2007LIMO4055.pdf.
The use of hemp fibres in a cement material gives interesting properties to composites. The understanding of the interactions between the fibres and the cement matrix is essential to study mechanical behaviour of such composites. Hemp fibres, by a high content of pectins, fix calcium Ca2+ and hydroxyle OH- ions on their surface. A lack of hydroxyle and calcium ions is observed in the interstitial phase, which implies an inhibition of calcium silicate hydrates (CSH) responsible for the delay in setting time. Chemical attack of the fibres surface by an alkaline and calcium rich media, as cement paste, degrades hemicelluloses contained in the fibres and seems to roughen the surface. Quantities of sugars or uronic acids released by the fibres are too little to have an effect on the chemical properties of the solutions. Calcium ions fixation on hemp fibres surface implies a strong adhesion between them and cement matrix. So, an improvement of the mechanical properties of the composite is observed. The fibres network in composites permits an increase of the flexural strength associated to a rise of the displacement to rupture. Such composites could be consequently interesting in building applications
Laidoudi, Boubker. "Contribution à la valorisation des déchets de caoutchouc dans une matrice cimentaire : caractérisation physico-thermique et évaluation des performances à différents degrés d'humidité. Etude expérimentale et modélisation". Amiens, 2005. http://www.theses.fr/2005AMIE0524.
Turki, Mohamed. "Valorisation des granulats de caoutchouc et de fillers dans un mortier cimentaire : étude microstructurale et caractérisation expérimentale". Amiens, 2010. http://www.theses.fr/2010AMIE0106.
The work present the development of a new type of cementitious composites containing rubber aggregates. The evaluation of the influence of rubber particles on the physical, mechanical and hydric properties of mortar is developed. The study of the hydric behaviour of these composites reveled the importance of the addition of rubber aggregates in cement paste. The skrinkage and swelling derease considerably. These parameters have an important influence on the durability of these materials, and then they are a limiting factor in the cracking. In addition, the physical and mechanical properties decreases significatively when the percentage of crumb rubber increase in the matrix. A complementary study to describe microstructure allows making a correlation between them. Eventually, the addition of siliceous and limestone fillers in mortar-rubber aggregates composites permit in part to reduce the decrease of mechanical strength of specimens. The decrease of flexural strength is less than compressive strength. The measure of the elastic modulus (dynamic and static) revelled an important deformability of the specimens when the percentage of substitution with rubber particle rises
Benazzouk, Amar. "Contribution à la valorisation de déchets de caoutchouc : composites cimentaires à base de caoutchouc compact et cellulaire". Amiens, 2002. http://www.theses.fr/2002AMIE0214.
Mohamadou, Bassirou. "Contribution à la caractérisation mécanique de composites à base de ciment renforcé par fibres de verre". Lyon 1, 1994. http://www.theses.fr/1994LYO10022.
Attari, Allel. "Caractéristiques physiques et processus de migration de l'eau dans les matériaux à base de gypse et de minéraux argileux". Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0094.
After hardening, β hemihydrate plasters are essentially macroporus materials (r>1000Å), then constitute media into which liquid water can easily migrate. The aim of the present work was to remedy such an inconvenient by incorporating into the material, before hardening; finely divided solids such as mineral clays (kaolinite, montmorillonite, muscovite, talc, sepioloite and attapulgite) or a thermally activated mineral clay (meta-kaolinite) added or not to calcium hydroxide or ordinary Portland cement. The research as allowed to point out that certain precited solids idi not sensitively modify either hydratation kinetics (investigation by isothermal calorimetry) nor both compressive and flexural strength, when the content of additive solids does not exceed 10% in weight in plaster. But all added solids decrease both the pore size distribution and , except for metakaolinite-lime addition, the water migration rate into the material. He results concerning the last point have been obtained by using an original experimental set allowing the study of water migration on variable hydraulic charge. A theoretical modelling of the phenomenon implying to take into account experimental values of permeability coefficient, pore size distribution and total open porosity of the material, has been proposed. The present work has allowed to define without any ambiguity, the choice of solid additives able to resolve the set problem
Gimet-Bréart, Nathalie. "Description des évolutions physico-chimiques d'un ciment alumineux du jeune âge et au cours de son vieillissement : caractérisation ultrasonore in-situ en mode infini et en réflexion". Limoges, 2001. http://www.theses.fr/2001LIMO0004.
Goto, Tania. "Influence des paramètres moléculaires du latex sur l'hydratation, la rhéologie et les propriétés mécaniques des composites ciment / latex". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2006. http://pastel.archives-ouvertes.fr/pastel-00002110.
Tlaiji, Tala. "Développement et caractérisation du comportement thermomécanique des matériaux composites TRC". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1116/document.
In order to strengthen and protect civil engineering structures from fires, a research program was undertaken for the development of new TRC composite materials. The TRC composite generally consists of two components, the textile reinforcement and the cement matrix. The new composites of the project are formulated with an inorganic phosphate cement or an aluminous matrix with continuous textile reinforcements using glass, carbon or hybrids. The purpose of this work is to examine and develop TRC that meets the thermomechanical performance criteria. The first level of design is to define a characterization methodology, which identifies the thermomechanical characteristics and physicochemical properties of TRC subjected to high temperature. Several coupled thermal and mechanical loading regimes as well as thermal analyses were applied and taken into account for different TRC formulations. In a first experimental part, the nature of the matrix and the cooling effect on the thermomechanical behaviour of TRC were studied. The second part of the experimental work explores the thermomechanical and thermo-physico-chemical behaviour of two families of TRC. The first family of TRC was formed of a phosphate cement and E-glass textile. It examines the bond that can be developed through the fibre-matrix interface by two different geometries of textile. The effectiveness of the reinforcement is then improved by a pre-impregnation by a resin epoxy. The second family of TRC deals with the reinforcement of an aluminous matrix by carbon grids. This family has undergone several changes. Filling of the matrix with alumina and micron glass was not sufficient to improve the behaviour of TRC. A new carbon grid was then used and layers of Mat AR glass fibres were inserted into the matrix. These layers of Mat AR created good thermal insulation but presented a delamination problem. Finally, the addition of polypropylene fibres in an aluminous mortar with graded granulometry showed satisfactory results. After the search and validation of the most efficient TRC, the "heat shield" function of insulating materials was processed to improve the thermomechanical stability of TRC
Kettle, Andrew. "Plasma polymerisation for molecular engineering of carbon fibre surfaces for optimised composites". Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264641.
Astoveza, Jennifer. "Ciments composés à base d'aluminate de calcium incorporant des résidus traités valorisables". Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0075.
The pressure to decarbonize the cement industry in light of sustainability goals has been motivating the search for new types of supplementary cementitious materials (SCM) in the recent decades. Industrial residues, which otherwise end up in landfills or find low added-value applications, are of particular interest in near-zero-waste process schemes. This thesis explored the potential for valorization of pre-treated residues as SCM in calcium aluminate cement (CAC)-calcium sulfate hemihydrate (HH) system. These residues included non-ferrous metallurgy (NFM) slags, municipal solid waste incinerator (MSWI) bottom ashes, jarosite and paper-fabrication residues. Using isothermal calorimetry and mechanical strength test, a screening test was first established to compare their early-age and the long-term reactivity. The highly-amorphous NFM slags exhibited superior reactivity showing evidence of long-term (> 28 days) contribution to the mechanical strength of mortars at 30 wt% replacement level. However, the slags' slow hydration kinetics in the first days of hydration could be an issue for CAC systems, given that their applications greatly rely on their rapid-hardening property. Moreover, the amorphous nature of the NFM slags and the dominance of iron (Fe) in their composition, set them apart from traditional SCM's. As of this writing, there are only limited publications discussing the hydration mechanism of Fe in CAC-based binders. In order to overcome the slow kinetics of the slag hydration, the influence of three factors, including: (1) the proportion of sulfates by varying the CAC/HH ratio; (2) the addition of lime-rich paper residue at 5 wt% as activator; and (3) the incorporation of 30 wt% PC in ternary CAC-HH-PC systems, were investigated. For all these formulations, the early hydration reactions were characterized using isothermal calorimetry on paste samples. The dimensional stability and mechanical strength were followed using standard mortars up to 1 year curing period. Furthermore, a methodology to estimate the slag hydration degree using a non-destructive technique based on X-ray Computed Tomography (XCT) combined with volume analysis was developed in this study. Several techniques were used to follow the phase assemblage evolution, including: X-ray diffraction (XRD), thermogravimetric analysis (TGA), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). Lastly, transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and Mössbauer spectroscopy were also performed in order to gain a better understanding of the fate of Fe, the main component of the slag, during hydration
Stewart, Rebecca L. "Processing induced surface finish effects for RTM glass mat thermoset composites". Thesis, University of Warwick, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273441.
Ledhem, Ali. "Contribution à l'étude d'un béton de bois : mise au point d'un procédé de minimisation des variations dimensionnelles d'un composite argile-ciment-bois". Lyon, INSA, 1997. http://www.theses.fr/1997ISAL0052.
This experimental study focuses on the development of a clay-cement-wood, loadbearing insulating composite with small size variations. A study of the influence of this composite's constituents on its thermophysical characteristics was conducted and showed that lightening the weight by means of wood chips serves: to reduce the density of both the composite and its matrix; to decrease its mechanical strength and thermal conductivity; and finally, to generate significant size variations. Adding cement or inert fines to the water results in increasing the material's density (and, consequently, its mechanical strength) as well as in reducing these size variations. The material's composition has been optimized through establishing a compromise between minimizing the size variations and maximizing its thermal insulation capacity; nonetheless, size variations reaching 3. 5 mm/m are still encountered. In order to limit these variations to 1 mm/m, which was taken as the target value, a size variation reduction analysis was carried out on the material's elements apparently responsible for this phenomenon, being the matrix and the wood chips. This study consisted of performing various treatments on the wood chips (by impregnation, by coating and by hydrolysis) in addition to providing the matrix with a fibrous structure. It was highlighted herein that the mechanism at work behind the size variations is directly govemed by the type of transformations induced by including the wood chips in the matrix during mixing. In contrast, the instability in size of the wood itself exerts little influence on the composite's size variations after hardening. Since size variations at the limit states were confined to 1 mm/rn, we decided to assess the influence of wood chip treatment on the composite's thermal and mechanical characteristics
Dupleichs, Manon. "Développement de ciments phosphocalciques combinés à des agents d'intérêt thérapeutique". Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4100/document.
Postoperative pain following bone reconstruction is a serious complication that could jeopardize the global success of a surgery. This pain, which is highly prone to chronicization, must be controlled and minimized during the first postoperative days. This thesis consists in the development of injectable loaded calcium phosphate cements (CPCs) able to deliver in situ local anesthetics (LA). These cements, once formulated and characterized, showed an in vitro release of LA during 2 weeks. A functional evaluation of the gait was performed using the CatWalk system in an in vivo model of postoperative pain following bone reconstructive surgery. The results demonstrated significant pain relief during the short-term postoperative period. Bupivacaine-loaded CPC provided an earlier return to functional recovery than ropivacaine-loaded CPC. These CPCs would constitute a new approach to the management of postoperative pain after orthopedic bone surgery. In this local strategy, the therapeutic potential of gallium on bone disorder led us to insert gallium maltolate, GaM (antitumor, painkiller) inside CPCs. The association of casein and GaM allowed the formulation of new composite cements whose active molecule release has been then modulated. These new combined systems have the required properties for bone void filler and open great pre-clinical and clinical perspectives to treat complex orthopedic situations which currently don’t benefit from satisfactory therapeutic solutions
Soro, Julien. "Elaboration par coulage en bande et caractérisation de composites fibreux à matrice à base de ciment alumineux". Limoges, 2005. https://aurore.unilim.fr/theses/nxfile/default/277b6612-aad6-4cc7-b012-240bd5893755/blobholder:0/2005LIMO0003.pdf.
For "large public" utilisation, corresponding to materials with good thermo-mechanical properties at temperatures about 1200°C, a research program was undertaken to apply the tape casting method in to great diffusion materials such as aluminous cements (SECAR 71 – Lafarge-Alumitnates). The object is to manufacture composite materials with low cost mineral matrix reinforced with fibres in 1D or 2D configuration, which can be used in oxidizing atmosphere. The results we have obtained, show that it is possible to make by tape casting, composites with hydraulic binder matrix reinforced by ceramic fibres, presenting a non-fragile behaviour and preserving a good level of rupture strength after dehydration
Villain, Géraldine. "Caractérisation de la prise de matériaux a base de ciment par propagation d'ondes acoustiques et ultrasonores". Lyon, INSA, 1997. http://www.theses.fr/1997ISAL0077.
This thesis studies the behaviour of materials with cement pastes, by means of devices using compressional and shear waves. Materials tested, containing more or less bubbles, are aerated concrete and mortar. They are presented in the first part of this work. The second part deals with theoretical models of the behaviour of these heterogeneous materials under small strains. The first approach by periodic homogenization gives the viscoelastic, compressible, isotropic behaviour law of the homogeneous macroscopically equivalent material submitted to harmonic stress of large wave length compared with heterogeneities’ size. The second complementary approach by self-consistent method leads to an estimated value of each rheological macroscopic modulus. The third part describes the non-destructive device generating low frequency compressional and shear waves and presents analysis of experimental results. Then we study the evolving rheological characteristics during setting and the influence of preparation and formulation parameters. The forth part deals with the study of aerated concrete hardening during autoclaving process. The laboratory autoclave is equipped by ultrasonic transducers. Wave velocity measurement leads to the material mechanical evolution and the influences of autoclaving stage parameters, of formulation parameters
Li, Mengya. "Caractérisation expérimentale et modélisation du panneau composite bois-ciment". Electronic Thesis or Diss., Université de Lorraine, 2018. http://www.theses.fr/2018LORR0302.
Lightweight concretes made from wood fibres and Portland cement paste are a new alternative for the reduction of the environmental impact of buildings. They are used in sustainable constructions as secondary elements for their thermal, hydric and mechanical performance. However, the generalisation of their use is not possible without resolving certain scientific obstacles related to their characterisation. Hence the aim of the present work, which is to contribute towards their characterisation through experimentation and numerical simulation. The Young's modulus and tensile strength were measured through flexural and compression tests. A numerical model has also been developed to predict the behaviour of specimens under bending test as well as their structural response when used as permanent formwork. In particular, the model helps to choose the optimum parameters for a better design of the formwork system. The study of the hygrothermal behaviour of the wood-cement material was carried out using both experimental work and simulation. The equations of coupled heat and moisture transfers for a porous medium have been implemented in the Comsol Multiphysics® software. The developed model has been applied and validated on several dynamic responses resulting from hygro-thermal tests carried out in the laboratory. The obtained physico-thermal properties of the wood-cement composite material were then incorporated into the Abaqus code via a Umatht user subroutine to simulate its high temperature behavior. The temperature profiles are evaluated and compared with the charring tests performed using a radiant panel on samples exposed to a uniform heat flux of 6kW/m². The simulations show that the developed model is able to predict the temperature profiles, the area and the depth of the charred layer during fire exposure
Vickers, Phil E. "The adsorption of organic molecules on carbon fibre surfaces : from monolayers to composite materials". Thesis, University of Surrey, 1998. http://epubs.surrey.ac.uk/680/.
Vautard, Frédéric. "Caractérisation et optimisation des interfaces dans les composites polymérisés sous rayonnement ionisant". Mulhouse, 2006. http://www.theses.fr/2006MULH0858.
The mechanical properties of fibre-matrix interfaces in composite materials cured by ionizing beams are far lower than those of the best composites cured by thermal treatment. To optimize the carbon fibre-acrylate matrix interface, some surface treatments are studied (oxidation with nitric acid or oxygen plasma, grafting of coupling agents, coating by plasma polymerization). The evolution of the mechanical interfacial properties, measured by a pull-out test of a single fibre from a resin drop, is related to the surface state of the treated fibres (roughness, surface chemistry, surface energy) and to their mechanical properties. The optimization requires two conditions. The fibre surface, which can inhibit the matrix polymerization, has to be coated and the coating has to be functionalized with a surface chemistry adapted to the matrix chemistry and the curing mode
Yazoghli-Marzouk, Sonia. "Contribution à la valorisation des emballages alimentaires de post-consommation en polyéthylène téréphtalate et en polyéthylène haute densité : Etude de faisabilité et évaluation des performances physico-mécaniques, hydriques et thermiques". Amiens, 2005. http://www.theses.fr/2005AMIE0527.
Duplan, François. "Composites cimentaires à module d'élasticité contrôlé : conception, caractérisation et modélisation micromécanique". Toulouse 3, 2014. http://www.theses.fr/2014TOU30031.
This PhD was realized thanks to a CIFRE partnership between the company Menard and the university of Toulouse. The purpose of this PhD was to develop and study new cement-based materials destined for the CMC (controlled modulus columns) technique. This technique belongs to a wider family of ground improvement processes called rigid (or semi-rigid) inclusions, which are soil-stiffening techniques. Those cement-based materials shall respect the company specifications regarding fresh and hardened state properties. The first goal was to design mixtures compositions which properties at fresh and hardened state respect the company specifications and are optimized for the application which they are destined for. A specific attention was given to the rigidity of the material, and its brittleness when it is reinforced by fibers. Mortars incorporating expanded clay aggregates, rubber aggregates and metallic fibers were developed. The second goal was to study the efficiency of regulatory building codes formulas with the developed mortars, since most of the developed mortars do not meet with the application scopes of the building codes. A few formulas turned out to be as efficient with the developed mortars as with regular structural concrete, while others turned out to be imprecise and unfavourable to security. The third goal was to predict the elastic properties of the linear elastic properties of the developed mortars thanks to a micromechanical model adapted to the specific needs of those specific materials. This model shall replace the empirical formulas advantageously for predicting the modulus of elasticity of the developed cement-based composites
Grandin, Martina. "Tribology of Metal-Graphite Composites : A Study of Sliding Electrical Contact Surfaces". Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-329860.
Poret, Karine. "Ciment phosphocalcique et chitosane : élaboration et caractérisation d'un composite minéral-organique". Toulouse 3, 2005. http://www.theses.fr/2005TOU30046.
This study concerns to the preparation and the physico-chemical and biological properties of an organic-mineral composite for orthopedic use, formed with a natural biopolymer and synthetic phosphocalcium cement. The first part of the work deals with general information on phosphocalcium cements, chitosan and crystallization. The second part presents in the study of the physicochemical behaviour of cements with chitosan. Chitosan can be added either to the liquid phase, or to the solid phase, of the cement. The chemical transformation of the cements is not disturbed by the addition of chitosan. The setting time of the cements is modified according to the mode of incorporation and the quantity of chitosan added. The compression properties of the cements were studied. For a certain quantity and/or type of chitosan, the compressive strength of the cements was preserved or improved. The third part involves the study of the interactions between chitosan and octocalcium phosphate. The method used was constant composition crystal growth. The last part presents the results of the in vivo studies carried out at Haifa University (Israel)
Khelifi, Hamid. "Matériaux argileux stabilisés au ciment et renforcés de fibres végétales : formulation pour extrusion". Lorient, 2012. http://www.theses.fr/2012LORIS277.
The main aim of this thesis was to contribute to the study of the extrusion of cement-clay paste and the valorization of local materials in order to produce extruded building bricks. To do this, extrudable cement-stabilized argillaceous materials (kaolin) have been designed. These mix designs comply with actual requirements concerning environmental impacts (use of a significant proportion of clay) and they may be used as building materials. Bio-based fibers (flax fibers) have been incorporated. As for any other type of inclusions, flax fibers modify the rheological behavior of material at fresh state. Furthermore, their hydrophilic character amplifies the changes and has required a specific study. The mechanical perform-ances of the tested mix design and the positive effect of extrusion process as well as the addi-tion of fiber have been characterized. Such as for concrete, the Féret relationship is shown to be able to predict the compressive strength assuming that kaolin acts as a high water demand aggregate. A model for stiff paste ram extrusion incorporating the filtration phenomenon and the frictional behavior of the granular packing has been developed. This model is based on the soil mechanics approach and is able to predict the transition between pure plastic behavior and frictional plastic behavior. Finally, the mechanical and thermal performances of the cho-sen eco-friendly mix designs have been compared to those of traditional building products (concrete blocks, concrete, clay bricks, AAC. . . ). Environmental impacts of these mix design have also been evaluated and compared. It appears from this study that the extrudable cement-stabilized argillaceous materials comply with legislations concerning environmental impacts thermal comfort. They are also able to present an alternative to actual building products
Monnin, Alexandra. "Fonctionnalisations et caractérisations de surfaces par des films polythiophènes et dépôts de particules composites". Besançon, 2010. http://www.theses.fr/2010BESA2034.
The objective of this study was to synthesize composite materials made of polymer and particles on a conductive substrates. The combination of two elements of different nature allowed to obtain specific properties of the new material. This application for composite material are of potential interest to various industrial sectors :micro-engineering, optics, electronics… Initially, the surface of gold substrates was functionalized with polymer films (polybithiophene and polytris [5-(2,2ۥ-bithiophène)] méthanol]), obtained by electropolymerization. The influence of different parameters on the formation of electropolymerized films was studied : the nature and concentration of the monomer, composition of electrolyte, scan rate of film formation… Different techniques (optical and scanning electron microscopy, spectroscopic ellipsometry, AFM) were used to characterize the morphology and thickness of these films. The in situ formation of electropolymerized films was also studied, using a fixed angle laser reflectometer coupled with cyclic voltammetry. A correlation between the morphologies of the films and reflectometry signals was achieved. The results obtained were supported by measuring the refractive index and thickness of the films by spectroscopic ellipsometry and absorbance by UV-Visible spectrophotometry. Secondly, the assembly of composites particles, consisting of inorganic nanoparticles (silica) absorbed onto organic microparticles (latex) was performed on a metal surface. Micrometer-sized latex particles allowed to control their transport to the surface and the nanoparticles provided the desired functionality. The electrophoretic deposition of particles was studied as a function of different physicochemical parameters (pH, concentration and nature of organic additives, polarization…). The deposition of the composite particles may be reversible or irreversible, depending on experimental conditions. Furthermore, desorption of nanoparticles is observed in some cases. After selecting the experimental conditions for optimum deposition of composites particles (without desorption of nanoparticles), the assembly of these particles on the functionalized metal substrate by polymer film was studied. During their electrophoretic deposition, the particles absord mainly around clusters of polymer films
Dolan, Jeffrey Alan. "Characterization of Laser Modified Surfaces for Wood Adhesion". Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64352.
Master of Science
Herisson, Jean. "Biodétérioration des matériaux cimentaires dans les ouvrages d'assainissement : étude comparative du ciment d'aluminate de calcium et du ciment Portland". Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1135/document.
The need for renovation of sewer networks in major cities and the necessity to build new structures lead managers of sewer pipe and manufacturers to seek for solutions for sustainable sanitation. 9% of damages encountered in these structures can be attributed to the biodeterioration of cementitious materials. This study has two main objectives. The first one is to develop an accelerated reproducible laboratory test that gives results similar to those obtained on site. The second is to study the biodeterioration of cementitious materials in order to better understand mechanisms and more especially the difference in behavior between materials based on calcium aluminate cement (CAC) and ordinary Portland cement (OPC). Within this framework, different cement formulations were exposed in situ to identify the parameters influencing biodeterioration. Meanwhile, laboratory experiments were conducted to better understand each step of the mechanism of biodeterioration. Results of on site exposition show that materials based on CAC have a greater durability than other cement formulations. Laboratory studies assign these best performances to the aluminum content which inhibits the growth of microorganisms while protecting the matrix by precipitation of a hydrated alumina layer in the porosity and on the surface of these materials. This layer maintains the pH at 3.5-4. Surface chemistry was shown to play an important role in catalizing abiotic oxidation of H2S. The results of on-site exhibitions and various laboratory tests were used to develop an accelerated test giving promising results