Dissertationen zum Thema „Essai au feu“
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Rekik, Mohamed. „Le Feu au corps : essai sur les métamorphoses suivant l'aspect de l'évolution dans l'involution de la forme“. Paris 1, 2012. http://www.theses.fr/2012PA010589.
Der volle Inhalt der QuellePinton, Eric. „Modélisation du comportement d'un conteneur d'hexafluorure d'uranium soumis à un feu“. Grenoble INPG, 1996. http://www.theses.fr/1996INPG0174.
Der volle Inhalt der QuelleDjankoff, Christine Gamita M. „Essai d'anthropologie visuelle & sonore d'un "rite élémentaire" - Film de recherche "La joie du feu" : ethnographie de la permanence d'une praxie ontologique pyrobate & de la croyance afférente en Europe orientale“. Paris 7, 2003. http://www.theses.fr/2003PA070095.
Der volle Inhalt der QuelleNowadays in Europe, the "Nestinari" from Bulgaria, the "Anestenarides" from Northern Greece dance on burning charcoals, enlightened by the same enthusiasm as the pyrobates from septentrional Spain and the "Nyungwes of Tété" from Southern Africa : its "elementary rite of walking or dancing on fire was discussed through the perspectives of its origins, of its sociopsychological and obviously neurophysiological mechanisms — in connection with the belief of the incombustibility and insensitivity of the human body - , of its individual and collective behaviours , of its historical evolution, as well as its social meanings. This point of view relies on a zetetic methodological and philosophical tradition, related to the ethnological domain. The point was to give rise to a "transverse synergy" in order to directly involve the parallelism of the various branches of the social sciences considering the rite: and the "way of communication" as a whole, while building gradually a conception in a pilot matter thanks to visual anthropology. Its interest can thus be summarised as follows : - Allowing to deepen a assumablely not described cultural event, - Determining more accurately the influence of the social environment throughout the unfolding of this event. This research includes in its analysis the realisation of an audio-visual document in the anthropological range, the portrait of a "Nestinarka", included and argued in this digitally formatted work
Ogabi, Raphael. „Experimental study of the fire behavior of synthetic and bio-sourced composite materials impacted by heat flux density on a medium and large scale“. Electronic Thesis or Diss., Bourges, INSA Centre Val de Loire, 2024. http://www.theses.fr/2024ISAB0001.
Der volle Inhalt der QuelleWith the aim of improving the understanding of the fire behavior of synthetic and bio-sourced composite materials, the objective of this thesis is to highlight physicochemical phenomena related to fire safety for materials that can be used in applications of aeronautics and/or automobiles. In this context, part of the experimental tests was carried out using the NexGen burner developed according to FAA requirements to carry out fire certification tests. The second part of the results was obtained using a cone calorimeter to assess the fire behavior of composite materials on a medium scale. In addition to fire certification tests, this research study focused on the development of bio-sourced composite materials. Indeed, considering the non-biodegradable nature of synthetic composite materials such as carbon-PEKK, carbon-BMI, and carbon-phenolic, the lack of work dealing with the subject and the problem of global warming, this thesis proposes a physical characterization -chemical of bio-sourced composite materials subjected to different heat flow densities. The bio-sourced composite materials manufactured as part of this thesis consist of flax fibers and banana fibers; manufactured using the VARTM method. To improve the thermo-physical properties of these materials to increase their performance from a fire safety point of view, an additional layer of flame retardant was applied to their surface. For the study of the thermal degradation of bio-sourced materials, three heat flow densities were used, notably 20, 35, and 50 kW/m². The parametric study focused on the fire performance index, the fire growth index, the mass loss, the pyrolysis flow rate, the surface temperature of the rear face and the front face of the sample, and the gaseous emissions obtained for each test configuration. Using the results, it is shown that for the configuration characterized by the most intense flame, the carbon-PEKK composite material is the most thermally stable. In addition, for the three heat flows studied, the bio-sourced composite materials present different thermo-physical behavior. Indeed, on a medium scale, materials based on flax fibers have thermal properties superior to those of materials based on banana fibers. However, on a large scale, the opposite observation was highlighted. It appears that the thermal properties of bio-sourced materials strongly depend on their size
Filleron, Jean-Charles. „Essai de géographie systématique : les paysages du Nord-Ouest de la Côte d'Ivoire“. Phd thesis, Université Toulouse le Mirail - Toulouse II, 1995. http://tel.archives-ouvertes.fr/tel-00130787.
Der volle Inhalt der QuelleLa méthode d'analyse des milieux et des paysages est celle de l'« École d'Abidjan » dont Jean-Charles Filleron a été l'un des fondateurs. Trente mois ont été consacrés à la description de 826 relevés de la végétation, de la surface du sol et du sol sur le terrain et plus de 2500 photos aériennes ont été analysées du double point de vue de la forme et du milieu. Les traitements statistiques multivariés, ACP, AFC et classifications ont permis la réalisation d'une systématique des milieux et paysages aux différentes échelles scalaires.
Le champ d'application est le Nord-Ouest de la Côte d'Ivoire, vaste territoire de 49000 km2 dont l'essentiel est dévolu aux savanes plus ou moins boisées couvrant plateaux cuirassés et inselbergs. Sur ce territoire faiblement peuplé, l'auteur met en évidence le rôle des sociétés rurales... et de la nature du substrat rocheux... dans la diversité des milieux et des paysages et renouvelle le discours écologique sur les milieux tropicaux.
Márquez, Costa Juan Pablo. „Caractérisation et modélisation des interfaces dans les composites organiques stratifiés à haute température : Application à la tenue au feu des structures aéronautiques PhyFire LOT 2 - Développement de modèles de comportement du composite Caractérisation en température de la ténacité en mode II des interfaces des CMO en utilisant l’effet Joule Caractérisation du comportement visqueux des interfaces CMO et influence sur la propagation de délaminage Convention PhyFIRE 2 - LOT 2 : Développement d’un cadre de modélisation pour les matériaux composites Durabilité des matériaux composites en conditions extrêmes : vers la prédiction des propriétés de tenue au feu Durability of Composite Materials under Severe Temperature Conditions : Influence of Moisture Content and Prediction of Thermo- Mechanical Properties During a Fire Towards the Prediction of Sandwich Composites Durability in Severe Condition of Temperature : A New Numerical Model Describing the Influence of Material Water Content during a Fire Scenario“. Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2021. http://www.theses.fr/2021ESMA0004.
Der volle Inhalt der QuelleWithin the framework of the fire resistance of composite materials, it is necessary to assess the degradation of their thermal and mechanical properties due to mass losses, matrix cracking and/or delamination cracks. Nevertheless, few studies in the literature about the temperature resistance of aeronautical composites concern the mechanical behaviour and the rupture of interfaces before any thermal degradation,subject which is the main topic of this work. Thus, the objective is to propose a failure model concerning both the delamination crack initiation and growth under thermomechanical loads. Much of this work has focused on the characterisation of interface properties using an analysis of mode II crack propagation tests for Joule heated specimens. These numerical analyses show that the ply behaviour does not explain the macroscopic pseudo-ductile response observed experimentally. Thus, a test-calculation dialog method, comparing the kinematic fields measured by digital images correlation and those simulated by finite elements, underlines the importance of the viscous behaviour at the interface scale. By a similar FEMU approach the parameters of a cohesive-type fracture law have been identified in temperature and taking into account the different sources of uncertainty. This work highlights the similarity between plane and out-of-plane shearing, both on behaviour and on failure. In parallel, the analysis of temperature resistance tests by laser impact made it possible to establish a crack initiation criterion by a coupled stress and energy approach. A comparison of this criterion with the parameters of the cohesive zone law previously identified makes it possible to discuss about the modeling scale of the interface
Fernandez, Cristian. „Caractérisation et modélisation du comportement au feu de poutres en bois lamellé collé“. Nancy 1, 2006. http://www.theses.fr/2006NAN10099.
Der volle Inhalt der QuelleWood is increasingly being used as building rnaterial due to its specific characteristics, such as its high insulating capacity given by its low thermal conductivity. Nowadays, wood may be considered as an answer to the cUITent energy cri sis, resulting in cost reduction in energy consumption. Wood is classified as a combustible material, which makes us doubt about its structural tire resistance. However, contrarily to !bis idea and spite of its classification, wood provides an excellent tire resistance. It bas long been recognized that under a tire situation, a wood structure loses resistance more slowly than a steel or concrete structure. The particular context of this study relates to tire applied to glulam. Currently, the most used adhesives in the glulam industry are: Resorcinol-Formaldehyde, Phenol-Resorcinol-Formaldehyde, Urea-Formaldehyde, and MelamineUrea-Formaldehyde. The main problem arising from these adhesives is their two-component fonnulation (adhesive and hardening), making their usage more complicated. Moreover, wood bas to be dried before gluing, which in turn increases the costs and building time. Ln order to solve these inconveniences, there are currently other solutions in the market, e. G. Polyurethane adhesives consist of only one liquid component applied directly on wood even if it is wet. However, this kind of adhesive shows a high level of creep at high temperatures, which rnay lead to a dangerous situation during a tire. Ln the development of !bis thesis, we characterized the behavior of structural polyurethane adhesives under tire, considering as parameter for comparison the most used adhesives, i. E. Phenol-Resorcinol-Formaldehyde and MelamineUrea-Formaldehyde. As a first stage we characterized the different adhesives subject to high temperatures (between 30°C and 250 °C). As a second stage we established the tire behavior of glulams under the different studied adhesives. For !bis, we chose to perfonn tests with a radiant panel at constant flow (15, 25, 45 and 60 kW/m2). The main result was that the kind of adhesive used in glulams bas no influence on tire resistance. The final stage of fuis study consisted on modeling the different occurring phenomena: A thermal model through a finite element allowed to follow-up in time the temperature distribution in the glulam transversal section subject to a heat flow. By integrating the stiffness database and the elasticity modulus resulting from the creep tests, we have been able to predict the creep behavior and failure time for a glulam subject to a temperature flow that simulates a tire. The results agree with the tests and show that the kind of adhesive bas no influence on tire resistance as the char layer that forms in the glulam surface is a good insulator that limits the depth of the wood darnaged by temperature and thus, its loss of mechanical resistance
Nguyen, Manh-Hung. „Évaluation des performances de protections passives au feu pour les structures métalliques“. Electronic Thesis or Diss., Université Clermont Auvergne (2021-...), 2023. http://www.theses.fr/2023UCFA0046.
Der volle Inhalt der QuelleSteel-timber hybrid structures are becoming more and more common in the construction industry. They offer high practical advantages as sustainable solutions with high load-bearing capacities and fire resistance. However, due to steel thermal conductivity and the decrease of mechanical performance with high temperatures, steel structures need to be protected in case of fire. Wood is occasionally used as passive protection of steel to maintain its mechanical strength as long as possible with the aim to prevent structural collapse under fire. This thesis aims to analyse the thermal behaviour of hybrid steel-timber elements through experimental tests and numerical modelling. Experiments in the furnace are performed to obtain the evolution of temperature on the steel profile surfaces and inside the timber element. Thus, thermocouples are installed on the steel profile surface and different depths of timber elements. The fire tests were performed on various steel-timber combinations using T and I steel cross-sections with various wood species. A high-temperature furnace up to 1200 °C built in the laboratory was used. The results show that wood provides significant protection to the steel cross-section mainly the fully encapsulated IPE profile. Wood behaves as an insulating material that significantly reduces the temperature rise in steel. This solution contributes to the development of passive protection of steel structures using bio-based materials. The experimental results are compared to those obtained through thermal simulations using Abaqus software. The comparison shows that the numerical model can be used to evaluate the temperature increase in the steel element protected by timber in high-temperature conditions
Rizk, Georgio. „Durabilité des matériaux composites sandwichs en conditions extrêmes : tenue au feu et évolution des propriétés mécaniques“. Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4098/document.
Der volle Inhalt der QuelleComposite materials play an increasingly important role in our society in many fields (aeronautics, naval, civil engineering), because of their advantages in terms of lightness, unalterability and rigidity. It is therefore essential to understand and evaluate their properties in the long term (durability). However, the use of this type of material requires special precautions, particularly with regard to fire resistance. Indeed, sandwich composites are highly flammable and poorly heat resistant. The aim of this thesis project is to study in a combined way the thermomechanical durability (fire resistance) of polymer matrix composite sandwich materials by means of experimental measurements with a calorimeter cone. It is also a question of modeling the variations of mechanical properties induced as a function of the temperature and the combustion time, using a multiphysical model based on a finite element approach (Abaqus). The processes of thermal degradation of these materials are presented as a function of temperature and time, as well as behavior laws and of thermal and mechanical properties predictions. An improved thermal numerical model is programmed and validated in relation to experimental fire resistance measurements (oven, calorimeter cone). Confrontations between experimental measurements and numerical model, performed under several fire resistance scenario configurations, are carried out in order to understand and predict the behavior and thermomechanical properties of composite sandwich materials
Abdallah, Rafik. „Comportement au feu des briques de terre comprimée“. Thesis, Pau, 2021. http://www.theses.fr/2021PAUU3065.
Der volle Inhalt der QuelleThe present PhD thesis addresses the high temperature behavior of a compacted raw earth material and a cement stabilized earth material, both of which are likely to be used in fire-prone buildings.A complete campaign of laboratory tests was carried out on the two materials. Residual tests, which included mechanical, thermal and permeability tests were performed after slowly heating at a rate of 2 °C.min-1 using an electric furnace to attain temperatures of 80 °C, 120 °C, 200 °C, 350 °C, 450 °C and 600 °C. Then, fire tests were performed, which allowed for the exposure of these materials' bricks to a high heating rate using a mobile gas furnace designed to follow an ISO 834-1 fire curve in order to simulate a real-life fire accident in a building.Besides the effect of the material composition on the high temperature behavior, the effect of the water content on this behavior was also studied after subjecting the samples of the two materials to different relative humidities (RH): dry condition, 50 % RH, 75 % RH and 100 % RH, at an ambient temperature of 23 °C. As a result, the behavior of these materials is better characterized, allowing for a better understanding of real-world applications in a variety of environments.The material's composition and water content influence significantly its behavior at high temperatures. Following the fire tests, the samples were classified into two categories based on their composition and water state: thermally stable and unstable. The observed differences in behaviors have been ascribed to thermomechanical phenomena. They are caused, on the one hand, by the formed thermal gradients induced as a result of the consequent thermal stresses, which decrease as the water content increases, and, on the other hand, by the intrinsic mechanical properties of the materials (which decrease with the water content). These factors were subsequently demonstrated to play a major role in the material's fire behavior and load-bearing capacity at high temperatures, as assessed by mechanical loading of the samples during fire tests
Beaugendre, Agnès. „Self-stratifying flame retardant coatings for plastics“. Electronic Thesis or Diss., Lille 1, 2017. http://www.theses.fr/2017LIL10114.
Der volle Inhalt der QuelleThis PhD work is a proof of concept on the design of flame retardant (FR) self-stratifying coatings for polycarbonate (PC). This one pot process allows an eco- and smart-development of new products while reducing cost, processing time and solvent emission. In this work, two original self-layering coatings based on epoxy /silicone and /fluoropolymer blends were developed. Their perfect stratification was evidenced using different techniques, in a thickness range up to 130 µm. The influence of solvents characteristics, hardener, curing conditions, fillers and their incorporation phase was studied. Finally, the system diluted in butylacetate: xylene (1:1) leads to the best layering and adhesion, with the thermoplastic phase located on the top of the film. The FR fillers tested (iron oxide, calcium carbonate and two phosphorus based additives) do not affect the layering when introduced up to 10 wt.%. However, visual appearance and adhesion are strongly dependent on the solvent used. The best improvements in terms of FR properties, adhesion and weatherability (temperature, UV, humidity) were obtained by adding micrometric Fe2O3 particles: it allows the formation of a protective barrier which limits substrate/flame mass transfers, and prevents from the yellowing of the system under UV. Although Fe2O3 catalyzes the thermal degradation of the fluorinated resin, the coating reduces flame spread, dripping and slightly promotes the formation of a char. When added to the silicone-based blend, the thermal stability is improved, which allows reducing the combustibility and ignitability of the coated PC. Finally, those properties are relatively maintained after 8 weeks of ageing
Magniez, Labalette Carole. „Nouveaux textiles à performances au feu et à tenue à la chaleur améliorées“. Lille 1, 2002. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2002/50376-2002-77.pdf.
Der volle Inhalt der QuelleDépinoy, Florent. „Élaboration d'élastomères thermoplastiques ignifugés : étude des relations structure / propriétés“. Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10038.
Der volle Inhalt der QuelleThe aim of this study is to fireproof thermoplastic elastomers based on polyolefins (TPa). The studied TPa are blends of polypropylene (PP), ethylene propylene copolymers (EPDM) and hydrogenated styrene butadiene rubber (HSBR). The elastic properties of TPa based on PP/HSBR blends are closed to hyperelasticity when the level of HSBR is high (between 75 and 100% in mass of the polymers) and these properties are higher than those observed for PP/EPDM blends. These properties can be explained in particular by the higher miscibility of HSBR with PP, when compared with EPDM. The incorporation of additive based on ammonium polyphosphate (APP) to fireproof the TPa blends leads to intumescent formulations. Concerning the elastic behaviour, this incorporation mostly modifies the elongation at break of the TPa blends. Depending on the configuration of the sample during the test (horizontal or vertical test), the obtained fire properties are different. This difference is linked to the viscosity of the formulation in fire conditions: if the sample is in horizontal configuration during the test, the viscosity is less important than when the sample is vertical. When the sam pie is horizontal, HSBR-based intumescent formulations have a better fire behaviour than EPDM-based ones. These differences are explained by the fact that the intumescent structure is more stable in the case of PP and HSBR than in the case of EPDM: wh en the intumescent structure is formed, EPDM does not react with the additive, whereas PP and HSBR do react. This is the consequence of the higher viscosity of EPDM during the intumescence phenomena, compared to PP and HSBR
Flambard, Xavier. „Résistance à la coupure, à la perforation et au feu de structures textiles maillées“. Lille 1, 2000. http://www.theses.fr/2000LIL10155.
Der volle Inhalt der QuelleBensaad, Bourassia. „Étude expérimentale de l'évolution et de l'établissement de l'état de surface d'un matériau métallique en contact avec un plan de saphir : application à la modélisation des résistances thermiques de contact“. Nantes, 2008. http://www.theses.fr/2008NANT2037.
Der volle Inhalt der QuellePrimarily experimental, the present study aims at the observation of the evolution of the TCR and the geometrical characteristics of an interface according to the contact pressure; this in order to improve the models of TCR proposed by certain authors. Among these characteristics, those which interest us more particularly are the real rate of contact solid-solid S*, the density of points of contact N and the separation distance d. Our principal motivation is to establish the laws of evolution of these three parameters then to correlate them with the TCR obtained by thermal measurement. We developed an experimental methodology allowing to carry out thermal measurements of the TCR and measurements of the micro-geometry of the contact and its deformations. Micro-geometrical measurements are based on non-conventional techniques calling upon laser profilometry and the imagery. The test of micro-hardness can also be of great importance for the estimate of the parameters characterizing the micro-geometry of the interface solid-solid. We are interested in an interface of contact between a plate of transparent, smooth and infinitely rigid sapphire and a rough and deformable metallic material. The experimental study is based on an experimental design initially aiming at emphasizing the behaviour of the TCR according to the parameters S* N and d. This experimental design is also built with an aim of revealing the influence of the topography and the development of surface on these three parameters of contact by the means of the parameters of roughness and the Hv micro-hardness. The experiments are undertaken on two couple’s materials brass / sapphire and steel / sapphire and three different surface qualities: controlled, electro-eroded and turned. The tests of reproducibility of thermal measurement show the great reliability of the device carried out. The profilometric study shows that electro-eroded surfaces and rounds can be considered Gaussian then controlled surfaces are not it. The evolution of the real rate of contact S* according to the contact pressure is studied primarily on controlled surfaces (N constant). S* is considered of three way different: The first consists in analyzing the curves of Abbott raised after each loading, the second fact call to the model of Bowden and Tabor S*=P/H and with the concept of effective micro-hardness Hc and in the third we tried to determine it by a specific treatment of the photographs of the interfaces to metal /sapphire. The evolution of the density of points of contact N according to the load is observed for the couples surfaces magnet-eroded / sapphire and surfaces turned / sapphire. It is given primarily by the imagery. The evolution of the distance from separation of the average plans of surfaces d in contact is obtained by considering d equal to the parameter of roughness RP raised before loading and after each loading. The experimental results obtained show that the behaviour of the TCR according to the contact pressure, of the roughness and the nature of materials in contact, is in conformity with the literature. The results of the estimate of the TCR according to the parameters of contact S*, N and d are divided into two parts: the first relates to controlled surfaces and the second relates to "electro-eroded and turned random surfaces. For the studied samples, the distance from separation of the average plans of surfaces in contact d is considered equal to the parameter of roughness RP raised before loading and after each loading. The results of the estimate of the real rate of contact show that the profilometric technique suggested at the time of this study is more adaptable in the cases of stepladder of roughness (surfaces with strong roughness). With strong loads, this technique can give very satisfactory results. The comparison of the values of the TCR estimated according to S*=P/Hc with those obtained by thermal measurement shows a great relevance of the model Boden and Tabor, using the notion of the effective micro-hardness Hc. One notes that this model masks the presence of several scales of roughness. One also shows that the S*=P/Hv model over-estimates the real rate of contact, his use gives values of TCR lower than those obtained by thermal measurement. The comparison of the TCR estimated according to the parameters of contact with that of the TCR obtained by thermal measurement shows that it does not matter the curve of N used, the use of the model of CMY gives values of the of the same TCR order of magnitude as those measured. The model of Bardon gives values quite higher than those measured except for the very strong loadings. This result can be justified by the fact that the model of CMY is adapted for Gaussian surfaces whereas the model of Bardon is based on the assumption of the uniformity of all the points of contact
Cochard, Jean-Patrick. „Influence de la formulation sur les propriétés physico-chimiques et la cristallisation de verres d'aluminosilicates“. Paris 6, 2012. http://www.theses.fr/2012PA066689.
Der volle Inhalt der QuelleDuring this thesis we studied the dependence of the crystallization at high degree of supercooling and the sintering of peralcaline melts of the system SiO2-Al2O3-FeO-CaO-MgO-Na2O-K2O on the nature and concentration of alkalis (Na and K) and alkaline earths (Ca and Mg), and also on the addition of nucleating agents (Cr, Ti, Zr). For most compositions, crystallization takes place at the surface and the first phase to precipitate is a nepheline. NanoSIMS and DRX analyses demonstrate that these crystals get enriched in potassium upon heating, the low of this ion at the lowest temperature is due to its stabilization in the residual liquid as it acts as a charge compensator of Al3+ in tetrahedral coordination. For this reason, upper K2O contents of the initial glass composition lead to a decrease of the kinetics of crystallization. Sintering mainly depends on liquid viscosity but also on the kinetic of crystallization and surface tension, so that it presents mixed alkali (Na/K) and mixed alkaline earth (Ca/Mg) effects. The addition of ZrO2+TiO2 = 4 mol% leads to volume crystallization of a nanometric (40 nm) mixed oxide (containing Mg, Zr, Ti) at low temperature. This early crystallization contributes to increase strongly the viscosity of sample and thus, to shift sintering to higher temperatures. Disregarding other relevant industrial parameters, it would be beneficial to increase highly the MgO, K2O and ZrO2+TiO2 concentrations in order to optimize the high-temperature stability of glass wool or this range of composition
Belva, Frédéric. „Synthèse et caractérisation de matériaux hybrides Polyuréthane/Polydimenthylsiloxane : compréhension de leur comportement au feu“. Lille 1, 2005. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2005/50376-2005-144.pdf.
Der volle Inhalt der QuelleAdanmenou, Roland. „Mesures à échelle réduite de paramètres pertinents issus de scénarios feu“. Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R028.
Der volle Inhalt der QuelleThe evaluation of the reaction and resistance to fire of materials is of prime importance for the protection of goods and people. This evaluation is usually carried out using standardized tests, which are time-consuming, expensive, and often require large samples. In the literature, several bench-scale tests already exist that mimic specific fire scenarios such as electrical fires, building fires, etc... However, testing materials exposed to high heat fluxes or in other words in extreme conditions, from fires such as BLEVE, pool fires, and jet fires are usually carried out only at large scale. The objective of this Ph.D. work is to develop at a reduced scale, a bench to evaluate the fire behavior of materials, and to perform a rapid screening (high throughput approach) for the development of new materials. The test can reproduce at a laboratory scale and under perfectly controlled conditions, the thermal constraints resulting from extreme fires. This unique bench-scale test is equipped with well-controlled measuring instruments and it enables us to examine the fire behavior of materials subjected to high heat fluxes. Considering the high thermal fluxes generated by the extreme fires, the steps in developing the bench-scale test in terms of calibration and validation on a steel plate are presented. The test can reproduce heat fluxes between 100 and 300 kW/m² (and even beyond). To study the performance and behavior of materials other than steel, tests were performed on intumescent epoxy-based paints. The obtained results are presented and discussed. Simple numerical models are also proposed in this work. These numerical models allow, on one hand, to identify and quantify the boundary conditions on the exposed side and on the other hand to simulate the performance of an intumescent paint, which has been tested on the bench-scale test
Adanmenou, Roland. „Mesures à échelle réduite de paramètres pertinents issus de scénarios feu“. Electronic Thesis or Diss., Université de Lille (2018-2021), 2020. http://www.theses.fr/2020LILUR028.
Der volle Inhalt der QuelleThe evaluation of the reaction and resistance to fire of materials is of prime importance for the protection of goods and people. This evaluation is usually carried out using standardized tests, which are time-consuming, expensive, and often require large samples. In the literature, several bench-scale tests already exist that mimic specific fire scenarios such as electrical fires, building fires, etc... However, testing materials exposed to high heat fluxes or in other words in extreme conditions, from fires such as BLEVE, pool fires, and jet fires are usually carried out only at large scale. The objective of this Ph.D. work is to develop at a reduced scale, a bench to evaluate the fire behavior of materials, and to perform a rapid screening (high throughput approach) for the development of new materials. The test can reproduce at a laboratory scale and under perfectly controlled conditions, the thermal constraints resulting from extreme fires. This unique bench-scale test is equipped with well-controlled measuring instruments and it enables us to examine the fire behavior of materials subjected to high heat fluxes. Considering the high thermal fluxes generated by the extreme fires, the steps in developing the bench-scale test in terms of calibration and validation on a steel plate are presented. The test can reproduce heat fluxes between 100 and 300 kW/m² (and even beyond). To study the performance and behavior of materials other than steel, tests were performed on intumescent epoxy-based paints. The obtained results are presented and discussed. Simple numerical models are also proposed in this work. These numerical models allow, on one hand, to identify and quantify the boundary conditions on the exposed side and on the other hand to simulate the performance of an intumescent paint, which has been tested on the bench-scale test
Réti, Christelle. „Procédés d’élaboration de matériaux biosourcés à propriétés retard au feu améliorées : application à l’acide polylactique“. Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10088/document.
Der volle Inhalt der QuelleThe aim of this study is to evaluate the efficiency of different intumescent formulations to flame retard polylactic acid (PLA) by the incorporation of a phosphorous flame retardant compound (APP) and products coming from renewable resources. PLA/APP/starch composite shows the best fire retardant properties. Upon heating, the material forms a foamed cellular charred layer which protects the underlying material from the action of heat flux and flame and slows down heat and mass transfer between the gas and the condensed phase. The efficiency of intumescent structure can be explained by the viscosity of the formulation. Moreover, the explanation of the improvement of the fire properties is because of chemical reactions between the components of the formulation leading to thermally stable species like phosphocarbonaceous compound. Several solutions have been studied to improve mechanical properties of intumescent formulation
Nahhas, Fadi al. „Comportement thermo-mécanique des murs en maçonnerie de blocs creux en béton sous l'action d'un feu conventionnel“. Université de Marne-la-Vallée, 2004. http://www.theses.fr/2004MARN0197.
Der volle Inhalt der QuelleThis work is devoted to the implementation of a methodology comprising the various modeling and experimental tools which make possible to interpret analytically the behaviour of masonries of hollow concrete blocks observed during fire tests. The test results of fire resistance on two types of materials having a very different behavior are presented. Three models have been elaborated in this work : - a one-dimensional thermal model by the finite differences method taking into account the principal physical phenomena characterizing the thermal transfers (conduction, radiation and evaporation of pore water) ; - an analytical thermo-elastic model under one and two dimensional versions ; - a thermo-hygro-mechanical model representing the mortar of the blocks by an unsaturated porous media. The implementation of the thermo-hygro-mechanical model led us in particular to revisit the expression of biphasic gas flow corresponding to the diffusion (Fick’s law) and to filtration (Darcy’s law) and to clarify the concept of mean velocity of gas in this type of modelling. A parametric study intended to evaluate the influence of the various parameters characterizing the unsaturated porous media was carried out. The whole of these models is fed by thermomechanical experiments on the materials which constitute the blocs. The adopted one-dimensional modelling makes it possible to reproduce with a good approximation the temperatures measured inside the blocks during the experiments. The application of the thermo-hygro-mechanical model made it possible to represent the physics of vapor flows and phase change within materials. Lastly, the use of the two thermo-mechanical models showed that the one-dimensional model is badly adapted to represent the thermo-mechanical behaviour of the walls. The twodimensional thermo-mechanical model allows a suitable evaluation of the behaviour of walls and also allows an explanation to the difference between the tow kinds of behaviour which are observed experimentally
Marquis, Damien. „Caractérisation et modélisation multi-échelle du comportement au feu d'un composite pour son utilisation en construction navale“. Nantes, 2010. http://archive.bu.univ-nantes.fr/pollux/show.action?id=e12b0e51-8c8f-4ce3-915a-e1dc8e9588d8.
Der volle Inhalt der QuelleThis thesis work comes within the framework of a collaborative research project, dedicated to the use of composite materials in shipbuilding by a fire safety engineering based approach. The aim was to check, characterize and modellize the fire behaviour of a sandwich composite, prerequisite for the introduction of this product in the shipbuilding. To achieve this, a method based on a combined test-simulation approach, with increasing scale and complexity, was used. The analysis of the fire behaviour of the material was carried out from matter scale, up to an end use representative scale, through five successive scale levels. Experimental characterization was performed using standard test benches as well as metrological reference benches. Meanwhile, an advanced numerical simulation tool was used to simulate the thermal degradation, combustion and flame spread processes, for this sandwich composite. The practical application of this work was finally to study the fire growth hazards, through simulations of real scale fire scenarios onboard a ship integrating composite materials
Richard-Campisi, Laurence. „Modélisation du comportement au feu et de la dégradation thermique de tissus d'ameublement“. Lille 1, 1995. http://www.theses.fr/1995LIL10120.
Der volle Inhalt der QuelleAwad, Carmen. „Études numériques et expérimentales des feux marginaux“. Thesis, Corte, 2021. http://www.theses.fr/2021CORT0001.
Der volle Inhalt der QuelleWildfire suppression begins before the start of a fire incidence with the application of many proactive prevention policies. One of the most common method is the reduction of the fuel load accumulation by using controlled fires techniques also called prescribed fires. These fires are often conducted in forests and their intensity must be low to prevent any major damage on trees and on the soil. Thus, they must propagate under marginal conditions. So, a slight modification of the propagation conditions can cause their extinction. Indeed, the probability of sustainability of this type of fire depends on several natural factors (ambient temperature, relative humidity, wind speed, etc.) and also on the fuel properties (water content, shape, size, density, specific heat of combustion…). The aim of this study is to identify the fuel properties allowing fire propagation under these particular conditions. Also, the influence of some fuel properties, and of meteorological conditions (wind speed, ambient temperature, etc.) on the behavior of marginal fires and especially on the fuel moisture content of extinction are investigated.During a first work about the determination of the threshold value of the fuel moisture content involving fire extinction under no wind and no slope conditions, three models were used: a complete physical model, based on a multiphase formulation (“FireStar2D”), an analytical model published in 2014 by Balbi et al., and two experimental models. The first one is based on experimental tests carried out in the UMR SPE 6134 laboratory at the University of Corsica and the second one is an empirical model proposed by Wilson in 1985. Thus, field scale simulations were carried out using FireStar2D, with grassland and shrubs as fuel under conditions of light wind and no slope. Moreover, laboratory scale experimental burnings were conducted with excelsior fuel beds. The different results of the simulations and the burning tests are in agreement with those obtained with the semi-physical model. In addition, the effect of fuel load and the LAI, « Leaf Area Index », on the fuel moisture extinction threshold are studied.In a second study, several field scale numerical simulations are conducted with grassland under non-zero wind conditions in order to relate the fuel moisture content threshold to wind speed and to fuel load. This study also allows us to evaluate the influence of wind speed and fuel moisture content on marginal fire behavior and especially on flame characteristics.The results are encouraging and interesting to operational people working in fire management and firefighting fields, given the importance of marginal fire applications in these two domains
Lucchesi, Caroline. „Etude du mouvement d'un fluide de masse volumique entre deux compartiments reliés par une ouverture de type porte : application à la propagation de la fumée d'incendie“. Aix-Marseille 2, 2009. http://www.theses.fr/2009AIX22053.
Der volle Inhalt der QuelleLabidi, Sami. „Élaboration et caractérisation de nanocomposites argiles organo-modifiées/matrices polyéthylène et poly(ε-caprolactone) préparés par extrusion bivis“. Paris, ENMP, 2010. http://www.theses.fr/2010ENMP0056.
Der volle Inhalt der QuelleThe objective of this work was to produce organo-modified clays (OMMT)/HDPE and OMMT/Poly(ε-caprolactone) nanocomposites in order to optimize their global performances. The first part of the study was devoted to the achievement of a maximal dispersion of the clay sheets through the optimization of processing parameters for the twin screw extrusion. The use of a shearing profile coupled to a high mixing speed at the highest temperature was necessary to improve the tensile mechanical properties of PCL. However, its thermal stability and fire behavior appeared insufficient after OMMT incorporation. The use of flame retardants proved to be necessary. The use of phosphinates with synergistic agents allowed the fire reaction of the polymer matrix to be significantly improved. The second part of the study consisted in the development of relevant compositions and process for the production of a flexible thermoplastic sheet for applications in the nuclear area. This HDPE and OMMT based film was dedicated to make up for the drawbacks of existing protection sheets containing halogenated flame retardants
Victor, Clément. „Etude du comportement au feu d'assemblages titane-composite pour l'aéronautique“. Electronic Thesis or Diss., Normandie, 2023. http://www.theses.fr/2023NORMIR38.
Der volle Inhalt der QuelleThe development of increasingly lightweight aircraft with greater use of carbon fibre-reinforced polymer matrix composite parts raises a number of questions about on-board safety, particularly in terms of how materials and structures behave when exposed to fire. If a fire occurs in the engine environment of an aircraft, the materials constituting the aerostructures are subjected to high temperatures and must therefore meet safety requirements. Organic matrix composites have very complex thermal, chemical and mechanical behaviour that, when combined with very hot metal parts, could compromise the fireproofing capability of these structures. Thus, the major ambition of this thesis work is to gain a clearer understanding on the fire behaviour of titanium-composite assemblies
El, Hussieny Ossama. „Modèle numérique de simulation du comportement au feu des ossatures métalliques“. Châtenay-Malabry, Ecole centrale de Paris, 1988. http://www.theses.fr/1988ECAP0076.
Der volle Inhalt der QuelleBensalem, Hadjira. „Calcul non linéaire des structures en béton : cas particulier du béton soumis au feu“. Electronic Thesis or Diss., Université Grenoble Alpes, 2022. https://thares.univ-grenoble-alpes.fr/2022GRALI014.pdf.
Der volle Inhalt der QuelleThe serious fires that have occurred in recent decades on concrete structures or housing such as those in the Channel Tunnel (1996) or Mont Blanc (1999) have brought the issue to the fore of concrete subjected to fire and its consequences. Ordinary concrete is, however, renowned for its good fire resistance. But the appearance and use of high-performance or ultra-high-performance concretes, while solving unprecedented technical problems, simultaneously pose the problem of their greater sensitivity to fire due to their greater compactness. This study is a contribution to the understanding of thermal degradation processes by an experimental and numerical approach. In the experimental approach, high performance concrete specimens-slabs formulated from standardized sand and instrumented with thermocouples were subjected to thermal spalling tests following the standard ISO834 fire temperature curve of the Eurocode 2. Different thermal and event data collected during and after the tests were analyzed. The time to first burst, the temperature of the furnace and that of the concrete to the first burst as well as the debris produced were characterized. Using some of the experimental results as input data, numerical modeling allowed the temperature field in the specimens to be determined satisfactorily during testing. In some cases, the use of the technique of analysis by reverse method has been necessary. By subsequently using the thermomechanical approach and by relying on Mazars's isotropic damage behavior law, it was possible to calculate in particular the damage field in the test specimens-slabs during the various tests. The comparison of the results of the numerical modeling with those of the experiment showed that the modeled damage field is likely to account for the thermal degradations observed during the tests both in terms of extent and depth
Audouin, Laurent. „Etude de la structure d'une flamme simulant un incendie de produits industriels : caractérisation et modélisation de cas réels de feux“. Poitiers, 1995. http://www.theses.fr/1995POIT2354.
Der volle Inhalt der QuelleOpdebeck, Frédéric. „Etude numérique et expérimentale du transfert d'énergie laser à l'interface d'un système d'allumage et d'une composition pyrotechnique“. Orléans, 2002. http://www.theses.fr/2002ORLE2045.
Der volle Inhalt der QuelleDilger, Melvin. „Flame retardant expanded polypropylene for applications in electric vehicles : design and mechanism of action“. Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR066.
Der volle Inhalt der QuelleToday the sector of transport is changing with the transition from thermal vehicles to electrical vehicles. Thus, the materials widely used in vehicles as EPP also have to change due to higher requirements in terms of fire properties.In this thesis, three approaches were considered to increase the fire properties of EPP and reach a V0 rating at UL-94 vertical test, according to the three steps of manufacturing EPP. In fact, to manufacture EPP, three steps are necessary: (1) the polypropylene (PP) is melt blended with various additives via an extrusion process, (2) the blended PP is expanded, i.e. an expansion gas is introduced into it to form EPP beads and (3) the EPP beads are then molded into the desired shape. Before investigating the different approaches, the UL-94 vertical test was instrumented in order to obtain more information and have a better understanding in terms of fire properties. The different approaches considered were: (1) incorporating flame retardants and synergists into the PP matrix before expansion, this is the most common approach. This approach was deeply investigated with a comparison between several FRs with different modes of action (intumescent FR, free radical generator, etc), an optimization of the most efficient FRs combination and a study of the influence of industrial manufacturing, especially the expansion step. Indeed, the FRs can disrupt the foaming processability (expansion step), due to the high amount of FRs needed and the fact that FRs can play the role of nucleating agents. Moreover, the mechanism of action of the chosen FRs was studied before and after the expansion step. To counter the complexity of the expansion step in the approach (1), alternative approaches were studied in order to validate others concept. The alternative (2), applying a flame-retardant coating on the EPP beads (before molding) and (3) applying a flame-retardant coating to the molded final piece (EPP bars). However, these approaches have also some drawbacks. Indeed, the EPP has poor adhesion properties because it has no functional groups. Thus, an optimization of a plasma treatment was needed in order to increase the adhesion of EPP. Several flame retardant coatings were applied on the surface and the moldability of the coated EPP beads was studied. Finally, the fire properties at UL-94 vertical test of the molded coated EPP beads and coated EPP bars were studied
Chatenet, Sarah. „An instrumented controlled-atmosphere cone calorimeter to characterize electrical cable behavior in depleted fires“. Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R047.
Der volle Inhalt der QuelleElectrical cable sheaths are the most abundant fire load in nuclear power plants and fire is the most frequent internal aggression (one fire outbreak per year and per nuclear unit in France). A fire is threatening by two means: the heat it releases that may drive a fire growth and the smoke it yields, composed of gases and aerosols, that may be toxic and corrosive and interact with components in the area. At advanced stages, confined fires become oxygen depleted and the combustion regime shifts towards under-ventilated and vitiated combustion with the production of unburnt species leading to a higher threat. To assess the potential hazard of a confined fire, it is then of high importance to quantify the heat release, the gases and the aerosols produced by electrical cable sheaths fires in oxygen depleted conditions. To do so, a bench scale apparatus known as the controlled-atmosphere cone calorimeter (CACC) has been developed. The apparatus has been primarily qualified with PMMA plaques. Representative materials of PVC based electrical cable sheath have been formulated and manufactured in the shape of plaque samples. These materials have been characterized in terms of fire parameters (heat release rate, mass loss rate), evolved gases and evolved aerosols under different oxygen concentrations in under-ventilated conditions thanks to the CACC/FTIR/ELPI coupling. Vitiation lowers the heat release rate and decreases the fuel mass loss rate while under-ventilation increases unburnt species and aerosols production
Chatenet, Sarah. „An instrumented controlled-atmosphere cone calorimeter to characterize electrical cable behavior in depleted fires“. Electronic Thesis or Diss., Université de Lille (2018-2021), 2019. http://www.theses.fr/2019LILUR047.
Der volle Inhalt der QuelleElectrical cable sheaths are the most abundant fire load in nuclear power plants and fire is the most frequent internal aggression (one fire outbreak per year and per nuclear unit in France). A fire is threatening by two means: the heat it releases that may drive a fire growth and the smoke it yields, composed of gases and aerosols, that may be toxic and corrosive and interact with components in the area. At advanced stages, confined fires become oxygen depleted and the combustion regime shifts towards under-ventilated and vitiated combustion with the production of unburnt species leading to a higher threat. To assess the potential hazard of a confined fire, it is then of high importance to quantify the heat release, the gases and the aerosols produced by electrical cable sheaths fires in oxygen depleted conditions. To do so, a bench scale apparatus known as the controlled-atmosphere cone calorimeter (CACC) has been developed. The apparatus has been primarily qualified with PMMA plaques. Representative materials of PVC based electrical cable sheath have been formulated and manufactured in the shape of plaque samples. These materials have been characterized in terms of fire parameters (heat release rate, mass loss rate), evolved gases and evolved aerosols under different oxygen concentrations in under-ventilated conditions thanks to the CACC/FTIR/ELPI coupling. Vitiation lowers the heat release rate and decreases the fuel mass loss rate while under-ventilation increases unburnt species and aerosols production
Dupretz, Renaud. „Synthesis of novel phosphinate flame retardants for poly butylene(terephthalate) (PBT) and polyamide 6 (PA6)“. Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10193/document.
Der volle Inhalt der QuelleThis study deals with the flame retardancy of two engineering plastics, the poly(butylene terephthalate) (PBT) and the polyamide 6 (PA6), widely used in the electrical and electronic equipment (EEE). The focus is made on the incorporation of phosphorus- and nitrogen-containing flame retardant (FR) additives. The main goal of this project was to prepare novel FR through organic synthesis. Five aluminum phosphinates were prepared by reaction of amines on hydroxyphenylphosphnyl propanoic acid and an aluminum promoter. The salts were incorporated to PBT and PA6, with or without co-additives, and the materials were tested in the UL-94, test investigating the vertical propagation of the flame and widely used in the EEE industry. Among the five salts, only the aluminum salt of phenyl amide of hydroxyphenylphosphnyl propanoic acid showed outstanding properties as FR. Other tests were carried out, among which an instrumentation of the UL-94 test, to build a way to the comprehension of mechanisms. First observations were completed by various microanalyses. It has been shown that the decomposition of PAS enhances that of PBT in parallel to its cooling. The liberation of phosphorus-containing species in the gas-phase, despite les efficient than in the case of other commercial FR, gives the formulation its auto-extinguishing character
Dias, de Moraes Poliana. „Influence de la température sur les assemblages bois“. Nancy 1, 2003. http://www.theses.fr/2003NAN10157.
Der volle Inhalt der QuelleThe more generalized use of wood for building raises concern for fire safety. The current standards require the structure stability for a minimum time to ensure the building evacuation and the fire fight. Considering that the fire endurance of wood is well-known, the stability requirement is mainly reduced to the understanding of the behaviour of wood joints on fire. The aim of this work is to study the behaviour of single-dowel timber joints and it is divided into three parts. The first part is a study of the influence of temperature on the modulus of elasticity and on the embedding strength in a range between 20 and 300 °C. In the second part the wood charring and the influence of a metallic dowel embedded in wood, is studied. In the third part, the fire behaviour of single-dowel wood joints is tackled. The first two studies have provided mechanical and thermal data to allow the development of a model to simulate the joint behaviour and its fire endurance before fracture
Samyn, Fabienne. „Compréhension des procédés d'ignifugation du polyamide 6 : apport des nanocomposites aux systèmes retardateurs de flamme phosphorés“. Lille 1, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-Samyn.pdf.
Der volle Inhalt der QuelleBeaugendre, Agnès. „Self-stratifying flame retardant coatings for plastics“. Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10114/document.
Der volle Inhalt der QuelleThis PhD work is a proof of concept on the design of flame retardant (FR) self-stratifying coatings for polycarbonate (PC). This one pot process allows an eco- and smart-development of new products while reducing cost, processing time and solvent emission. In this work, two original self-layering coatings based on epoxy /silicone and /fluoropolymer blends were developed. Their perfect stratification was evidenced using different techniques, in a thickness range up to 130 µm. The influence of solvents characteristics, hardener, curing conditions, fillers and their incorporation phase was studied. Finally, the system diluted in butylacetate: xylene (1:1) leads to the best layering and adhesion, with the thermoplastic phase located on the top of the film. The FR fillers tested (iron oxide, calcium carbonate and two phosphorus based additives) do not affect the layering when introduced up to 10 wt.%. However, visual appearance and adhesion are strongly dependent on the solvent used. The best improvements in terms of FR properties, adhesion and weatherability (temperature, UV, humidity) were obtained by adding micrometric Fe2O3 particles: it allows the formation of a protective barrier which limits substrate/flame mass transfers, and prevents from the yellowing of the system under UV. Although Fe2O3 catalyzes the thermal degradation of the fluorinated resin, the coating reduces flame spread, dripping and slightly promotes the formation of a char. When added to the silicone-based blend, the thermal stability is improved, which allows reducing the combustibility and ignitability of the coated PC. Finally, those properties are relatively maintained after 8 weeks of ageing
Gossiaux, Alexandre. „Comportement au feu de mousses polyuréthanes rigides : Approches systématiques“. Electronic Thesis or Diss., Centrale Lille Institut, 2021. http://www.theses.fr/2021CLIL0021.
Der volle Inhalt der QuelleA common awareness of environmental factors and more particularly of global warming makes it urgent to better control energy consumption. One solution is to reduce energy loss in building using new and efficient thermal insulation materials such as polymeric foams. Polyurethane (PUR) and polyisocyanurate (PIR) foams are very effective and competitive materials due to their low cost. However, these materials are extremely flammable due to their organic nature. Researchers and manufacturers add molecules called flame retardants (FRs) to their composition in order to prevent the outbreak of a fire or reduce the intensity of combustion when a fire breaks out. The objective of this PhD work is to study by systematic approaches the fire behavior of PUR and PIR foams. The aim is to propose a scientific approach allowing a quicker and more efficient development of new formulations. This systematic study was also coupled with a multi-scale study of the fire behavior of the foams, as a laboratory-scale fire test was developed (M-SBI), which allowed a quick and efficient examination of the formulations. The FRs studied in this work are phosphorus organic FRs which are currently promoted to replace some halogenated FRs which could be dangerous for the environment and health. The mechanisms of degradation of virgin and flame retarded foams were elucidated using various analytical tools. Thus, in the case of phosphorus FRs, we were able to demonstrate that their mode of action varied according to the phosphorus oxidation degree as well as according to their point of decomposition. Moreover, the efficiency of the FRs also varies according to the foam used (PUR or PIR). All these results can thus advantageously be exploited to propose future efficient flame retardants for specific systems to reduce the combustion intensity of the foams
Vahabi, Henri. „Combinaison de nanoparticules et de composés phosphonés pour améliorer le comportement au feu du PMMA“. Thesis, Montpellier 2, 2011. http://www.biu-montpellier.fr/florabium/jsp/nnt.jsp?nnt=2011MON20095.
Der volle Inhalt der QuellePoly(methylmethacrylate) (PMMA) is an important thermoplastic, widely used in industry. Unfortunately, it is a highly flammable polymer. The aim of this research was to improve the thermal stability and fire behavior of PMMA. First, we studied the influence of the dispersion of pure or treated kaolin on the fire behavior and thermal stability of PMMA. In second part of this work, the chemical modification of PMMA, using copolymerization of methyl methacrylate (MMA) with two phosphonated co-monomers was studied. Finally, we interested in chemical or physical incorporation of two types of polyhedral oligomeric silsesquioxane particles (POSS) in the PMMA or modified PMMA copolymère (MMA – co- monophosphonated monomer)). The effect of the combination of POSS particles and modified PMMA on the thermal degradation and flammability of PMMA was studied. In our work, the effect of phosphorus in the gas and condensed phase was separately studied. This study allowed us to define an efficiency index of phosphorus in each phase
Giraud, Stéphane. „Microencapsulation d'un diisocyanate et d'un phosphate d'ammonium : application : élaboration d'un systè́me polyuréthane monocomposant à propriété retardatrice de flamme pour l'enduction textile“. Lille 1, 2002. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2002/50376-2002-311-312.pdf.
Der volle Inhalt der QuelleL'incorporation dans une formulation PU de phosphate d'ammonium encapsulé avec une membrane imperméable peut donner un caractère FR permanent à l'enduit. Cette étude est consacrée à la mise au point de procédés de microencapsulation, principalement selon la technique par polymérisation interfaciale, pour l'isophorone diisocyanate (IPDI) et pour le diammonuim hydrogénophosphate (DAHP). Différents paramètres expérimentaux ont étés maitrisés afin de donner aux deux types de microcapsules les caractéristiques déterminantes pou leur application : contrôle de leur taille, de leurs propriétés thermomécaniques et de la perméabilité de leur membrane. Après l'étude de la réactivité d'un mélánge microcapsules d'IPDI - polyol, nous sommes parvenus à synthétiser un PU solide avec une température de réaction peu élevée (80°C). Les microcapsules de DAHP donnent aux enduits PU appliqués sur tissu coton un réel effet retardateur de flamme, même si le char développé avec les microcapsules résiste un peu moins bien à la chaleur que celui avec le DAHP pur
Robert, Fabienne. „Comportement des bétons sous haute température et en cas d’incendie : caractérisation multi-échelle“. Cachan, Ecole normale supérieure, 2008. http://www.theses.fr/2008DENS0046.
Der volle Inhalt der QuelleThe full understanding of concrete structure behavior submitted to fire requires to study the phenomena at different scale, from micro scale to macro scale. The aim of this work is to understand the links between the phenomena observed at different scale. This study investigates the chemical phases’ transformation at high temperature thanks to different means of characterization of the microstructure (XRD, DSC, Environmental SEM …). It has been demonstrated that the increase in compressive strength at 200°C may be due to the formation of Katoite or Jaffeite. Moreover, the major part played by the stress state of the concrete elements on the spalling behaviour, between intermediate and full scale, has been put forward. The full scale tests have been done with Promethee Laboratory, new and innovative testing facility which allows to take into account the interactions during a fire between the tested element and the surrounding cold building. The tested element is as a result in a real mechanical and thermal stress state. This approach is based on a substructuring system. The hydraulic jacks forces will be time dependent and calculated taking into account both the deflected shape and the stiffness matrix of the cold surrounding building
Dorez, Gaëlle. „Formulation et comportement au feu de composites biosourcés“. Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20144.
Der volle Inhalt der QuelleThe environmental awareness in the society is increasing and leads to a strong demand in material from renewable resources, such as biocomposites. The thermal sensitivity and the flammability restrict their use for certain applications such as building. The fire safety regulation is of prime importance and requires adaptive solutions to be found to improve the fire behavior of these materials.In this context, we have studied the thermal degradation and the fire behavior of natural fibers and particularly the effect of its components on the fire behavior. Then, we studied the reactivity of four moieties (amine, carboxylic acid, alkoxisilane and phosphonic acid) on the natural fibers. The grafting characterization was carried out with original techniques based on thermal degradation.Then, we are interested on the thermal degradation and the fire behaviour of biocomposites. We studied the fire behaviour of biocomposite based on PBS and natural fibers varying different parameters such as the amount of fibers, the type of natural fibers and the influence of a phosphonated fire retardant. Two fireproofing strategies have been tested: the addition in polymer matrix and the grafting on natural fibers of fire retardant. To go further in the fireproofing strategy by fire retardant grafting, we have compared the influence of the molecule or macromolecule grafting on the fire behaviour of flax and PBS/flax biocomposite
Gabut, Olivier. „Exploitation et développement du cône calorimétre pour évaluation du comportement au feu de matériaux : application au matériel électrotechnique“. Lille 1, 1998. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1998/50376-1998-453.pdf.
Der volle Inhalt der QuelleTerrei, Lucas. „Comportement au feu du matériau bois : auto-inflammation, dégradation et auto-extinction“. Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0118.
Der volle Inhalt der QuelleThe construction of positive energy and low carbon footprint buildings is a real response to the environmental issues and challenges of the coming decades. An increasing number of high-rise building construction projects made largely of wood are either under study or under construction. A key issue for the construction of such buildings is the fire behavior of these structures. Indeed, when the wood is subjected to a high heat flux, it will degrade and it can self-ignite. Conversely, in certain conditions, wood can self-extinguish. However, the bibliography shows the disparity concerning experimental results for a same material subjected to a given test such as the cone calorimeter. The results on the wood extinction remain limited in view of recent research carried out on this phenomenon. The aim of the thesis is to experimentally study the self-ignition, degradation and self-extinction of the wood material used in buildings. For this, many tests at different scales have been performed to examine the ability of the wood material to self-ignite or self-extinct under prescribed conditions. A total of 600 tests, were performed in vertical orientation and allowed to consolidate results with a statistical approach. A dedicated experimental setup has been deployed on each experimental device studied: an infrared camera providing to measure the surface temperature of the samples when they are subjected to a heat flux, two fast cameras (visible and infrared) in order to record the location and the auto-ignition mechanisms and very thin thermocouples embedded in the wood to measure the temperature evolution in the material according to fixed conditions. Results showed that for the auto-ignition (i.e. without pilot), the notion of ignition temperature of the material could be questionable when the ignition occurs at short times. Indeed, the flame appearance is, in most of the experiments, at a distance far from the exposed surface to the heat flux. The ignition mechanisms do not depend on the surface temperature but on the gas / air mixing conditions as well as the mixture temperature. The auto-ignition surface temperature makes therefore sense only for long auto-ignition times, for which ignition occurs close to the surface. The samples degradation depends on many factors: sample orientation, sample humidity, wood species, oxygen concentration in the atmosphere. The effect of these parameters was considered in this work. A particular attention was focused on the establishment of a metrology aimed at obtaining precise and accurate measurements. Very thin thermocouples, embedded in the sample and oriented parallel to the isotherms allow a better estimation of the temperature and were therefore used. Finally, a new experimental device based on two cones calorimeter arranged on a sliding table system was set up and made it possible to determine simple criteria for wood self-extinguishment at small scale
Goupil, Anne-Charlotte. „Contribution à l'étude numérique du comportement au feu d'un panneau composite pour l'industrie navale“. Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1003/document.
Der volle Inhalt der QuelleStructural panels used in naval industry such as bulkheads and decks must succeed in standard certification testssuch as ISO 834 to be commercialized and settled on board. As these tests are long and expensive, panel manufacturerswish to maximize chances of success for their panels when submitted to certification tests especially when it comes toalternative designs such as composite sandwich panels.Finite elements analyses are used to model thermo-mechanical behavior. Industrial software such as SAMCEF,which was used to conduct this work, are able to solve thermal analyses with degradation and mechanical analyses involvingcontact conditions, degradation of mechanical properties and loss of structures due to failure.The objective in this study is to first identify characteristics of these structures. They are special due to their size andtheir manufacturing. This study aims also to determine thermal and mechanical data required for numerical modeling.When necessary some data can be computed from results coming from the results of the materials’ reaction to fire.Numerical models are developed to determine thermo-mechanical behavior and are designed to be robust and used inindustrial context. They include the evolution of thermal and mechanical properties during the degradation process. Thesemodels must enable to estimate the performances of innovative designs during an ISO 834 certification test
Russo, Patrice. „Simulation numérique aux grandes échelles de la propagation du feu, en espace ouvert et confiné, représentative des incendies d'entrepôts“. Poitiers, 2005. http://www.theses.fr/2005POIT2292.
Der volle Inhalt der QuelleThe objective of this work is to improve the understanding of fire spread at large scales within the rack storage in warehouses. The numerical tool used is FDS (Fire Dynamics Simulator), modified for the present case. It is based on the resolution of the Navier-Stokes equations appropriate for low Mach number and of the conservation equations of energy, mass and species. A mixture fraction model with infinitely fast chemistry schema is used for simulating the combustion. The equation of radiative transfer and a pyrolysis model obeying a simple Arrhenius relation are also been incorporated. The standard sub-grid scale model (Smagorinsky's model) is adopted in the LES (Large Eddy Simulator). At first, FDS is validated by comparing results from experiments of fires carried out in open and in confined spaces. This makes it possible to predict the principal characteristics of fire, such as the flame height above the top of the rack, the flame propagation rate, the radiative and convective fluxes. . . A preliminary study, based on the simulation of an area of a warehouse, determines the parameters supporting the progression of fire among the racks such as the height of the ceiling. Finally, the simulation of a whole warehouse under various configurations, provides detail informations (powers released by the fire. . . ) on the way a fire is propagates in the presence of a large number of racks
Mandlekar, Neeraj Kumar. „Integration of wood waste to develop multifunctional fully biobased textile structure“. Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I062/document.
Der volle Inhalt der QuelleIt has been chosen to study valorization of low-cost industrial lignin as additive in designing the flame retardant (FR) system for polyamide 11 (PA) to develop biobased textile structure. The main focus of this thesis work is to consider lignin as carbon source and introduce in a textile structure in combination with phosphinate salt (FR agent). In the primary study, chemically different industrial lignins were incorporated in PA by extrusion to investigate the charring and fire retardant behaviour of the prepared binary blends. In addition, the introduction of sulphonated lignins significantly reduced the peak of the heat release rate (PHRR) and of the total heat release (THR), and a noticeable increase of the char residue was observed after forced combustion test. In the next approach, lignin was exploited as carbon source in combination with commercially available phosphinate FR (i.e., ZnP and AlP). To achieve this objective, a preliminary study carried out with laboratory grade lignin (LS) combined with ZnP to investigate the thermal stability and fire performance as well as the possible synergy between lignin and ZnP and with the polymer matrix. The results obtained in this study permitted to continue further, the practical implementation of lignin and multifilament production. In the next step, flame retarded blends were developed with direct addition of low-cost industrial lignins (LL and DL) with phosphinate FR. For the systematic understanding, various FR formulations were developed by varying the lignin and FR loading and characterized. Thermal decomposition analysis showed that the presence of lignin decreases the initial decomposition temperature (T5%) due to the decomposition of lignin which starts at a lower temperature region with the evolution of less thermally stable compounds and the maximum decomposition temperature (Tmax) shifts to higher temperature region, at this stage the formation of phenolic, carbonyls, hydrocarbons and CO2 along with phosphinate compounds occurs. Meanwhile, in the condensed phase thermally stable aromatic charred layer is formed because of lignin decomposition and phosphate compounds formation due to the presence of phosphinate metal salt. A higher amount of char residue is obtained when LL combined with ZnP/AlP as compared to the DL and ZnP/AlP blends. It is assumed that, during decomposition of LL, the sulfonate compounds release SO2 and transformed into thermally stable Na2SO4, hence giving rise to the stable char residue. The fire properties were assessed by cone calorimeter tests revealed the combination of lignin and phosphinate FR significantly reduced the PHRR and other fire-related parameters due to the formation of a protective char layer. The presence of lignin not only improve fire retardancy but also reduced the evolution of carbon monoxide (CO). More enhanced fire retardant properties were obtained with LL and ZnP/AlP combination reaches to 10 wt% in ternary blends, which not only promotes char formation but also confer the stability to char in the condensed phase. Furthermore, the most enhanced forced combustion results were obtained with LL and AlP (in particular, PA80-LL10-AlP10). Multifilament yarns were successfully produced for PA-DL-ZnP and PA-LL-ZnP combinations. However, the blends of AlP with lignin were not spinnable because of low compatibility and dispersion level of AlP in the polymer. Optical microscopy and tensile tests were performed to study the physical properties of multifilaments. A double layer (interlock structure) knitted fabrics were developed to evaluate fire behaviour analysis on fabric samples
Hu, Chi. „Flame retardancy of polybutylene succinate by multiple approaches“. Thesis, Lille, 2018. http://www.theses.fr/2018LIL1R073.
Der volle Inhalt der QuelleThis study was dedicated to the development of flame retarded polybutylene succinate (PBS), a bio-based polymer, which possess good mechanical properties and biodegradability, by various different approaches. In this context, modifications of isosorbide were achieved to obtain bio-based flame retardants. Then isosorbide and poly(isosorbide) carbonate (PIC) were blended with PBS and APP to form intumescent flame retardant system acting as carbonization agent. It shows the improvement of the flame retardant properties in the condensed phase where the yield of residual char was increased and the pHRR and THR were decreased. A conventional flame retardant, DOPO, showed some super flame retardant property for PBS in the gaseous phase. It had an improvement of the ignition time from 119 s to 410 s in MLC test when 10 wt% of DOPO was incorporated in PBS. An original UL-94 instrumentation was designed to investigate its mode of action during a fire scenario. These studies have provided the information for the future works on flame retardancy of bio-based polymers
Ngohang, Franck Estimé. „Combination of mass loss cone, Fourier transforminfrared spectroscopy and electrical low pressure impactor to extend fire behaviour characterization of materials“. Electronic Thesis or Diss., Lille 1, 2014. http://www.theses.fr/2014LIL10167.
Der volle Inhalt der QuelleA bench-scale test combining mass loss cone, Fourier transform Infrared Spectroscopy and Electrical Low Pressure Impactor (MLC/FTIR/ELPI) was developed to enable simultaneous evaluation of the flammability parameters, the gases evolved (qualitative and quantitative evaluation) and the smoke particles (size distribution and concentration) generated by the combustion of the studied materials. This bench test is designed specifically to investigate the fire behaviour of manufactured products such as electric cables, as it is difficult to fully examine the latter with bench tests of the type thermogravimetry or pyrolysis - gas chromatography/mass spectrometry, which can only hold small quantities of sample (from µg to a few mg). After setting up the MLC/FTIR/ELPI coupling, methodologies were established for qualitative and quantitative analysis of evolved gases and smoke particles. Experimental trials conducted on ethylene vinyl acetate (EVA) and ethylene vinyl acetate/aluminium trihydroxide (EVA/ATH) as reference materials demonstrated that the bench test provides accurate, meaningful and repeatable results