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Armand, Decker Stéphanie. "Développement d’une méthode d’optimisation multiobjectif pour la construction bois : prise en compte du confort des usagers, de l’impact environnemental et de la sécurité de l’ouvrage". Electronic Thesis or Diss., Bordeaux, 2015. http://www.theses.fr/2015BORD0189.
Pełny tekst źródłaIndustrialised countries are seeking to reduce their energy consumption and to use alternative raw materials, including renewables such as wood. To promote its use, multi-storey timber constructive systems need the development of new design methods.Building required a multicriteria design where conflicting objectives must be optimised simultaneously. Research solutions have to achieve the best Pareto-compromise between use performance and environmental impact of the building. This work aims to develop a multiobjective optimisation method of timber multi-storey building.The objectives of maximising floor vibration comfort and minimising heating needs, thermal discomfort, global warming potential and embodied energy are taken into account. A multi-objective particle swarm optimization algorithm is used to obtain a set of non-dominated solutions which is the Pareto front. The solution space is constrained by regulatory requirements necessary for the safety of the structure. All objective-functions are modelled as analytic functions. Dynamic thermal simulation model outputs are replaced by metamodels.The developed method is implemented on a case study. The results offer a great diversity in a panel of 20 000 optimal solutions. These results provide a basis for discussion between the different actors of a construction project
Raji, Saed. "Caractérisation hygro-thermique, par une approche multi échelle, de constructions en bois massif en vue d'amélioration énergétique et de valorisation environnementale". Bordeaux 1, 2006. http://www.theses.fr/2006BOR13335.
Pełny tekst źródłaDeuffic, Philippe. "Produire et discuter des normes environnementales : écologues et forestiers face à la biodiversité associée au bois mort". Phd thesis, Bordeaux 2, 2012. http://tel.archives-ouvertes.fr/tel-00842846.
Pełny tekst źródłaYoussef, Alice. "Prise en compte des apports mécaniques du béton de chanvre pour le calcul de structure bois/béton de chanvre et métal/béton de chanvre". Electronic Thesis or Diss., Lorient, 2017. http://www.theses.fr/2017LORIS431.
Pełny tekst źródłaLime and hemp concrete (LHC) is nowadays the most developed bio-based aggregate building material in Europe. It consists of hemp shiv and mineral binder mixing with water. Generally, bio-based materials like LHC are used for their thermal insulation properties in building. Most blocks of Lime Hemp Concrete which have been studied, show a brittle behavior and a very low mechanical strength. The formulations are generally rich in binder and slightly compacted. Up to now, this material is then not considered as a load bearing material and is mainly used as filler insulation, combined with structure components made of wood, concrete or masonry. A study has tested other formulations, with higher contents of aggregates thanks to a compaction process, in order to improve both the rigidity and the strength of the hardened mixtures. In these formulations, shiv which has higher amount is definitely lighter and more porous than lime, which prevents a significant increase in thermal conductivity. The present work of my PhD is an experimental study of the compressive and shearing behavior of hemp concrete, in order to study the load-bearing capacity and bracing of this bio based material, while maintaining good qualities of thermal insulation in building. Two compacted formulations were tested M1 & M4, as well as samples obtained from trade-blocks Chanvribloc®. Two series of tests were performed. The first one is a uniaxial compression test in each direction for characterizing the mechanical anisotropy of the material. This anisotropy is induced by the compacting process. The second one permits to characterize the shearing behavior of the different mix-designs. In this study, an original shear device was developed, specifically designed for this kind of material, which allows shearing under controlled normal stress. An image processing performed was carried out, using a camera and ARAMIS image processing software during shear tests, to evaluate the fields of deformations and to study the behavior of the specimen during the shear test. The compressive experiments results have shown that this material is anisotropic, even when it is industrially molded by vibrations. The material has a transverse isotropic behavior. The behavior in the longitudinal direction is characterized by very high ductility, while the transverse behavior is very brittle, with a highly variable and unsteady behavior. The experimental results in shear show a high ductility of this material. These results are very promising, an interesting behavior of LHC walls in term of potential bracing. Numerical modeling and applications have been carried out to illustrate the use of hemp concrete blocks for bracing buildings. The formulation M4 exhibits a better behavior under moderate and average seismic actions, compared to the formulation M1, while the Chanvribloc walls in the present state do not allowthe buildings to be braced in moderate or medium seismic zones
Tlijani, Mohamed. "Contribution à la caractérisation thermophysique de matériaux bio-isolants : valorisation des déchets de bois de palmier". Electronic Thesis or Diss., Paris Est, 2016. http://www.theses.fr/2016PESC1157.
Pełny tekst źródłaThe growing interest in new concrete and their use in many fields of civil engineering was that we wanted to bring a new approach to the design of a new product consisting of a reinforced concrete with basel end frond palm fibers. This led us to conduct the experimental study of thermal properties of natural fibers of date palm (Phoenix dactylifera L.). The analysis of experimental results showed that the essential factors affecting the thermal conductivity are the variety of date palm and the fiber orientation and that the basel end of the frond palm is the most interesting part as thermal insulation. However, the main problem encountered when using plant fibers as reinforcement is cohesion, bonding with the matrix and dimensional instability so the composite loses its mechanical properties. In this context, an alkaline pretreatment of palm fibers was envisaged to clean and modify the fiber surface to address the problems of dimensional stability of the fibers and degradation before their use as reinforcement in the cement matrix. We also studied the influence of chemical treatment with sodium hydroxide on the mechanical properties of processed samples, they were subjected to the tensile test to estimate the fracture strength for each treatment concentration, the Young's modulus and elongation at break corresponding. Subsequently, we conducted experimental and theoretical research on the thermal conductivity of different formulations of basel end palm wood concrete composite. The study of the theoretical apparent thermal conductivity was based on an approach that relies on a process whereas the material consists of a solid matrix combined with a fluid phase (air). Finally, we performed a numerical simulation of heat transfer phenomena to assess the thermal conductivity of basel end frond palm concrete composite and validate subsequently the theoretical prediction model selected. The results showed that the numerical approach based on the isotropic orientation of the particles in the composite coincides and approaches the physical reality
Armand, Decker Stéphanie. "Développement d’une méthode d’optimisation multiobjectif pour la construction bois : prise en compte du confort des usagers, de l’impact environnemental et de la sécurité de l’ouvrage". Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0189/document.
Pełny tekst źródłaIndustrialised countries are seeking to reduce their energy consumption and to use alternative raw materials, including renewables such as wood. To promote its use, multi-storey timber constructive systems need the development of new design methods.Building required a multicriteria design where conflicting objectives must be optimised simultaneously. Research solutions have to achieve the best Pareto-compromise between use performance and environmental impact of the building. This work aims to develop a multiobjective optimisation method of timber multi-storey building.The objectives of maximising floor vibration comfort and minimising heating needs, thermal discomfort, global warming potential and embodied energy are taken into account. A multi-objective particle swarm optimization algorithm is used to obtain a set of non-dominated solutions which is the Pareto front. The solution space is constrained by regulatory requirements necessary for the safety of the structure. All objective-functions are modelled as analytic functions. Dynamic thermal simulation model outputs are replaced by metamodels.The developed method is implemented on a case study. The results offer a great diversity in a panel of 20 000 optimal solutions. These results provide a basis for discussion between the different actors of a construction project
Lupsea, Maria-octavia. "Contribution to the environmental impact assessment of buildings : numerical modelling of dangerous substances’ release to water". Electronic Thesis or Diss., Toulouse, INSA, 2013. http://www.theses.fr/2013ISAT0007.
Pełny tekst źródłaAny construction product and building undergoing contact with water during its life cycle can release chemical compounds potentially hazardous for the human health and the environment. The release of dangerous substances is presently investigated especially by experimental approaches commonly by laboratory leaching tests while the environmental impacts of construction products and buildings are evaluated by a Life Cycle Assessment (LCA) approach. The dangerous substances release during use stage of construction products (leaching behaviour) is currently very poorly represented in the existing data bases and methods for environmental assessment of construction products and buildings.In this context, the main objectives of this study were: (i) to develop a methodology for the assessment of the leaching behaviour of various construction products and (ii) to integrate the leaching data in LCA approach at building scale. The methodology developed for the assessment of the leaching behaviour of construction products is based on: (1) characterisation leaching tests at lab scale, following the horizontal standardised assessment methods for harmonised approaches relating to dangerous substances under the Construction Products Regulation (CPR), (2) modelling and simulation of coupled chemical and transport phenomena at lab and field scale, and (3) utilisation of simulated leaching data for the construction products exposed in natural condition with the LCA method for the characterization of the hazardous effect during the use stage. The proposed methodology was applied and validated on three different classical construction products i.e. CBA (Copper-Boron-Azole) treated wood, fibre-cement sheets and bitumen membranes. The leaching behaviour of CBA treated wood and fibre-cement sheets was simulated over several years under natural exposure conditions, using the geochemical software PHREEQC. The chemical models consider both the mineral and the organic matrixes and their interaction with treatmentcompounds. Mass transfer and transport phenomena were modelled. The developed coupled chemical-transport models are able to represent the dynamic leaching behaviour of the respective products in various leaching conditions. For bitumen membranes only experimental characterisation was possible. The leaching data obtained by simulation over the whole use stage of the products were integrated in the life cycle inventory (LCI) and the relevant life cycle impact assessment (LCIA) methods were applied with the enriched inventory. A simplified single-family house was modelled using a software designed to evaluate the intrinsic environmental performances of a building over its entire life cycle. ELODIE software was used in this work. The building scale assessment methodology is based on coupling the methodology developed for the product scale with the Life Cycle Assessment (LCA) at building scale. This methodology allows a proper integration of leaching data in LCA tools and answers several technical questions raised in the field
Watchman, Mélanie. "Bois et confort environnemental : l'importance de la matérialité dans l'évaluation post-occupationnelle". Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/28066.
Pełny tekst źródłaMany environmental advantages of wood in buildings have been thoroughly documented; however this material’s effects on occupants are not well known and fully comprehended. Previous studies have demonstrated that factors unrelated to the indoor environment quality can affect comfort, but the influence of materiality is seldom considered. This research focused on studying occupant comfort in a multifunctional room characterised by extensive wood surfaces in comparison with a similar room with more conventional surfaces at Laval University, Quebec, Canada. The objectives of this research focus on better understanding how occupants perceive wood in built environments, determining the thermal, visual, acoustical and olfactory similarities and differences between two rooms using on-site surveys and exploring whether the indoor use of wood influences occupant comfort. A comparative study within a post-occupancy evaluation framework analysed the subjective perception of building occupants in relation to physical comfort factors. A total of 36 occupants completed a questionnaire elaborated to compare comfort satisfaction between two rooms with different interior finishes. Analysis of instrumental measurements and images of each room’s indoor environment determined the similarities and differences between the rooms. Quantitative and qualitative analyses reveal that both rooms share similar thermal and acoustic comfort parameters, but present contrasting visual characteristics. The colour, knots and grain of the wood contributed to visually warm experiences resulting in a yellowish room whereas a mix and match of artificial finishes generated a colder, bluish ambiance in the other room. Results from the questionnaire indicate that occupants were generally more satisfied in the room with extensive wood surfaces in terms of lighting, noise and temperature despite objectively similar environmental conditions in both rooms. The conclusion reached is that architects should consider the indoor use of wood for its unique visual ambiances that enhance comfort levels.
Merakeb, Seddik. "Modélisation des structures en bois en environnement variable". Limoges, 2006. https://aurore.unilim.fr/theses/nxfile/default/94578804-9926-46e0-8969-67a4656612ce/blobholder:0/2006LIMO0031.pdf.
Pełny tekst źródłaMechanical properties of timber constructions depend strongly on moisture content state. In this context, it is shown a mecanosorptive coupling. This climatic environment aspect imposes a hygroscopic behavior modeling in order to estimate moisture content variations by integrating the heat and mass transfer processes. If the effect of moisture content on the mechanical behavior has been studied in the literature, this work enables us to precise effects of mechanical state on the transfer laws by taking into account boundary conditions and diffusion properties. In this context, we propose a thermodynamic and experimental approaches which allow to introduce a realistic coupled transfer algorithm in a finite element software
Richard, Nicolas. "Approche multi-échelles pour la modélisation de structures en bois sous sollicitations sismiques". Cachan, Ecole normale supérieure, 2001. http://www.theses.fr/2001DENS0010.
Pełny tekst źródłaBoulet, Sylvain. "Caractérisation du confort hygrothermique et acoustique dans les constructions à base de bois". Chambéry, 2009. http://www.theses.fr/2009CHAMS047.
Pełny tekst źródłaThe use of wood for building improves sustainability and achieves high acoustic and thermal performance. Wood is often used for design of energy efficient buildings either in recent building or for refurbishment. Besides the low energy consumption, there are many positive testimonies of occupants about general comfort. Nowadays, the various comfort approaches are essentially or thermal or acoustical, but the impact of one on the perception of the other one is important and must be taken into account. Measurements and subjective enquiries do not allow concluding about the positif contribution of wood for comfort, but must provide arguments to give good reason for the use of wood in buildings applications. The objective of the presented study is the identification of parameters affecting thermal and acoustical comfort in moderate environment. We present qualitative and quantitative full-scale analysis of in-situ measurements. A first step, we introduce the methodology of measurement and enquiries. Then we present the analysed house determined with a Taguchi "design of experiments". We analyse results through the multicriteria decision analysis. And confrontation between measurements and inquiries will be realized in case of validation. Finally, we focus on summer thermal comfort, we proceed to a characterisation of indoor environment by numerical simulation to study various factor influence on summer thermal comfort
Ultré, Pierre. "Analyse critique et optimisation d'un processus de production d'éléments préfabriqués en bois". Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/33041.
Pełny tekst źródłaCurrently, industrialized housing is facing an increased demand while a lot of small producers have to deal with a lack of capacity and non-automated production processes. This master thesis focuses on the way to improve the production processes in this field in order to gain efficiency. First, a literature review leads to a comprehensive state of the art concerning scheduling and production management practices in industrialized housing. It compares this sector to the traditional construction field and the manufacturing industry. It then identifies the various problems enterprises may face while suggesting potential solutions. Thereafter a case study involving a company specialized in producing prefabricated elements is studied in detail. The focus is on the processes conducted to manufacture panels. Improvements that should be implemented in order to decrease operation times as well as better use the production capacity while respecting the labor’s availability constraint are proposed. A simulation model is therefore developed to test those suggestions and to evaluate the gain each solution can generate so as to meet a rise in demand. Results show that the most interesting improvements are those involving to invest in automation technologies.
Lupsea, Maria-octavia. "Contribution to the environmental impact assessment of buildings : numerical modelling of dangerous substances’ release to water". Thesis, Toulouse, INSA, 2013. http://www.theses.fr/2013ISAT0007/document.
Pełny tekst źródłaAny construction product and building undergoing contact with water during its life cycle can release chemical compounds potentially hazardous for the human health and the environment. The release of dangerous substances is presently investigated especially by experimental approaches commonly by laboratory leaching tests while the environmental impacts of construction products and buildings are evaluated by a Life Cycle Assessment (LCA) approach. The dangerous substances release during use stage of construction products (leaching behaviour) is currently very poorly represented in the existing data bases and methods for environmental assessment of construction products and buildings.In this context, the main objectives of this study were: (i) to develop a methodology for the assessment of the leaching behaviour of various construction products and (ii) to integrate the leaching data in LCA approach at building scale. The methodology developed for the assessment of the leaching behaviour of construction products is based on: (1) characterisation leaching tests at lab scale, following the horizontal standardised assessment methods for harmonised approaches relating to dangerous substances under the Construction Products Regulation (CPR), (2) modelling and simulation of coupled chemical and transport phenomena at lab and field scale, and (3) utilisation of simulated leaching data for the construction products exposed in natural condition with the LCA method for the characterization of the hazardous effect during the use stage. The proposed methodology was applied and validated on three different classical construction products i.e. CBA (Copper-Boron-Azole) treated wood, fibre-cement sheets and bitumen membranes. The leaching behaviour of CBA treated wood and fibre-cement sheets was simulated over several years under natural exposure conditions, using the geochemical software PHREEQC. The chemical models consider both the mineral and the organic matrixes and their interaction with treatmentcompounds. Mass transfer and transport phenomena were modelled. The developed coupled chemical-transport models are able to represent the dynamic leaching behaviour of the respective products in various leaching conditions. For bitumen membranes only experimental characterisation was possible. The leaching data obtained by simulation over the whole use stage of the products were integrated in the life cycle inventory (LCI) and the relevant life cycle impact assessment (LCIA) methods were applied with the enriched inventory. A simplified single-family house was modelled using a software designed to evaluate the intrinsic environmental performances of a building over its entire life cycle. ELODIE software was used in this work. The building scale assessment methodology is based on coupling the methodology developed for the product scale with the Life Cycle Assessment (LCA) at building scale. This methodology allows a proper integration of leaching data in LCA tools and answers several technical questions raised in the field
Koumbi, Mounanga Thierry. "Tensioactifs antioxydants originaux pour la formulation de produits de préservation du bois". Electronic Thesis or Diss., Nancy 1, 2008. http://www.theses.fr/2008NAN10084.
Pełny tekst źródłaThe presented work concerns the synthesis and characterization of amphipilic antioxidant compounds for the formulation of wood preservatives allowing the preparation of waterborne formulations to reduce rejections of VOCs answering to increasing environmental pressures. Based on preliminary studies showing synergistical effects between fungicides and antioxidants, the aim of this study was to design compounds possessing surfactant and antioxidant properties allowing the formulation in water of insoluble organic fungicides and to reduce the necessary quantity of biocide due to synergistical effects with antioxidant properties. Three families of amphiphilic compounds were synthesized. The first one corresponds to hindered phenol derivatives, the second to hindered amine and the third one to quats “with green label” derived from ascorbic acid. Surfactant and antioxidant properties of all new synthesized compounds have been characterized. The use of aqueous formulations of propiconazole prepared from these new surface active agents allows to increase beech wood durability exposed to the white rot fungus Coriolus versicolor. Fungal growth inhibition tests realized on malt agar medium with various alkylammonium ascorbates presenting different alkyl chain’s lengths indicated an important growth inhibition of the mycelium for some of the tested products correlated at their amphiphilic properties
Lebatteux, Muriel. "Durée de vie de poutres en bois reconstitué soumises à un environnement climatique naturel". Bordeaux 1, 1997. http://www.theses.fr/1997BOR10555.
Pełny tekst źródłaPelletier, Chloé. "Analyse environnementale et économique des filières bois-énergie". Electronic Thesis or Diss., Université de Lorraine, 2017. http://www.theses.fr/2017LORR0331.
Pełny tekst źródłaThe objective of this thesis is to conduct the environmental and economic analysis of several wood-to-energy production chains based on various wood combustion technologies. The material and energy balances of the production chains are determined with modeling of forest growth and of wood combustion. The wood combustion models use the emission factors from real-scale experimental tests on stoves and boilers. Forest growth is modeled for maritime pine and beech plantations, according to several forest management schemes. The data on the harvest, transformation, and transport steps, as well as the economic data, were taken from the literature. The environmental analysis compares the impacts calculated by two methods: ReCiPe and CML 2001. A dynamic analysis of the “climate change” impact complements the discussion on the environmental impacts of energy wood. Finally, we open a broader perspective with modeling of land use and production costs of bioenergy on a global scale. The results of the Life Cycle Analysis show the importance of both combustion quality (linked to combustion technology), and the transformation and transport steps. For instance, pellet stoves and boilers have excellent efficiencies, but suffer from the consumption of fossil fuels to dry the biomass. These technologies are also much more expensive to buy than log stoves or boilers. The dynamic analysis shows that the intensification of wood production via the shortening of growth cycles leads to higher impacts that are not completely offset by the higher production rate
Côté, Nelson. "Potentiel de récupération de composantes de fermes de toit dans les sciages flacheux produits en scierie : étude de cas". Doctoral thesis, Université Laval, 2013. http://hdl.handle.net/20.500.11794/25556.
Pełny tekst źródłaDubois, Courau Anne-marie. "Éléments de spécification d'un environnement avancé de modélisation et simulation : application à la thermique du bâtiment". Nice, 1990. http://www.theses.fr/1990NICE4437.
Pełny tekst źródłaPelletier, Chloé. "Analyse environnementale et économique des filières bois-énergie". Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0331/document.
Pełny tekst źródłaThe objective of this thesis is to conduct the environmental and economic analysis of several wood-to-energy production chains based on various wood combustion technologies. The material and energy balances of the production chains are determined with modeling of forest growth and of wood combustion. The wood combustion models use the emission factors from real-scale experimental tests on stoves and boilers. Forest growth is modeled for maritime pine and beech plantations, according to several forest management schemes. The data on the harvest, transformation, and transport steps, as well as the economic data, were taken from the literature. The environmental analysis compares the impacts calculated by two methods: ReCiPe and CML 2001. A dynamic analysis of the “climate change” impact complements the discussion on the environmental impacts of energy wood. Finally, we open a broader perspective with modeling of land use and production costs of bioenergy on a global scale. The results of the Life Cycle Analysis show the importance of both combustion quality (linked to combustion technology), and the transformation and transport steps. For instance, pellet stoves and boilers have excellent efficiencies, but suffer from the consumption of fossil fuels to dry the biomass. These technologies are also much more expensive to buy than log stoves or boilers. The dynamic analysis shows that the intensification of wood production via the shortening of growth cycles leads to higher impacts that are not completely offset by the higher production rate
Figueroa, Adolfo. "Le bois comme matériau de construction : une alternative au problème de concentration urbaine au Venezuela". Bordeaux 3, 1987. http://www.theses.fr/1987BOR30033.
Pełny tekst źródłaVenezuela through its historical and geographical evolution presents urban concentration of its population. Wood used as material construction is considered as a solution to the housing problem
Manthey, Manuel. "Comportement des poutres mixtes bois-béton sous sollicitations accidentelles". Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0034.
Pełny tekst źródłaTimber - concrete composite structures are competitive technical solutions for new building construction as well as in refurbishment. This work aims at promoting timber - concrete construction in France thanks to a better knowledge of mechanical and thermo-mechanical behavior of the fasteners. Regarding more traditional buildings systems, few researches were lead about seismic and fire design of timber concrete structures. Particular emphasis is put on those two points in this study through experimental, analytical and numerical approaches. As a matter of fact, several experimental campaigns were lead. 24 Push Out tests have been carried out at ambient temperature on the SBB timber-concrete composite system. The test program involved 12 Push Out tests under cyclic loading and 12 Push Out tests under monotonic loading. Experimental results brought to light the good mechanical performances as well as the large ductility reserve of SBB timber-concrete connection system. The cyclic tests have revealed the system ability to dissipate energy and allowed quantifying the loss of rigidity and resistance of the system. Descriptive models (Foschi, Dolan, Richard) have been adapted to reproduce to the experimental load-slip curves.In order to get further insight into the local phenomenon taking place between timber and the SBB connector, a second test program was devised. The tests involved 16 Pull Out tests (connector from timber) and 3 series of 16 embedment tests og various parts of the connector in glue laminated timber. Thanks to these experimental results, a better understanding of the SBB behavior has been reached. Predictive models are provided for numerical and analytical modeling of timber - concrete fasteners. Those models show good agreement with the Push Out tests introduced in previous part.In order to assess the fire behavior of timber - concrete composite floor system with the SBB connection system, fire tests were conducted according to ISO 834 standard. Fire results database with SBB timber - concrete connection includes a full-scale fire floor test (floor dimensions are 5.35m x 3.5m) and several fire Push Out tests based on three different timber - concrete composite beam sections. Fire Push Out tests were heavily instrumented with thermocouples in order to allow the validation of thermal models developed in this thesis.Thermal and thermomechanical coupled simulations were conducted with finite element software Abaqus©. These models demonstrate the good performances of timber-concrete composite structures subjected to fire. Heating of the elements and loss in shear resistance and stiffness of the connection system were quantified. Furthermore fire design rules are proposed for timber - concrete structures. Fire behavior analysis pointed out that thermal dilatation of concrete must be considered in fire design of timber-concrete composite structures
Tremblay-Auclair, Jean-Philippe. "Développement d’une méthode de calcul parasismique pour les bâtiments multiétagés à ossature légère en bois". Master's thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/26757.
Pełny tekst źródłaThe main objective of the research project is to develop a seismic design methodology for mid-rise multi-storey light-frame wood structure. Currently, linear dynamic analysis (LDA) is rarely used in design of light-frame wood structures because of the complexity of modelling the non linear behaviour. Equivalent static force procedure (ESFP) is mostly used because of its simplicity. The study is based on a recently developed methodology using an iterative process to simulate non linear behaviour of light-frame wood structure in LDA. In the proposed methodology, the iterations are eliminated by using the minimum shear stiffness of shear walls. To validate the proposed simplification, shear force distributions, overturning moments, interstorey drifts and total inelastic deflections of shear walls with different aspect ratios, from 0.6 to 6.0, in six-, four- and two-storey buildings located in Quebec City were calculated and compared against the results obtained with iterative LDA and with ESFP. The results show that ESFP underestimates the storey shear at the top floor and overestimates the overturning moment at the base of a multi-storey light-frame wood structure in comparison with LDA. The results show that the simplified LDA can be used to optimize the design of mid-rise light-frame wood shear walls.
Kouyoumji, Jean-Luc. "Caractérisation des parois courantes et des liaisons structurales pour la prévision de l'isolement acoustique d'une construction en bois". Chambéry, 2000. http://www.theses.fr/2000CHAMS024.
Pełny tekst źródłaBlondin, Frédéric, i Frédéric Blondin. "Caractérisation du risque incendie de la paille compressée comme isolant d'une structure en bois". Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/34458.
Pełny tekst źródłaDe nombreux programmes de construction écologique ont vu le jour depuis la dernière décennie visant à promouvoir la construction de bâtiments plus durables. Considérant que les matériaux biosourcés peuvent aider à réduire l’empreinte environnementale des bâtiments, il est judicieux d’en étendre leur utilisation. Un récent engouement s’est créé pour les sous-produits de culture céréalière en guise de remplacement aux fibres isolantes non renouvelables dans les structures en bois. De nombreux chercheurs ont étudié certaines isolations naturelles alternatives utilisées de nos jours. En comparaison aux matériaux d’isolations commerciaux, ces matériaux ont un impact environnemental remarquablement faible. Dans cette optique, l’utilisation de la paille compressée comme isolant offre un très faible impact dans l’analyse de son cycle de vie. Cependant, la sécurité incendie a toujours été une grande préoccupation pour les constructeurs utilisant des matériaux naturels combustibles. L'objectif de cette étude est de documenter le risque incendie de la paille compressée lorsqu'elle est utilisée comme matériau isolant dans des assemblages à ossature en bois. Trois densités de paille comprimée (75, 125 et 175 kg/m3) ont été sélectionnées pour évaluer leurs propriétés de combustion et leur conductivité thermique, en essayant de déterminer laquelle avait la meilleure combinaison de propriétés. La paille de la densité sélectionnée a ensuite été comparée aux matériaux d'isolation combustibles disponibles sur le marché pour comparer leur risque d'incendie. Par la suite, cet isolant de même densité a été testé dans un assemblage à ossature en bois à moyenne échelle pour évaluer l'impact de sa charge combustible comparativement à un matériau d'isolation incombustible. Les résultats ont démontré que la paille compressée d'une densité de 75 kg/m3 avait les meilleures propriétés de combustion et d'isolation. Les résultats suggèrent que la paille compressée aurait très probablement un meilleur comportement au feu par rapport à ceux des matériaux d'isolation combustibles disponibles sur le marché. Malgré la nature combustible de la paille compressée, l'impact de sa charge combustible dans un système de construction en bois a été moins important que prévu. Les propriétés de combustion de la paille compressée étant moins dangereuses que les matériaux d'isolation combustibles disponibles sur le marché, ainsi que l'impact de sa charge calorifique dans une structure à ossature de bois, l'utilisation de ce matériau comme isolant principal dans un bâtiment est, par bonne conception, gérable sans augmenter les risques
Many green building programs have emerged since the last decade to promote the construction of more sustainable buildings. Considering those biobased materials can help reduce the environmental footprint of buildings, it is wise to expand their use. A recent craze has emerged for cereal crop byproducts as a substitute for nonrenewable insulation fibers in wood structures. Many researchers have studied some of the alternative natural insulation materials used today. Compared to commercial insulation materials, these materials have a remarkably low environmental impact. In this context, the use of compressed straw as insulation offers a very low impact in the analysis of its life cycle. However, fire safety has always been a big concern for builders using natural combustible materials. The objective of this study is to document the fire hazard of compressed straw when it is used as an insulating material in wood frame assemblies. Three compressed straw densities (75, 125 and 175 kg/m3) were selected to evaluate their combustion properties and thermal conductivity, in attempt to determine which had the best combination of properties. The selected density straw was then compared to commercially available combustible insulation materials to compare their fire risk. Subsequently, this same density straw was tested in a medium-scale wood frame assembly to evaluate the impact of its fuel load comparatively to a non-combustible insulation material. The results showed that compressed straw with a density of 75 kg/m3 had the best properties of combustion and insulation. The results suggest that compressed straw would most likely have better fire performance compared to combustible insulation materials available on the market. Despite the combustible nature of the compressed straw, the impact of its fuel load in a wooden construction system was less than expected. Because the burning properties of compressed straw are less hazardous than commercially available combustible insulation materials and the impact of its heat load in a wood frame structure, the use of this material as an insulator in a building is, by design, manageable without increasing risks.
Many green building programs have emerged since the last decade to promote the construction of more sustainable buildings. Considering those biobased materials can help reduce the environmental footprint of buildings, it is wise to expand their use. A recent craze has emerged for cereal crop byproducts as a substitute for nonrenewable insulation fibers in wood structures. Many researchers have studied some of the alternative natural insulation materials used today. Compared to commercial insulation materials, these materials have a remarkably low environmental impact. In this context, the use of compressed straw as insulation offers a very low impact in the analysis of its life cycle. However, fire safety has always been a big concern for builders using natural combustible materials. The objective of this study is to document the fire hazard of compressed straw when it is used as an insulating material in wood frame assemblies. Three compressed straw densities (75, 125 and 175 kg/m3) were selected to evaluate their combustion properties and thermal conductivity, in attempt to determine which had the best combination of properties. The selected density straw was then compared to commercially available combustible insulation materials to compare their fire risk. Subsequently, this same density straw was tested in a medium-scale wood frame assembly to evaluate the impact of its fuel load comparatively to a non-combustible insulation material. The results showed that compressed straw with a density of 75 kg/m3 had the best properties of combustion and insulation. The results suggest that compressed straw would most likely have better fire performance compared to combustible insulation materials available on the market. Despite the combustible nature of the compressed straw, the impact of its fuel load in a wooden construction system was less than expected. Because the burning properties of compressed straw are less hazardous than commercially available combustible insulation materials and the impact of its heat load in a wood frame structure, the use of this material as an insulator in a building is, by design, manageable without increasing risks.
Gherardi, Hein Paulo Ricardo. "Contrôle génétique et environnemental de l'angle des microfibrilles dans le bois d'Eucalyptus : effets sur les propriétés du bois et implication pour la sélection". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2011. http://tel.archives-ouvertes.fr/tel-00623042.
Pełny tekst źródłaSaedlou, Nima. "Apports de la xylologie à l'archéologie : étude des objets en bois gallo-romains de la ville de Saintes (Charente-Maritime, France)". Paris 6, 2002. http://www.theses.fr/2002PA066327.
Pełny tekst źródłaAndré, Nicolas. "Méthodologie d'analyse mécanique des structures bois du patrimoine : application à la réhabilitation d'un beffroi". Bordeaux 1, 2003. http://www.theses.fr/2003BOR12683.
Pełny tekst źródłaPreservation of the cultural heritage is an important issue in European countries. Actually, only visual inspection (use of basic tools) and common sense of the surveyor are used to diagnose an old timber structure. In this work, we emphasized the construction of a sharp and fitted mechanical model for each old timber structure diagnosed. Thus, we developed a mechanical analysis methodology based on: ? finite element modelling of the structure, ? determination of the model's influential parameters by design of experiment,? in situ identification of these parameters by NDE tests: - direct,- optimized by the genetics algorithms. We validated this methodology by renovating a wooden bell-tower
Uwizeyimana, Placide. "Suivi de la santé structurale des infrastructures en bois par intégration de capteurs". Thesis, Toulouse 3, 2021. http://www.theses.fr/2021TOU30012.
Pełny tekst źródłaFor a few years, a strong expansion of timber structures has been promoted by the use of glulam. These are mechanically promising and offer the possibility to build long-span and complex architectural structures. However, durability issues related to variable humidity and temperature conditions limit the development of these structures. To promote this renewable and ecological material, it is essential to associate glulam structures with a maintenance and monitoring process in order to intervene as quickly as possible on the structure as soon as there is a risk of pathology occurring. Therefore, this research work has consisted in setting up a continuous monitoring process of glulam structures with embedded sensors between the lamellas of glulam. A wetting/drying (W/D) cycle allowing a study of wood durability properties was proposed and various physico-mechanical parameters of glulam were studied over time, especially its moisture content (MC), dimensional variations and bending strength properties. In this study, the resistive method based on the use of patch-type sensors was used for MC monitoring. Dimensional variations in shrinkage/swelling were measured using strain gauges. Firstly, the continuous measurement and recording system was developed in the IUT of Tarbes. Then, preliminary tests were carried out to validate the glulam instrumentation using embedded sensors and to establish an MC monitoring model that considers variations of relative humidity and temperature. To finish, accelerated durability tests were carried out. These ones consisted in exposing the specimens to the W/D cycles in order to highlight the impact of climatic variation conditions, generally encountered in timber structures, on the mechanical bending strength of glulam. The results show that the measuring system developed allows real-time and continuous monitoring of wood MC, temperature, and shrinkage/swelling deformations. In addition, the W/D cycles lead to a decrease in the bending strength of glulam. Besides, no significant changes in modulus of elasticity have been observed. In the future, durability tests under real climatic conditions will have to be carried out in order to validate the scientific approach and to propose in the end monitoring and maintenance solutions associated with the service of glulam structures managers
Payeur, Mario. "Influence des charges verticales sur les performances latérales des murs de refend en bois à ossature légère". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28074/28074.pdf.
Pełny tekst źródłaIn light-frame buildings, it is diaphragms and shear walls that transfer the lateral forces to the foundation through shear and hold-down restraint. The use of hold-down anchoring devices limits the overturning and therefore improves the lateral resistance of the system. However, these anchors are rarely used in the traditional light-frame construction and the lateral resistance of such systems is largely unknown. One of the factors limiting the overturning of partially restrained walls is the action of the vertical loads. A study was performed at the Laval University aiming at the determination of the influence of the vertical load applied to a wall on its lateral performance. The experimentation program consisted of 43 static and cyclic racking tests on full-size light-frame walls with and without hold-downs. The walls were 2.44-m tall and 2.44-m and 4.88-m long fully sheathed with OSB panels on one side. Three intensities of the vertical dead load were applied to walls without hold-downs: roof load, one storey load and load needed to prevent any overturning (corresponding to a fully restrained wall). Three 4.88-m long walls with hold-downs were tested under one storey load. Control specimens of each configuration were tested without vertical load according to relevant ASTM standards. Results show that application of vertical loads improves maximum capacity of non-anchored walls regardless the load protocol. A comparison of various methods of calculation of the lateral resistance of walls under combined loads was done using experimental verification. The results show that the CSA-O86 method is conservative for low vertical loads, but seems to overestimate the lateral capacity up to 10% for higher loads. The Källsner method is the most conservative. Overall, the design methods give reasonable estimate of the capacity of non-anchored walls used in practice. The calculation of the wall deflections proposed by CSA-O86 was also verified. This formula seems to overestimate the rigidity of non-anchored walls. To stay conservative, a note should be added to the definition of nail deformation, en, indicating that the load per nail should be the one observed for an anchored wall. This formulation is based on the assumption that all sheathing-to-bottom plate nails reach its ultimate capacity. Finally, it was observed that increasing the vertical load decreases the amount of uplift of the chords and therefore increases the work of the nails along the perimeter of the panel, which allows greater rotation of the panels about the frame.
Ho, Nhat-Quang. "Endommagements de composites carbone-époxy induits par la thermo-oxydation de la matrice en présence de contraintes mécaniques". Poitiers, 2006. http://www.theses.fr/2006POIT2294.
Pełny tekst źródłaThis study contributes to the understanding of the damage mechanisms of CFRP laminates subjected to thermo-mechanical stresses in oxidative environment. When these materials are submitted to thermo-mechanical loadings at high temperatures (100°C - 150°C), the presence of oxygen enhances the initiation of surface matrix cracks and accelerates their propagation towards the laminate core, thus leading to a catastrophic damage state. An experimental procedure has been performed in order to dissociate the different damage mechanisms. The analysis of the experimental results, associated with a finite element calculation of the free edge stresses, has led us to propose a damage scenario taking into account coupling between stresses and oxidation for a cross-ply laminated structure subjected to thermal cycling in oxygen environment. In a second part, we study more precisely the changes induced by oxidation in the material properties of neat epoxy matrix. We have shown that oxidation, via an internal anti-plasticization effect, leads to an increase in the indentation elastic modulus, a decrease in the damping capacity and in the glass transition temperature. In addition, it was found that there exists a correlation between the values of the elastic modulus of oxidized material and the concentration of the oxidation products predicted by a kinetic model of oxidation (diffusion - reaction). This phenomenological correlation enables to carry out a coupled "oxido-elastic" calculation in order to determine the stress field generated by the presence of an oxidized layer in a resin structure
Melo, Moura Jorge Daniel de. "Utilisation en structures des résineux à faible densité : conséquences technologiques de scénarios sylvicoles extrêmes". Nancy 1, 1996. http://docnum.univ-lorraine.fr/public/SCD_T_1996_0041_DE_MELO_MOURA.pdf.
Pełny tekst źródłaAudigeos, Delhine. "Relations entre diversité génétique et environnement : quels sont les processus évolutifs mis en jeu? : cas d'une espèce d'arbre tropical, Eperua falcata Aublet". Antilles-Guyane, 2010. http://www.theses.fr/2010AGUY0354.
Pełny tekst źródłaThe tropical forest is characterized by a strong specificdiversity and an elevated level of competition for the space occupation especially at the youthful stages. The occupation strategies of space are related to the methods of seeds dispersion, but probabilities of seed survival until the reproductive age rely on their potential of adaptation to their environment. In this context, i was interested in studying Eperua falcata, one of the dominant tree species in fFrench Guiana, which shows a water-soil-content-related ecological comportment. For this purpose, i decided to explore and compare genetic diversity in candidate genes with known functions (aquaporins, catalase and farnesyltransferase) to the one in randomly picked genomic sequences. First, i described aquaporins geneticdiversity at a regional scale; then i tested interactions between genetic diversity (neutral and adaptative) and the environment (water-soil content) and finally i performed the phylogeographic study of E. Falcata at French Guiana scale
Youssef, Alice. "Prise en compte des apports mécaniques du béton de chanvre pour le calcul de structure bois/béton de chanvre et métal/béton de chanvre". Thesis, Lorient, 2017. http://www.theses.fr/2017LORIS431/document.
Pełny tekst źródłaLime and hemp concrete (LHC) is nowadays the most developed bio-based aggregate building material in Europe. It consists of hemp shiv and mineral binder mixing with water. Generally, bio-based materials like LHC are used for their thermal insulation properties in building. Most blocks of Lime Hemp Concrete which have been studied, show a brittle behavior and a very low mechanical strength. The formulations are generally rich in binder and slightly compacted. Up to now, this material is then not considered as a load bearing material and is mainly used as filler insulation, combined with structure components made of wood, concrete or masonry. A study has tested other formulations, with higher contents of aggregates thanks to a compaction process, in order to improve both the rigidity and the strength of the hardened mixtures. In these formulations, shiv which has higher amount is definitely lighter and more porous than lime, which prevents a significant increase in thermal conductivity. The present work of my PhD is an experimental study of the compressive and shearing behavior of hemp concrete, in order to study the load-bearing capacity and bracing of this bio based material, while maintaining good qualities of thermal insulation in building. Two compacted formulations were tested M1 & M4, as well as samples obtained from trade-blocks Chanvribloc®. Two series of tests were performed. The first one is a uniaxial compression test in each direction for characterizing the mechanical anisotropy of the material. This anisotropy is induced by the compacting process. The second one permits to characterize the shearing behavior of the different mix-designs. In this study, an original shear device was developed, specifically designed for this kind of material, which allows shearing under controlled normal stress. An image processing performed was carried out, using a camera and ARAMIS image processing software during shear tests, to evaluate the fields of deformations and to study the behavior of the specimen during the shear test. The compressive experiments results have shown that this material is anisotropic, even when it is industrially molded by vibrations. The material has a transverse isotropic behavior. The behavior in the longitudinal direction is characterized by very high ductility, while the transverse behavior is very brittle, with a highly variable and unsteady behavior. The experimental results in shear show a high ductility of this material. These results are very promising, an interesting behavior of LHC walls in term of potential bracing. Numerical modeling and applications have been carried out to illustrate the use of hemp concrete blocks for bracing buildings. The formulation M4 exhibits a better behavior under moderate and average seismic actions, compared to the formulation M1, while the Chanvribloc walls in the present state do not allowthe buildings to be braced in moderate or medium seismic zones
Mandallena, Céline. "Elaboration et application d'une méthode d'évaluation et d'amélioration de la qualité environnementale de bâtiments tertiaires en exploitation". Bordeaux 1, 2006. http://www.theses.fr/2006BOR13207.
Pełny tekst źródłaManfoumbi, Boussougou Nicaise. "Contribution à l’adaptation de l’Eurocode 5 aux essences tropicales dans leur environnement". Limoges, 2012. https://aurore.unilim.fr/theses/nxfile/default/0551f36f-4466-48f1-8fa4-7f52805a085f/blobholder:0/2012LIMO4005.pdf.
Pełny tekst źródłaThe present report makes a contribution to adapt Eurocode 5 for timber constructions using tropical hardwoods in tropical climate. This approach requests to well know the mechanical behavior in variable environment. In a first time, an experimental study is presented for decoupling postponed phenomena from a longitudinal four-point creep bending, under controlled climate on small samples by measuring upper and lower deflections. The result of this original experimental protocol allows separating and illustrating different phenomena met on creep evolution of timber beams: swelling-shrinkage effects, hygro-lock effect, orthotropic mechanosorption and viscoelasticity. In second time, longitudinal four-point creep bending tests were realised, in the scale of structure, in tropical atmosphere to Franceville in Gabon, in two tropical hardwoods: Moabi and Ozigo. The experimental device was led on three sites corresponding to three different climatic environments according to specific service classes of Eurocode 5: an atmosphere temporarily air-conditioned, a sheltered outside atmosphere and an outside atmosphere non-sheltered. The obtained results show that tropical wood have a deferred behaviour stressed by the strong variation of humidity for little significant temperature variations. To define new classes of service appropriated for the tropical atmospheres, it is important to characterize the diffusion process. Following this objective, a complete experimental device was led, in the scale of material, in order to determinate the sorption isotherms and diffusion parameters needed to study the mechano-sorptive behavior in real condition. In a last time, others tests of creep and relaxation, in the scale of material, were realized under controlled atmosphere, in the same species. This study, led in low and high relative humidity, shows that the creep is more significant for the wet beams and the recovery is more important when beams are dry. A modeling of the creep-recovery under low and high relative humidity is proposed and allows the determination of the viscoelastic parameters of the studied beams. At the end, a comparative study of creep coefficients, obtained on the laboratory samples and the beams in real environment, shows that the mechanic-sorptive effects are dominating, with an importance of longitudinal swelling-shrinkage effects, not insignificant in the scale of structure
Young, Vigneault Emilie. "Étude dendroarchéologique d'une collection de bois associée à des constructions militaires de la fin du 18e siècle, Île aux Noix, Haut-Richelieu, Québec". Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27190/27190.pdf.
Pełny tekst źródłaYoung-Vigneault, Émilie. "Étude dendroarchéologique d'une collection de bois associée à des constructions militaires de la fin du 18e siècle, Île aux Noix, Haut-Richelieu, Québec". Master's thesis, Université Laval, 2010. http://hdl.handle.net/20.500.11794/22076.
Pełny tekst źródłaLoulou, Louisa. "Durabilité d’un assemblage mixte bois-béton collé sous chargement hydrique". Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1123/document.
Pełny tekst źródłaThe wood-concrete composite is an interesting solution in the field of Civil Engineering to create high performance bending elements for bridge, as well as in the building construction for the design of wood-concrete floor systems. The Navier laboratory has been working for many years on the development of the bonding process as applied to wood-concrete composite structures. Contrary to conventional joining connectors (metal connectors), this assembling technique does ensure an almost perfect connection between wood and concrete. Previous work has already shown good performances of glued wood-concrete composite structures in terms of mechanical fatigue. However, the bonding connection requires additional research on the long-term behaviour of glued wood-concrete composites, especially when this structure is subjected to variable hygrometric conditions. The work undertaken during this thesis aims at determining the factors which induce damages on these glued wood-concrete assemblies under hygrometric loading; the research is divided into 3 parts:-Two experimental parts:(1)"Push-Out" shear tests conducted in collaboration with the Departmental Laboratory of Autun, were used to assess the effect of the elastic properties of the resin on the shear strength of the assembly. This experimental study aims at validating the adhesive of choice for this kind of connection, taking into account ageing under variable hygrometric conditions. Analysis is based on maximum shear capacity and on the failure mode of the assembly. (2)In addition to shear tests, the effect of hygrometric loading on the durability of glued wood concrete assemblies was examined. The analysis of the hydric behaviour of the structure was carried out by the digital image correlation (DIC) technique on small-sized glued wood-concrete assemblies. The measurements of the local deformations allowed us to locate areas of damage, particularly due to the hydric deformations of the wood prevented by the glued connection The effects of the elastic properties of the resin, the microstructure of the wood (including its structure and the direction of the annual rings) as well as the mechanical behaviour of the concrete material were examined.- A numerical part:(3) A numerical finite element model was validated by comparing the numerical results to the deformation maps experimentally obtained. Numerical analysis was used to quantify the stresses induced to the structure, in relation to hydric deformations prevented by glued connection. Moreover investigations at the full scale were conducted to evaluate the long-term behaviour under variable hygrometric conditions. These investigations were conducted in order to offer solutions aiming at optimizing this type of connection, and to define conditions for use of these glued assemblies
Terrei, 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.
Pełny tekst źródłaThe 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
Boyancé, Patrick. "Modélisation de la rupture différée d'un matériau orthotrope viscoélastique en environnement naturel : application à un composite à base de bois : le LVL". Bordeaux 1, 1999. http://www.theses.fr/1999BOR10656.
Pełny tekst źródłaFochesato, Andrea. "Aux origines de la ville européenne : technologie, typologie et fonction de l'architecture en bois dans l'habitat urbain des oppida celtiques (IIe-IIer s. av. J.-C.) : le cas de Bibracte, mont Beuvray (France)". Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCH002.
Pełny tekst źródłaThe aim of this work is to clarify the knowledge on the architectural aspect of the oppida in Temperate Europe during the two last Centuries BC. The study is based on the oppidum of Bibracte (mount Beuvray, Burgundy), one of the reference sites for the Period in Europe. The research focused mainly on the study of timber building techniques derived from the continental protohistoric tradition and commonly used in these settlements.The entire woodworking process, from the forest supply to the different stages of building construction, has been analysed. The technical aspects related to the foundation and elevation of the building’s frames, the choice and shaping of their wooden elements, the patterns of the walls and the roofing techniques has been apprehended through the analysis of the archaeological remains – often fragmentary and difficult to read – as well as through the study of the rare timbers preserved in particular taphonomic conditions on the site.Thanks to the cross-checking of the documentation available from the 75 years of research carried out on mount Beuvray in the 19th century (1864-1907) and from 1984 to the present day, 151 structures with sufficiently complete plans has been identified. Of these, 74 wooden-frame buildings are characteristic of an indigenous architectural tradition, while 77 masonry structures show some influences linked to the new techniques and modules coming from Italy and gradually introduced in the settlement during the last two decades of the 1st century BC.The wooden architecture of Bibracte reflects the image of an expertise particularly well adapted to the very constraining morphological characteristics of the terrain of mount Beuvray. The corpus of studied buildings has been divided in 13 architectural categories, 6 of which concern wooden-frame buildings. In the sectors with steeper slopes, houses are usually composed of one or more semi-buried rooms and organised in terraces. The volume of these buildings develops rather vertically, with limited footprint (spans rarely exceed 5 m, the structures do not require any internal load-bearing system), but with massive wooden frames. The latter are built using closely squared timber posts, installed in dry stone trenches or connected by foundation beams giving to the structure a remarkable load-bearing capacity to support the weight of an upper floor. In the less steeply sloping areas, the buildings develop more horizontally, with multi-room layouts (often with wooden cellars) or with a monumental aspect in public buildings.Although they are organized in different ways, many structures display a certain uniformity in their dimensions, suggesting the use of well-defined building modules and a precise measurement system within a standardized building activity in the site. As in the case of the habitat, the existence of distinct parameters could also be observed in the construction of the wood-framed ramparts (murus gallicus) of the oppidum, as well as for the wooden timbers preserved on the site
François, Jessica. "Modélisation et évaluation environnementale des filières de cogénération par combustion et gazéification du bois". Electronic Thesis or Diss., Université de Lorraine, 2014. http://www.theses.fr/2014LORR0071.
Pełny tekst źródłaBiomass is one of the most promising renewable energy source in Europe. Its use as a substitute to fossil energy is expected to mitigate climate change. However, potential drawbacks are also feared with large scale development. In order to assess the environmental impacts of the biomass-to-energy chain, we firstly developed a model of the bioenergy system, from the forest to the energy production. We focused on two biomass power plants for combined heat and power (CHP) production: one is based on the conventional direct combustion process while the other is based on the more advanced gasification process. Gasification offers higher electrical efficiency, but its development is still facing technical difficulties. In case of the gasification process, we defined the best operating conditions regarding energetic and exergetic efficiencies, as well as the syngas quality requirements. Secondly, we calculated the carbon and mineral flows taken from the forest through energy wood harvesting, along with the forested area required to feed the CHP plant. The other resources and emissions related to the plant operation were also predicted. We observed that more extensive forestry practices led to an increase in the mineral exports. Finally, we evaluated the environmental performance of the two biomass CHP plants using life cycle assessment (LCA). Within French energy context, we found that both CHP technologies had very similar impacts with a slight advantage toward the combustion process. It appears of particular benefit to replace current fossil energy systems with biomass CHP plants to reduce climate change
Piot, Amandine. "Hygrothermique du bâtiment : expérimentation sur une maison à ossature bois en conditions climatiques naturelles et modélisation numérique". Phd thesis, INSA de Lyon, 2009. http://tel.archives-ouvertes.fr/tel-00440510.
Pełny tekst źródłaBohineust, Xavier. "Développement de méthodes de mesures d'intensité acoustique : application à l'étude du rayonnement et des transmissions dans les structures à ossature bois". Compiègne, 1987. http://www.theses.fr/1987COMPI258.
Pełny tekst źródłaThe mechanisms of direct and flanking acoustical transmissions in building or industrial structures are highly dependent of the nature of the structure, the connections between pannels, the acoustical and vibrating coupling between structure cavity. When a detailed diagnosis of radiation and transmission characteristic is required while the building or machine on site. Acoustic intensity measurement could be very useful. But a limitation of the standard two-microphone acoustic intensity method is its inhability to distinguish the radiated intensity of a source in the presence of extra sources creating interactive intensity field. The selective technique of acoustic intensity proposed by Bucheger has been developped and studied in the present thesis. The analytical expressions of active, reactive, inter-actived and inter-reactive intensities have been developped. Signal processing has been processed and implanted on micro-computer. Experimental studies of the bias and statistical errors have been made. Referential phase correction methods of the two microphone intensity probe has been proposed and developped. Application and validation of the referential selective inetensity method has been implemented on a full size model wood frame building
Bélanger, Jean. "Caractérisation des transferts hygrothermiques dans une enveloppe de bâtiment en bois par la résolution d'un problème inverse par l'optimisation des propriétés physiques des matériaux". Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69706.
Pełny tekst źródłaTlijani, Mohamed. "Contribution à la caractérisation thermophysique de matériaux bio-isolants : valorisation des déchets de bois de palmier". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1157/document.
Pełny tekst źródłaThe growing interest in new concrete and their use in many fields of civil engineering was that we wanted to bring a new approach to the design of a new product consisting of a reinforced concrete with basel end frond palm fibers. This led us to conduct the experimental study of thermal properties of natural fibers of date palm (Phoenix dactylifera L.). The analysis of experimental results showed that the essential factors affecting the thermal conductivity are the variety of date palm and the fiber orientation and that the basel end of the frond palm is the most interesting part as thermal insulation. However, the main problem encountered when using plant fibers as reinforcement is cohesion, bonding with the matrix and dimensional instability so the composite loses its mechanical properties. In this context, an alkaline pretreatment of palm fibers was envisaged to clean and modify the fiber surface to address the problems of dimensional stability of the fibers and degradation before their use as reinforcement in the cement matrix. We also studied the influence of chemical treatment with sodium hydroxide on the mechanical properties of processed samples, they were subjected to the tensile test to estimate the fracture strength for each treatment concentration, the Young's modulus and elongation at break corresponding. Subsequently, we conducted experimental and theoretical research on the thermal conductivity of different formulations of basel end palm wood concrete composite. The study of the theoretical apparent thermal conductivity was based on an approach that relies on a process whereas the material consists of a solid matrix combined with a fluid phase (air). Finally, we performed a numerical simulation of heat transfer phenomena to assess the thermal conductivity of basel end frond palm concrete composite and validate subsequently the theoretical prediction model selected. The results showed that the numerical approach based on the isotropic orientation of the particles in the composite coincides and approaches the physical reality
Martin, Ulysse. "Spécificités physiques et enjeux de la performance énergétique du CLT en milieu nordique". Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/30955.
Pełny tekst źródłaWood is one of the first material mankind used to work with and is still full of potential for building sector. Many engineering materials have been developed from wood, such as the cross-laminated timber (CLT). Wooden engineering materials are as performant as steel and concrete but are also cost effective and have a lower environmental footprint. Resources extraction for the manufacture of building materials and the building phase itself require a lot of energy, and generate or release important amount of greenhouse gaz. Wood is a sustainable resource that has the benefit of being able to capture carbon during its growing phase and to preserve it. In service, buildings will have heating and cooling loads, depending of their energy efficiency, high energy efficiency is required to lower the overall energy footprint of buildings. CLT has the potential to be a greener substitute to reinforced concrete in the mid-rise building. CLT helps to reach energy efficiency because wood panels act as a barrier for air, vapor and heat. In CLT building system, junctions between panels and with other elements (ducts, wiring, etc) are the main leakage paths through the envelope. Infiltrations and exfiltrations are responsible for important heat losses. Exfiltrations can also lead to excessive moisture accumulation in the walls, resulting in mold and rot growth. Structural integrity and air quality can be jeopardized on the average/long term. The aim of this project was to assess the impact of gaps between CLT panels, in case of air leakages, on the energy efficiency and durability of the wall. A real case of infiltration in a corner of a CLT building was used to size an air leakage area in the insulation (0.72 mm through the insulation considering a 1 m high wall), intended an assembly tolerance or gap of 2 mm. The gap was then extrapolated to a flat wall, to exclude the thermal bridge effect of the corner. An energy efficiency assessment was done using simulations for both cases of infiltration and exfiltration, with variable assembly gap. Simulation also permits to assess the impact on durability, on mold growth risks, of the exfiltration for variable exfiltrated air relative humidity. Results show that infiltration has a greater impact (1.62 times) than exfiltration, which is itself 1.37 times more energy-consuming than a perfect wall. The impact of the assembly gap variations in the CLT is restricted by a maximum flow rate dicted by the air leakage path in the insulation. Simulation of moisture transfer shows that mold growth is to fear on the gap surface through the wall, when the exfiltrated air relative humidity exceeds 40 %. The first mold development should primarily affects the insulation, but extends to the CLT as the relative humidity of the exfiltrated air increases. Condensation occurs in the insulation near the outlet of the exfiltration, leading to an accumulation of ice behind the external cladding. Results of simulations show how important it is to keep the air barrier continuous, and to avoid that assembly gaps in the CLT act as shortcut for eventual air leaks. The use of flexible adhesive joints, which can match the irregular cut of the CLT and dampen the dimensional variations would reduce the risks of air leakage.
Li, Hang. "Utilisation de matériaux bois intelligents pour la gestion durable des infrastructures". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30288/document.
Pełny tekst źródłaFor fifteen years, we restart to construct with wood, and particularly with glulam to respond to the new challenges imposed by the issues of sustainable development. However, degradation issues related to moisture content (MC) or wetting/drying cycles limit the development of timber structures. As a result, the MC monitoring in timber structures becomes a critical issue. Today, several solutions exist but they do not allow a local monitoring in the lamellas of glulam. Such a solution would improve the prediction of the service life of timber structures. In the light of this observation, we proposed to transform glulam into "smart material" by embedding a MC monitoring system in the lamellas, and this, considering the major constraints of fabrication of this material (small glue line thickness, important bonding pressure, etc.). To achieve this, we have conducted a bibliographic research, in order to select the monitoring methods which can satisfy these constraints. According to this research, two technologies turn out to be interesting: the electrical measurements and the ultrasonic measurements. Several measurement configurations were proposed and tested in this PhD work. Thereafter, we conducted preliminary tests to make sure of the good functionality of these measurement configurations, and also to verify the behavior of sensors throughout the glulam fabrication process. Afterwards, we moistened the specimens with two different moistening protocols in order to verify the feasibility of MC monitoring with embedded sensors. Results showed that all the measurement configurations are operational for the MC monitoring in glulam specimens. Moreover, for electrical measurements, our results show that we can adopt almost the same calibration models for the MC monitoring by resistive measurements, no matter the type of sensors used. Furthermore, it is possible to obtain complementary information by the realization of the resistive and capacitive measurements at the same time, using surface electrodes. Regarding the ultrasonic measurements, we have obtained the sensibility curves in frequency of several families of piezoelectric film sensors. On the other hand, the influence of bonding pressure and of sensor distance on the electrical/ultrasonic measurements was also investigated in this study. Future studies will consist in using these measurement configurations to perform in situ monitoring in timber structures, and also to establish a link between the durability of glulam structures and the wetting/drying cycles in order to predict the service life of timber structures
Lemaître, Romain. "Développement d’un outil de calcul non linéaire de dimensionnement d’assemblages bois tridimensionnels soumis à des torseurs plans". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0046.
Pełny tekst źródłaThe aim of this PhD is to propose a numerical modelling engineering tool for the design of dowelled timber joints with in-plane loading (N, M, V). It is part of a context where the needs of the engineers for the design of these kind of joints are increasing, in particular on the connection stiffness estimation and the load distribution. A three-dimensional model of an elastoplastic beam on non-linear supports was chosen as the basis for development in order to model the local mechanical behaviour of the dowel-wood interaction. These nonlinear supports are used to describe the embedment behaviour of the dowel in the thickness of the timber members. Embedding tests on several materials and dowel diameters were carried out to characterize this behaviour. Methodology to analyse embedment test curves was proposed to be in line with the model used. Within the framework of a European collaborative work, this methodology was used on experimental results from four research laboratories in order to provide a database. The database analysis has made it possible to find some empirical correlations to estimate physical parameters related to the embedment. The proposed modelling is developed using the Cast3M finite element calculation code. It integrates all the material behaviours of the joint components. It gives an accurate estimate of the load distribution of the joint generated by in-plane loading, as well as the axial and rotational stiffnesses. The numerical model has revealed the influence of the dowel slenderness on the connection stiffness estimation
Christin, Jérôme. "Système de fondation sur pieux bois : une technique millénaire pour demain". Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1105/document.
Pełny tekst źródłaMany buildings and bridges built on timber pile foundations still stand in France. The bridges on rivers “Loire” and “Seine”, the castle of Chambord, the “Grand Palais” in Paris are a few examples of French monuments founded on timber piles. However, despite a large number of buildings and bridges constructed in France, the feedback on the residual bearing capacity and the degradation of timber piles is scarce. The main objectives of this work, which is part of the “Pieux Bois” national research project, are, on the one hand, to define a methodology in order to analyze timber pile foundations degradation, and on the other hand, to propose a design method of timber piles based on the results obtained from pressuremeter tests. The state of the art made in the national project identified about one hundred French bridges built on timber piles between the Middle Ages and the industrial era. They are mainly located in basins of rivers. Pathologies were observed on bridges and reinforcement solutions were implemented in order to avoid any future problems. The methodology for the inspection of timber pile foundations given in the Dutch guide was applied to investigate the degradation of timber piles under an existing railway bridge near Bordeaux. Series of laboratory tests were carried out on soil (silt) and wood with a direct shear box. The mechanical properties of the interface were studied. Shear tests between mortar, steel and silt were also carried out. The influence of material roughness and silt moisture content on the shear strength properties of the interface was examined. In addition, timber piles were driven and loaded on two experimental sites. The timber piles were instrumented with removable extensometers. The results of these load tests were included in a database which contained timber piles loading test results published in literature. The approach adopted to establish the design method of deep foundation based on the results obtained from pressuremeter tests described in the new national standard for application of Eurocode 7 was modified. A new model of calculation of timber piles shaft and base resistance driven in clay silt and sand gravels was determined with statistical studies from this database