Dans un contexte d’optimisation des lignes de production, la maîtrise de la qualité des pièces et des capacités machines est primordiale. Plusieurs études se sont intéressées à la formation des bavures en usinage mais les mécanismes sont encore peu connus, bien qu’un lien fort avec les efforts de coupe soit établi par divers auteurs. Ainsi, la maîtrise des efforts de coupe a un intérêt double : optimiser les lignes de production et servir de donnée d’entrée pour la prédiction de la taille des bavures. Cette étude propose donc de renforcer les connaissances concernant les mécanismes de formation des bavures générées par un outil en sortie matière, et de prédire les efforts de coupe en fraisage grande vitesse, dans l’alliage d’aluminium AlSi7Mg0,3+0,5Cu. Divers mécanismes de formation de bavures sont étudiés en coupe élémentaire. Une nouvelle méthode de mesure in situ permet d’identifier l’influence des conditions opératoires sur l’évolution statistique de critères géométriques caractérisant les bavures générées de façon hétérogène dans le cas de l’alliage étudié, dont le comportement est fortement dépendant de son état de contrainte local ainsi que de sa microstructure. Une analyse des champs de déplacement et déformation par corrélation d’images couplée ainsi qu’un modèle de simulation par éléments finis permettent d’identifier plus finement les mécanismes de formation des bavures. Le surfaçage est étudié pour modéliser les efforts de coupe puis comparer les efforts produits lors de la sortie des dents avec les caractéristiques des bavures obtenues. Enfin, une stratégie de minimisation de la hauteur des bavures en surfaçage à la fraise grande avance est étudiée. / In a context of production lines optimization, parts quality and machine capabilities control is essential. Several studies have been carried out on machining burr formation but the mechanisms are not fully understood, although a strong link between burrs formation and cutting forces is established by several authors. Hence, controlling the cutting forces has two advantages: optimize the production lines and be used as input data for a burr height model. This study proposes to consolidate the knowledge on burr formation mechanisms during the exit of a tooth, and to predict cutting forces during high speed milling of the AlSi7Mg0.7+0.5Cu alloy. Various burr formation mechanisms are studied in orthogonal cutting. A new in situ measurement method allows to identify the statistical influence of some operational conditions on the evolution of some newly introduced geometrical parameters defining the burrs heterogeneously formed in the case of the studied alloy, whose behavior strongly depends on its local stress state as well as its microstructure. A displacement and strain field analysis using Digital Image Correlation, as well as a finite element model provide a better understanding of the burr formation mechanisms. Face milling is studied to model cutting forces and compare the forces produced during the exit of a tooth to the obtained burr morphologies. Finally, a burr height reduction strategy is proposed using a high feed mill.

The objective of this dissertation is to understand how social-political conservative and liberal movements worked in the construction and consolidation of Coup d’État Civilian- Military of 1964, from his performance on the hegemonic, political and political-institutional fields in Rio Grande do Sul, Brasil. With this this objective, the first chapter treats the themes referencing to anticomunism, the Cold War and the ideological clashes that arose from this context that produced a growing polarization in the Brazilian political forces. The ideological glue that unifies the conservative forces, despite their multiplicity, in coping the project of the anti-reformists, has on the Catholic Church and the Press its main vehicle of transmission. In the second chapter, the subject is the political vanguard of the conservative segment of civil society organizations, in particular the self-labeled as producing classes, both in its urban extent, through FIERGS and FEDERASUL, and the rural, with FARSUL. In the third chapter we study the performance of the institutional and political liberals and conservatives forces to support and legitimize the Coup d’État Civilian-Military of 1964, through political parties as PSD, UDN, PDC, PRP and PL, their partisan front, the ADP, and factor decisive in triggering the coup, the government Ildo Meneguetti, fundamental for the success civilian-military coup in Rio Grande do Sul. On this dissertation, we try to demonstrate in practice how socialpolitical liberal and conservative movements work in building and sustaining the Coup ‘État, from its political action in the ideological field, on public opinion and at the political institutions. If we think of it as a preemptive strike, because it is an action triggered against the rise of social movements' struggles and nationalist politicians and reformers and their programs, it is important to highlight that, dialectically, we think about a social-political movement that brings together wide liberals and conservatives sectors on behalf of a project based on the formulations of the National Security and Development Doctrine. The takeover is only possible because of this work arduously growth, which allowed much of the Brazilian society to accept, back in 1964, the project of authoritarian development. / O objetivo dessa dissertação é compreender como os movimentos sociais e políticos conservadores e liberais atuaram na construção e consolidação do Golpe Civil-Militar de 1964, a partir de sua atuação no campo hegemônico, político e, político-institucional no Rio Grande do Sul. Com este objetivo, o capítulo um trata dos temas referentes ao anticomunismo, à Guerra Fria e os embates ideológicos advindos desse contexto que produziu uma polarização crescente nas forças políticas brasileiras. O cimento ideológico que unifica as forças conservadoras, apesar de sua multiplicidade, no enfrentamento aos projetos reformistas é o anticomunismo, tendo na Igreja Católica e na Imprensa seus principais veículos de transmissão. No segundo capítulo, o objeto é a vanguarda política do segmento conservador da sociedade civil organizada, em especial, as auto identificadas como classes produtoras, tanto em sua dimensão urbana, através da FIERGS e da FEDERASUL, quanto a rural, com a FARSUL. No terceiro capítulo estudamos a atuação política institucional das forças liberais e conservadores, para apoiar e legitimar o Golpe Civil-Militar de 1964, através dos partidos políticos, PSD, UDN, PDC, PRP e PL, sua frente partidária, a ADP, e o fator decisivo na deflagração do Golpe de Estado, o governo Ildo Meneguetti, fundamental para o sucesso do Golpe civil-militar no Rio Grande do Sul. Nesta dissertação tentamos demonstrar, como os movimentos sociais e políticos liberais e conservadores atuam na construção e sustentação do Golpe, a partir da sua atuação política no campo das ideias, da opinião pública e no plano político institucional. Se podemos pensá-lo como um golpe preventivo, pois, tratase de uma ação deflagrada contra a ascensão das lutas dos movimentos sociais e políticos nacionalistas e reformistas e seu programa, é importante destacar que, dialeticamente, trata-se de um movimento sócio-político que aglutina amplos setores liberais e conservadores em nome de um projeto baseado nas formulações da Doutrina de Segurança Nacional e Desenvolvimento. Resultado de um intenso trabalho conspiratório e de conquista da hegemonia política para efetivação do programa de crescimento econômico e modernização autoritária. A tomada de poder somente é possível porque este trabalho, arduamente desenvolvido, permitiu que boa parte da sociedade brasileira aceitasse, naqueles idos de 1964, o projeto de desenvolvimento autoritário.

Dans cette thèse, les réseaux coopératifs sont étudiés sous cette hypothèse que la source est incertain par rapport le canal en opération. Dans le premier chapitre, des stratégies coopératives sont développées pour les canaux à relais simultanés (SRC) lesquelles se composent d'un ensemble de deux canaux à relais parmi lesquels le canal en opération est choisi. Cela est équivalent au canal de diffusion à relais (BRC). Les bornes sur la région de capacité de BRC général sont dérivées. Les résultats de capacité sont obtenus pour les cas particuliers du canal à relais simultané semi-dégradé et dégradé Gaussien. Dans le deuxième chapitre, le canal à relais composite est considéré où le canal est tiré aléatoirement d'un ensemble de la distribution conditionnelle. Le débit est fixé en dépit du canal actuel et la probabilité d'erreur (EP) asymptotique est caractérisée. Une nouvelle stratégie de codage sélectif (SCS) est introduit permettant aux relais de choisir -selon leur mesurage du canal - la meilleur schéma de codage entre Décoder-et-Transmettre (DF) et Comprimer-et-Transmettre (CF). Les théorèmes de codage de réseau bruit généralisées sont démontrés pour le cas de réseau unicast général où les relais utilisent soit DF soit CF. Dans le troisième chapitre, le spectre asymptotique de EP est introduit en tant que nouvelle mesure de performance pour réseaux composites. Il est démontré que chaque code avec le débit hors de la borne cut-set, abouti à EP égal à un et le spectre asymptotique de EP coïncide avec la probabilité d'outage pour les réseaux satisfaisant la converse forte.

The objective of this dissertation is to understand how social-political conservative and liberal movements worked in the construction and consolidation of Coup d’État Civilian- Military of 1964, from his performance on the hegemonic, political and political-institutional fields in Rio Grande do Sul, Brasil. With this this objective, the first chapter treats the themes referencing to anticomunism, the Cold War and the ideological clashes that arose from this context that produced a growing polarization in the Brazilian political forces. The ideological glue that unifies the conservative forces, despite their multiplicity, in coping the project of the anti-reformists, has on the Catholic Church and the Press its main vehicle of transmission. In the second chapter, the subject is the political vanguard of the conservative segment of civil society organizations, in particular the self-labeled as producing classes, both in its urban extent, through FIERGS and FEDERASUL, and the rural, with FARSUL. In the third chapter we study the performance of the institutional and political liberals and conservatives forces to support and legitimize the Coup d’État Civilian-Military of 1964, through political parties as PSD, UDN, PDC, PRP and PL, their partisan front, the ADP, and factor decisive in triggering the coup, the government Ildo Meneguetti, fundamental for the success civilian-military coup in Rio Grande do Sul. On this dissertation, we try to demonstrate in practice how socialpolitical liberal and conservative movements work in building and sustaining the Coup ‘État, from its political action in the ideological field, on public opinion and at the political institutions. If we think of it as a preemptive strike, because it is an action triggered against the rise of social movements' struggles and nationalist politicians and reformers and their programs, it is important to highlight that, dialectically, we think about a social-political movement that brings together wide liberals and conservatives sectors on behalf of a project based on the formulations of the National Security and Development Doctrine. The takeover is only possible because of this work arduously growth, which allowed much of the Brazilian society to accept, back in 1964, the project of authoritarian development. / O objetivo dessa dissertação é compreender como os movimentos sociais e políticos conservadores e liberais atuaram na construção e consolidação do Golpe Civil-Militar de 1964, a partir de sua atuação no campo hegemônico, político e, político-institucional no Rio Grande do Sul. Com este objetivo, o capítulo um trata dos temas referentes ao anticomunismo, à Guerra Fria e os embates ideológicos advindos desse contexto que produziu uma polarização crescente nas forças políticas brasileiras. O cimento ideológico que unifica as forças conservadoras, apesar de sua multiplicidade, no enfrentamento aos projetos reformistas é o anticomunismo, tendo na Igreja Católica e na Imprensa seus principais veículos de transmissão. No segundo capítulo, o objeto é a vanguarda política do segmento conservador da sociedade civil organizada, em especial, as auto identificadas como classes produtoras, tanto em sua dimensão urbana, através da FIERGS e da FEDERASUL, quanto a rural, com a FARSUL. No terceiro capítulo estudamos a atuação política institucional das forças liberais e conservadores, para apoiar e legitimar o Golpe Civil-Militar de 1964, através dos partidos políticos, PSD, UDN, PDC, PRP e PL, sua frente partidária, a ADP, e o fator decisivo na deflagração do Golpe de Estado, o governo Ildo Meneguetti, fundamental para o sucesso do Golpe civil-militar no Rio Grande do Sul. Nesta dissertação tentamos demonstrar, como os movimentos sociais e políticos liberais e conservadores atuam na construção e sustentação do Golpe, a partir da sua atuação política no campo das ideias, da opinião pública e no plano político institucional. Se podemos pensá-lo como um golpe preventivo, pois, tratase de uma ação deflagrada contra a ascensão das lutas dos movimentos sociais e políticos nacionalistas e reformistas e seu programa, é importante destacar que, dialeticamente, trata-se de um movimento sócio-político que aglutina amplos setores liberais e conservadores em nome de um projeto baseado nas formulações da Doutrina de Segurança Nacional e Desenvolvimento. Resultado de um intenso trabalho conspiratório e de conquista da hegemonia política para efetivação do programa de crescimento econômico e modernização autoritária. A tomada de poder somente é possível porque este trabalho, arduamente desenvolvido, permitiu que boa parte da sociedade brasileira aceitasse, naqueles idos de 1964, o projeto de desenvolvimento autoritário.

The objective of this dissertation is to understand how social-political conservative and liberal movements worked in the construction and consolidation of Coup d’État Civilian- Military of 1964, from his performance on the hegemonic, political and political-institutional fields in Rio Grande do Sul, Brasil. With this this objective, the first chapter treats the themes referencing to anticomunism, the Cold War and the ideological clashes that arose from this context that produced a growing polarization in the Brazilian political forces. The ideological glue that unifies the conservative forces, despite their multiplicity, in coping the project of the anti-reformists, has on the Catholic Church and the Press its main vehicle of transmission. In the second chapter, the subject is the political vanguard of the conservative segment of civil society organizations, in particular the self-labeled as producing classes, both in its urban extent, through FIERGS and FEDERASUL, and the rural, with FARSUL. In the third chapter we study the performance of the institutional and political liberals and conservatives forces to support and legitimize the Coup d’État Civilian-Military of 1964, through political parties as PSD, UDN, PDC, PRP and PL, their partisan front, the ADP, and factor decisive in triggering the coup, the government Ildo Meneguetti, fundamental for the success civilian-military coup in Rio Grande do Sul. On this dissertation, we try to demonstrate in practice how socialpolitical liberal and conservative movements work in building and sustaining the Coup ‘État, from its political action in the ideological field, on public opinion and at the political institutions. If we think of it as a preemptive strike, because it is an action triggered against the rise of social movements' struggles and nationalist politicians and reformers and their programs, it is important to highlight that, dialectically, we think about a social-political movement that brings together wide liberals and conservatives sectors on behalf of a project based on the formulations of the National Security and Development Doctrine. The takeover is only possible because of this work arduously growth, which allowed much of the Brazilian society to accept, back in 1964, the project of authoritarian development. / O objetivo dessa dissertação é compreender como os movimentos sociais e políticos conservadores e liberais atuaram na construção e consolidação do Golpe Civil-Militar de 1964, a partir de sua atuação no campo hegemônico, político e, político-institucional no Rio Grande do Sul. Com este objetivo, o capítulo um trata dos temas referentes ao anticomunismo, à Guerra Fria e os embates ideológicos advindos desse contexto que produziu uma polarização crescente nas forças políticas brasileiras. O cimento ideológico que unifica as forças conservadoras, apesar de sua multiplicidade, no enfrentamento aos projetos reformistas é o anticomunismo, tendo na Igreja Católica e na Imprensa seus principais veículos de transmissão. No segundo capítulo, o objeto é a vanguarda política do segmento conservador da sociedade civil organizada, em especial, as auto identificadas como classes produtoras, tanto em sua dimensão urbana, através da FIERGS e da FEDERASUL, quanto a rural, com a FARSUL. No terceiro capítulo estudamos a atuação política institucional das forças liberais e conservadores, para apoiar e legitimar o Golpe Civil-Militar de 1964, através dos partidos políticos, PSD, UDN, PDC, PRP e PL, sua frente partidária, a ADP, e o fator decisivo na deflagração do Golpe de Estado, o governo Ildo Meneguetti, fundamental para o sucesso do Golpe civil-militar no Rio Grande do Sul. Nesta dissertação tentamos demonstrar, como os movimentos sociais e políticos liberais e conservadores atuam na construção e sustentação do Golpe, a partir da sua atuação política no campo das ideias, da opinião pública e no plano político institucional. Se podemos pensá-lo como um golpe preventivo, pois, tratase de uma ação deflagrada contra a ascensão das lutas dos movimentos sociais e políticos nacionalistas e reformistas e seu programa, é importante destacar que, dialeticamente, trata-se de um movimento sócio-político que aglutina amplos setores liberais e conservadores em nome de um projeto baseado nas formulações da Doutrina de Segurança Nacional e Desenvolvimento. Resultado de um intenso trabalho conspiratório e de conquista da hegemonia política para efetivação do programa de crescimento econômico e modernização autoritária. A tomada de poder somente é possível porque este trabalho, arduamente desenvolvido, permitiu que boa parte da sociedade brasileira aceitasse, naqueles idos de 1964, o projeto de desenvolvimento autoritário.

La qualité des surfaces des veines fluides fermées des pièces tournantes de turbomachine participe au rendement de la turbomachine. Il est donc essentiel de maîtriser la finition des veines en usinage 5 axes avec une fraise boule. L'alliage de titane Ti6Al4V est l'un des matériaux utilisés et souffre d'une faible usinabilité. Le choix des paramètres de coupe conditionne la qualité de surface et la durée de vie de la fraise. Pour maîtriser le fraisage 5 axes, des méthodes de caractérisation de la coupe sont développées pour des trajectoires linéaire et circulaire. Les diamètres effectifs et l'épaisseur coupée sont à l'origine de plusieurs phénomènes associés à la coupe tels que la vitesse de coupe, la vitesse d'évolution de l'usure d'outil, des modes d'usinage et des efforts de coupe. Des essais font le lien entre les mesures d'efforts de coupe et d'état de surface avec les méthodes de caractérisation de la coupe. Une fois l'usinage 5 axes en fraise boule caractérisé, deux stratégies de finition multiaxes de veines fermées sont développées en gardant constantes la vitesse d'avance du point générateur et l'orientation relative de l'axe de l'outil avec la normale de la surface locale. La stratégie de tréflage se caractérise par une trajectoire continue en courbure. La stratégie de contournage hélicoïdal met en évidence des discontinuités en tangence de la trajectoire. Une méthode de lissage local de trajectoire est alors développée pour assurer un comportement cinématique et dynamique raisonnable de la machine. / The surface quality of closed fluid veins rotating parts of turbo machines participates in the machine output. It is therefore essential to control the finishing of veins in 5-axis machining with a ball end mill. The titanium alloy Ti6Al4V is one of the materials used and suffers from a poor machinability. The choice of cutting parameters affects the surface quality and the life of the cutter. In order to control the 5-axis milling, characterization methods of cutting are developed for linear and circular paths. Effective diameters and the uncut chip thickness is responsible for several phenomena associated with the cut such as the cutting speed, the speed of evolution of the tool wear, the milling modes and cutting forces. Tests are the link between measures of cutting forces and surface quality and characterization methods of cutting. Once the 5-axis machining with ball end mill characterized, two strategies of finishing closed veins in multiaxis are developed keeping constant the feed speed of the contact and the relative orientation of the tool axis with the normal the local surface. The plunge milling strategy is characterized by a curvature continuous trajectory. The helical milling strategy reveals tangent discontinuities of the trajectory. A method of local smoothing trajectory is then developed to provide a reasonable kinematics and dynamics behavior of machine.

Le perçage profond (Lu >= 5 x Øoutil) à l'aide de la technologie BTA (Boring Trepanning Association) intervient lorsqu'on souhaite fabriquer des pièces avec un bon rendement productif associé à une bonne qualité d'usinage. Les industries mécaniques évoluent dans un contexte de concurrence perpétuelle, avec des exigences technico-économiques toujours plus importantes. Cette étude résulte donc de la volonté de plusieurs acteurs industriels (AREVA et CIRTES) et universitaire (LEMTA, Université de Lorraine), de faire progresser la compréhension des mécanismes d'usinage qui régissent ce procédé. Une analyse bibliographique approfondie a révélé que cette technologie propose un champ d'investigation très vaste et relativement peu exploré car difficile à appréhender et à étudier. Le but de ce travail est d'analyser et de modéliser les phénomènes ayant lieu au cours d'une opération de perçage profond. Une analyse de la morphologie des copeaux a permis d'introduire un nouveau paramètre permettant d'évaluer les contraintes mécaniques subies par le matériau usiné. L'approche proposée permet quant elle de définir le torseur des contraintes mécaniques en intégrant la géométrie effective de coupe, et ce pour toutes les surfaces de coupe actives d'une tête de forage BTA. Les principes des modélisations utilisées permettent une application relativement aisée à de nombreux matériaux et à partir de l'identification d'un minimum de paramètres. Des moyens expérimentaux originaux ont permis d'identifier des paramètres ainsi que d'ajuster et d'étudier la validité des modélisations. Les limitations de la loi de comportement utilisée ont été mises en évidences, et des perspectives d'études complémentaires ont donc été proposées.Néanmoins, l'ensemble des résultats issus de cette étude ouvrent, modestement, des perspectives intéressantes, notamment dans le domaine d'aide aux choix des paramètres de coupe optimaux, et pour l'aide à la compréhension des phénomènes physiques de la coupe / Deep drilling (Drilling distance >= 5 x Øtool) with BTA system (Boring Trepanning Association) occurs when you produce parts with good productive performance combined with good machining quality. Mechanical industries operate in a context of constant competition, with ever greater technical and economic requirements. This study illustrates the desire of many industrial players (AREVA and CIRTES) and university (LEMTA, Université de Lorraine), to advance in the understanding of machining mechanisms that govern this process. A literature review revealed that this technology offers a vast and relatively unexplored field of investigation and study. The aim of this study is to analyze and modelling the phenomena which occurring in a deep drilling operation. An analysis of the morphology of the chips has introduced a new parameter for assessing the mechanical stresses suffered by the material being machined . The proposed approach allows to define the mechanical stress torsor by integrating the real cutting geometry, for all cut surfaces of active drilling head BTA. The principles of modeling used allow a relatively easy application to many materials and from the identification of a minimum parameters. Original experimental methods have allowed the identification of parameters and adjust and examine the validity of modeling. The limitations of the law of behavior have been used in evidence, and the prospects for further studies have been proposed. Nevertheless, all the results of this study open, modestly, interesting perspectives, especially in the field of helping for the choice of optimum cutting parameters, and help in the understanding of the physical phenomena of the cut

Le micro-fraisage (diamètre fraise < 1 mm) permet l’usinage précis de structures en 3D, à des dimensions micrométriques, dans desmatériaux d’ingénierie, se plaçant aux frontières de deux mondes : d’une part, le fraisage traditionnel appelé « fraisage macro » et d’autre part,la micro-fabrication et ses techniques dites de « salle blanche ».L'étude innovante porte sur le micro-fraisage d’aciers inoxydables 316L avec des micro-fraises cylindriques en carbure de tungstèneavec un équipement industriel (machine outil commercialisée et non optimisée) permet d’accentuer les nombreuses difficultés technologiquesliées à la mise en oeuvre du micro-fraisage et d’effectuer directement un transfert de compétences vers l’industrie. L’acier 316L(biocompatible, réputé de difficilement usinable) n’a jamais été étudié en micro-fraisage.L’étude aborde, au travers de neufs ratios caractéristiques du micro-fraisage, les problématiques de choix de moyens et de méthodespour caractériser la technique du micro-fraisage.Après analyses des paramètres de l’étude et des caractérisations des usinages, la définition géométrique optimale d’une micro-fraiseinnovante est proposée. Sa tenue en service est validée par des tests en usinage dans l’acier 316L, répondant ainsi, à une problématique decoupe négative à basse vitesse de coupe avec des effets d’échelle du matériau.Une originalité de l’étude est d’aborder l’effet de la population inclusionnaire visant à améliorer l’usinabilité. En comparant lesrésultats obtenus par micro-fraisage de 2 nuances d’acier 316L, la population inclusionnaire de l’acier 316L n’est pas identifiée comme unfacteur améliorant l’usinabilité à l’échelle de la coupe micro. / The micro-milling ( tool diameter < 1 mm) target the precise machining of 3D structures to micrometric dimensions, in engineeringmaterials, to be placed at the borders of two worlds : the one hand , the traditional milling called "macro milling" and other hand, the microfabricationand its so-called "clean room" techniques.The innovative study focuses on the micro-milling of 316L steel with carbide micro end mills with industrial equipment (machine toolmarketed unoptimized) can caricature the many technological challenges related to the implementation of the micro-milling and make a directtransfer of skills to the industry. 316L steel (biocompatible, reputed difficult to machine) has never been studied in micro-milling.The study looks at ratios through new features of the micro-milling, the problems of choice of means and methods to characterizemicro-milling.After analysis study parameters and machined parts, the optimal geometric definition of an innovative micro end mill is proposed.Service behavior is validated by testing machining in 316L steel, responding to a question of negative cutting with low cutting speeds andscale effects of the material.An originality of the study is to address the effect of the inclusion population to improve machinability. Comparing the resultsobtained by micro-milling two 316L steel grade, the inclusion population of 316L steel is not identified as a factor improving themachinability cutting at micro scale.

Thèse ou mémoire avec insertion d'articles. / Devant l'urgence climatique, l'aménagement forestier peut contribuer à la lutte contre les changements climatiques, notamment par la production de produits du bois qui stockent du carbone hors de l'atmosphère pendant de longues périodes en substituant par le fait même des matériaux plus polluants. La coupe partielle, un procédé sylvicole qui tarde à être utilisé plus largement au Québec, fait tranquillement ses preuves en forêt boréale quant à son potentiel pour l'adaptation et l'atténuation des changements climatiques. Le but de ce mémoire était d'évaluer la capacité à créer des produits du bois de haute valeur et de longue durée de vie de deux types de coupe partielle en forêt boréale. Plus spécifiquement, le but était de comparer l'effet de la coupe progressive irrégulière à couvert permanent et de l'éclaircie commerciale sur le potentiel de croissance des arbres résiduels et leur rendement en produits du sciage et ce, par rapport au scénario de référence de la coupe totale. En utilisant la Forêt Montmorency comme étude de cas, le modèle 3-PG a été utilisé pour simuler la croissance et la coupe de peuplements monospécifiques de sapin baumier (Abies balsamea (L.) Mill) et d'épinette blanche (Picea glauca (Moench) Voss). Grâce à StatSAW, l'assortiment de produits du bois issu des récoltes a été établi selon les différents traitements de récolte. Les résultats les plus marquants ont été observés sur le diamètre quadratique des tiges résiduelles. Pour le sapin baumier, des gains de 1,9, 2,5 et 3,3 cm ont été observés lors de la coupe finale à 70 ans pour les peuplements ayant subi à 30 ans des éclaircies commerciales de 25%, 33% et 40% de la surface terrière respectivement, par rapport à des peuplements non traités. Pour des peuplements soumis à la coupe progressive irrégulière à couvert permanent, un gain de 5,6 et 3,3 cm a été observé comparativement au contrôle à 70 et 90 ans. Pour l'épinette blanche, des gains de 1,8, 2,5 et 3,2 cm ont été observés pour l'éclaircie commerciale à 25%, 33% et 40% respectivement. Pour la coupe progressive irrégulière à couvert permanent, un gain de 5,1 et 3,6 cm a été observé comparativement au contrôle à 70 et 90 ans. Malgré les gains significatifs en diamètre chez les deux essences, l'assortiment de produits du bois cumulatif des scénarios avec éclaircie commerciale à la suite de la coupe finale à 70 ans ne s'est pas distingué du scénario de référence de la coupe totale (sans éclaircie). Cependant, dans une perspective de récolte à perpétuité, la coupe progressive irrégulière à couvert permanent a démontré le meilleur potentiel de génération de produits du bois de grandes dimensions pouvant stocker du carbone sur de longues périodes. En effet, la transition vers une structure de peuplement irrégulière, complétée à 90 ans, devrait permettre des coupes subséquentes qui affichent les meilleures proportions de sciage, avec les dimensions de produits les plus grandes ayant un fort potentiel d'utilisation en construction, où les meilleurs temps de demi-vie sont observés. Dans l'optique de mieux établir le potentiel des coupes partielles à lutter contre les changements climatiques, un bilan carbone complet serait nécessaire, en incluant l'ensemble de la dynamique du carbone de l'écosystème et des produits du bois. Également, il serait nécessaire d'évaluer l'impact de perturbations naturelles, comme la tordeuse des bourgeons d'épinettes, sur les peuplements issus de ce type de coupe. Somme toute, les résultats suggèrent que les coupes partielles, notamment celles faisant partie d'un système de récolte à couvert permanent, ont un fort potentiel de lutte contre les changements climatiques. / In the face of the climate emergency, forest management can contribute to the fight against climate change, notably through the production of wood products that sequester carbon out of the atmosphere for long periods of time, thereby substituting more polluting materials. Partial cutting, a silvicultural process that has been slow to be used more widely in Quebec, is gradually proving its potential in the boreal forest for adaptation and mitigation of climate change. The purpose of this thesis was to evaluate the performance of two types of partial cutting to create high quality wood products with long half-life cycle in the boreal forest. More specifically, the goal was to compare the effect of continuous cover irregular shelterwood and commercial thinning on growth potential of residual stems and wood product yield compared to the control scenario of clearcutting only. Using the Montmorency Forest as a case study, the 3-PG model was used to simulate the growth and harvesting of monospecific stands of balsam fir (Abies balsamea (L.) Mill) and white spruce (Picea glauca (Moench) Voss). Using StatSAW, the assortment of wood products from harvests was estimated for the different treatments. The most striking results were observed on the quadratic diameter of residual stems. For balsam fir, a gain of 1.9, 2.5 and 3.3 cm was observed following commercial thinning of 25%, 33% and 40% of the basal area respectively. For stands submitted to the continuous cover system, a gain of 5.6 and 3.3 cm was observed compared to the control at 70 and 90 years. For white spruce, a gain of 1.8, 2.5 and 3.2 cm was observed for the commercial thinning at 25%, 33% and 40% respectively. For the continuous cover, a gain of 5.1 and 3.6 cm was observed compared to the control (clearcut only) at 70 and 90 years. Despite the significant gains in diameter in both species, the cumulative assortment of products of the commercial thinning at the final cut of 70 years did not differ from the reference of clearcutting (without thinning). However, from a perpetual harvesting perspective, continuous cover irregular shelterwood showed the best potential for generating larger-sized wood products that can store carbon over long periods. The last harvest, which would be repeated in subsequent cuts, shows the highest sawnwood proportions, with the largest product sizes having high potential for construction use, where the longest half-life times are observed. To better establish the potential of partial cuts to address climate change, a full carbon budget would be required, including the carbon dynamics in ecosystems and wood products. Also, it would be necessary to evaluate the impact of natural disturbances, such as the spruce budworm, on stands treated by this type of harvesting. In conclusion, the results suggest that partial cuts, particularly when included in a continuous cover harvest system, have a strong potential to contribute to climate change mitigation.

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