This thesis proposes that the concept 'permanence' is relevant at the beginning of the twenty first century. It examines why the term, while perhaps pertinent in addressing the disposability of architecture in Western society, seems anachronistic. The study reviews the seeming inaccessibility of the term in its contested and plural interpretations, and reviews problems in its definition and relevance. <br /><br /> A close examination of definitions, interpretations and contemporary approaches is provided in order to create a conceptual framework that reveals complex implications of the term. Four strategies for understanding the concept are offered: 'realms versus modes', definitions, a distillation of four positions relating to permanence, and an inquiry into contemporary issues relating to the concept. 'Absolute' and 'relative' realms illuminate a scope for permanence, and 'static' and 'dynamic' modes are discussed. A series of definitions are reviewed that reveal nuance in implications. An analysis of four essays on permanence is included, one from the beginning of the twentieth century and three from the end. This section reveals a series of conflicts relating to the way contemporary Western society uses and understands the term. <br /><br /> Permanence within architecture is widely associated with the Vitruvian definition of <em>firmitas</em>: mass and solidity crafted to endure eternally. Vitruvius' employment of 'permanence' is used as a grounding definition and a fundamental reference for the term's evolution into contemporary usage. In observing the endurance of the original Vitruvian term today, a disconnect becomes evident: absolutism in a society defined by relativity. This thesis argues for the critical significance of the term at a pivotal point in history in addressing the problem of disposable architecture on both a cultural and ecological level. Final open-ended questions are raised that consider staggering construction and demolition waste statistics, implying that permanence could play a significant role in effective responses to a global environmental crisis.

This thesis proposes that the concept 'permanence' is relevant at the beginning of the twenty first century. It examines why the term, while perhaps pertinent in addressing the disposability of architecture in Western society, seems anachronistic. The study reviews the seeming inaccessibility of the term in its contested and plural interpretations, and reviews problems in its definition and relevance. <br /><br /> A close examination of definitions, interpretations and contemporary approaches is provided in order to create a conceptual framework that reveals complex implications of the term. Four strategies for understanding the concept are offered: 'realms versus modes', definitions, a distillation of four positions relating to permanence, and an inquiry into contemporary issues relating to the concept. 'Absolute' and 'relative' realms illuminate a scope for permanence, and 'static' and 'dynamic' modes are discussed. A series of definitions are reviewed that reveal nuance in implications. An analysis of four essays on permanence is included, one from the beginning of the twentieth century and three from the end. This section reveals a series of conflicts relating to the way contemporary Western society uses and understands the term. <br /><br /> Permanence within architecture is widely associated with the Vitruvian definition of <em>firmitas</em>: mass and solidity crafted to endure eternally. Vitruvius' employment of 'permanence' is used as a grounding definition and a fundamental reference for the term's evolution into contemporary usage. In observing the endurance of the original Vitruvian term today, a disconnect becomes evident: absolutism in a society defined by relativity. This thesis argues for the critical significance of the term at a pivotal point in history in addressing the problem of disposable architecture on both a cultural and ecological level. Final open-ended questions are raised that consider staggering construction and demolition waste statistics, implying that permanence could play a significant role in effective responses to a global environmental crisis.

Ce travail concerne la modélisation numérique et expérimentale de la variabilité des propriétés thermo-hydriques de matériaux cimentaires en vue de l’évaluation de son impact sur la prédiction du comportement hygrothermique de parois de bâtiments. Une approche probabiliste qui prend en compte la variabilité spatiale des propriétés de matériaux lors des transferts couplés de chaleur et d’humidité a été développée. Elle est basée sur la génération, par la décomposition modale de Karhunen-Loève, de champs aléatoires spatialement corrélés. Une implémentation d’un modèle de transfert hygrothermique dans un code de simulation numérique a été ensuite réalisée en adoptant cette démarche stochastique. Cette dernière, qui considère comme variables d’entrée des champs aléatoires, permet de quantifier l’incidence de cette variabilité sur le comportement hygrothermique d’une paroi de bâtiment. Une étude préalable, dédiée à l’évaluation de l’incidence de la variabilité aléatoire du coefficient de diffusion, a été entreprise en considérant une variabilité de ±30% pour un mortier et de ±20% pour un BHP suivant une loi de distribution normale. Aussi, nous avons relevé un certain nombre d’incertitudes possibles de la teneur en eau à saturation tout en montrant leurs effets sensibles sur le résultat de la prédiction du comportement hygrothermique. Ces études ont permis de mettre en exergue l’importance de la prise en compte des incertitudes sur les données du matériau lors des simulations numériques des transferts hygrothermiques. Sur le plan expérimental, une campagne d’évaluation de la variabilité spatiale des paramètres les plus influents a été menée. Cette campagne a été réalisée sur un voile de dimension 2x1,2 m fabriqué au laboratoire. À l’issue de ce programme expérimental, l’espérance, la variance et la longueur de corrélation des propriétés étudiées (porosité à l’eau, perméabilité à la vapeur, isotherme de sorption et perméabilité au gaz) ont été déterminées. Ces trois paramètres sont indispensables pour la bonne mise en œuvre de la décomposition de Karhunen-Loève. Aussi, une autre campagne de caractérisation expérimentale a été menée sur des pâtes de ciment, mortiers et béton. Elle a été divisée en trois grandes parties selon les propriétés étudiées : (i) Les propriétés microstructurales et d’hydratation où l’on retrouve les mesures des porosités à l’eau et au mercure ainsi que les distributions de la taille des pores et une analyse de l’effet du taux d’hydratation de matériaux cimentaires sur leurs propriétés hygrothermiques. (ii) Les propriétés hydriques : dans cette partie, une analyse sous différents angles (évolution en fonction de l’âge des matériaux, en fonction de la température, effet des constituants des matériaux, etc.) a été réalisée sur les isothermes de sorption et sur la perméabilité à la vapeur d’eau. (iii) Les propriétés thermiques où des mesures de conductivités thermiques et de chaleurs spécifiques ont été effectuées. Les résultats de l’étude ont mis en exergue les limites des approches déterministes suite à leurs confrontations avec les résultats obtenus par l’approche probabiliste, mise en œuvre dans le cadre du présent travail. / This study deals with the experimental and the numerical modeling of the variability properties of cement based materials to evaluate their effects on the prediction of hygrothermal behavior of building envelops. A probabilistic approach taking into account the spatial variability of the materials properties during the coupled heat and mass transfer has been developed. It is based on the generation of spatially correlated random fields by the Karhunen Loève decomposition. The stochastic model’s program has been implemented in a numerical simulation code. Using this tool that considers the input variables as random fields, the impact of this variability on the hygrothermal behavior of building envelops was quantified. A prior study dealing with the assessment of the effect of the diffusion coefficient random variability was carried out by considering a variation of ±30% for mortar and ±20% for high performance concrete (HPC) according to a normal distribution. Also, we have identified some possible uncertainties of the water content at saturation and showed their significant impact on the prediction of hygrothermal behavior of the material. These studies highlight the importance of considering the data uncertainties of building materials during numerical simulation of hygrothermal transfers. At the experimental level, the spatial variability of the most influential parameters was evaluated. It was carried out by manufacturing a concrete wall in lab. At the end of this experimental program, the expected value, standard deviation and the correlation length of the studied properties (water porosity, water vapor permeability, sorption isotherm and gas permeability) were determined. These three parameters are important for the successful implementation of Karhunen Loeve decomposition. Also, another experimental program was conducted on cement pastes, mortars and concrete. It was divided into three parts according to the studied properties:(i) Hydrations and microstructural properties which include the measurement of water and mercury porosity, the pore size distributions and an analysis of some techniques for stopping cement hydration.(ii) Hydric properties: where an analysis of the sorption and the water vapor permeability was performed considering their evolution with materials ages, temperature…(iii) Thermal properties where measurement of specific heat and thermal conductivity were performed. The result of the study highlighted the limits of deterministic approaches after their confrontation with the obtained results using the probabilistic one developed in this work.

Nowadays the attention to the utilization of secondary raw materials as a component of building materials is being paid to in the Czech Republic and in the world. This thesis deals with possibilities of using secondary raw materials as partial cement substitutes in industrial floors. The aim of this thesis is to verify the influence of cement substitution amount with secondary raw materials and their fineness of grinding on the properties of the floor surface in time and on its structure. On the basis of the acquired knowledge, the influence of the pre-treatment of the secondary raw material on the properties of the floor ceiling with an emphasis on the economic aspect was assessed. After evaluating the results, some substitution of cement in the floor screed with secondary raw materials is beneficial. The significant influence of more intensive milling of the floor screeds base on the parameters of the final floor screed was not confirmed. It seems, that it is possible to achieve very good results even when using secondary raw materials with a lower percentage of fine particles. This brings together the economic benefits of lowering the cost of a lower dose of expensive cement by using cheaper secondary raw materials, because pre-treatment of such materials does not require the use of a large amount of energy.