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The building sector accounts for more than 50% of global energy consumption. This consumption has been increasing steadily over the last thirty years. The environmental impact of energy consumption in this sector is constantly changing despite the recommendations made during the COPs. These findings are valid for metropolitan France and also for Madagascar. Beyond the control of energy consumption, during the operating phase of a built space, we must also take into account the environmental impacts of the construction phase, particularly with regard to climate change indicators, resource management and pollution. This thesis is based on three concepts. First, it is about the analysis of material flows around their technical characteristics and their environmental and economic impacts during the construction of the built space. In a second step, our analysis focuses on the analysis of energy flows in order to know the energy and environmental signature of the functioning of the built space and the implementation of a time file reflecting the characteristics of energy consumption (Daily and annual consumption profile). Finally, we also discuss the problem of managing the distribution of electrical energy in a built-up area in order to size an renewable energy production system and a storage system and to smooth the consumption curve at the level of the distribution network.; Le secteur du bâtiment participe à hauteur de plus de 50% de la consommation d’énergie à l’échelle mondiale. Cette consommation ne cesse d’augmenter depuis ces trente dernières années. L’impact environnemental de la consommation d’énergie au niveau de ce secteur est en évolution permanente malgré les recommandations prises durant les COP. Ces constatations sont valables pour la France métropolitaine et aussi pour le cas de Madagascar. Au-delà de la maitrise de la consommation d’énergie, en phase de fonctionnement d’un espace bâti, nous devons également prendre en compte les impacts environnementaux de la phase de construction notamment en ce qui concerne les indicateurs de changement climatique, des maitrises de ressources et de la pollution. Cette thèse s’articule autour de trois concepts. En premier lieu, il s’agit de l’analyse des flux matière autour de leurs caractéristiques techniques et de leurs impacts environnementaux et économiques lors de la construction de l’espace bâti. Dans un second temps, notre analyse se focalise sur l’analyse de flux d’énergie en vue de connaitre la signature énergétique et environnementale du fonctionnement de l’espace bâti et de la mise en œuvre d’un fichier horaire traduisant les caractéristiques de la consommation d’énergie (Profil de consommation journalier et annuel). En dernier lieu, nous abordons également la problématique du pilotage de la distribution de l’énergie électrique dans un espace bâti en vue de dimensionner un système de production d’EnR et un système de stockage et de lisser la courbe de consommation au niveau du réseau de distribution.

A full analytical model of a beam–plate system has been produced in order to study the distribution of vibration energy and energy flow in beams and rods under simple but realistic excitation conditions. Axial and flexural vibrations are only analysed. Using the developed model as well as energy formulae presented in a companion paper some characteristic features of energy distribution in thin beams/rods have been identified which can be considered as universally applicable. It has been found that axial vibrations, often neglected, may be of the same importance with respect to energy and energy flow as flexural vibrations. Moreover, axial beam vibrations may provide an efficient mechanism of energy transfer to the adjacent sub-systems. Realistic boundary conditions may result in wave conversion which in turn may reverse the flow of energy of either axial or flexural vibration toward the source. The frequency-averaged net power consumed by the beam sub-system was found to depend largely on damping, contrary to the total input power to the system which stays fairly insensitive to it. The energy sharing between the beam and the connected plate was found to depend little on the amount and distribution of damping within the system providing the coupling between the two is strong. Finally, simulation of measurements of energy flow as well as of absorption/reflection/transmission energy coefficients of incorporated joints was shown to be affected to a large degree by beam damping which is often disregarded in experimental work.

Generic features of energy and energy flow in thin rods and beams are investigated. Full equations of energy density and energy flow are formulated in terms of wave amplitudes. The differential equations for energy and energy flow are also formulated which are similar but not identical to some found earlier. The relationship between the power input and global kinetic and potential energies has been applied to rods and beams which gives easy access to their global energy. The present study is focused on semi-infinite rods and beams, and in particular, at the distribution of kinetic and potential energies within the section between the excitation and the end positions. A study of a finite beam system is presented in a companion paper. Both force and moment-type excitations are considered. It is shown that long finite beams closely match equivalent semi-infinite beams, where frequency band-averaged energy characteristics are concerned. Similar equivalence with infinite beams was found not to hold. It is further demonstrated that, unlike the kinetic energy density, the potential energy density exhibits a jump at the excitation point of a rod or a moment-driven beam. The damping was shown to reduce the jump in potential energy across the excitation point, but in turn increases the frequency range of strong power input to the end section.