This work discusses in detail the history of, and processes associated with the construction of baroque era trumpets then and now. The work addresses metallurgy, tools, construction methods, and playing characteristics of instruments built with old techniques and modern techniques.

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Au Canada, le secteur du bâtiment émet 17% de toutes les émissions de GES et consomme 50% de toute l'énergie primaire. Dans un contexte de mix énergétique à faible impact environnemental comme celui qui prévaut dans la province de Québec (Canada), une grande partie de ces pourcentages est attribuable à l'énergie intrinsèque. Celle-ci peut représenter jusqu'à 46% de toute l'énergie consommée sur le cycle de vie d'un bâtiment pour une durée de vie de 50 ans. La moitié de ce pourcentage est attribuable à la combinaison de la structure et de l'enveloppe du bâtiment. La plupart des études déjà réalisées ayant comparé différents systèmes d'enveloppe pour un bâtiment résidentiel, ce projet vise à quantifier la contribution des impacts intrinsèques initiaux aux impacts environnementaux du cycle de vie d'assemblages de mur extérieur pour un bâtiment à bureaux situé dans la ville de Québec (Canada). Une analyse du cycle de vie du berceau au tombeau (cradle-to-grave) a été réalisée sur huit assemblages de mur extérieur. Les impacts environnementaux ont été évalués à l'aide du logiciel open LCA, de la base de données ecoinvent et de la méthode d'évaluation des impacts TRACI. L'énergie consommée lors de la phase d'utilisation du bâtiment a été simulée à l'aide du logiciel EnergyPlus. Les résultats indiquent que la contribution des impacts intrinsèques initiaux au cycle de vie des assemblages de mur est de 41% à 66%. Les résultats suggèrent que, dans un tel contexte, les impacts intrinsèques initiaux peuvent devenir la principale source d'impacts environnementaux dans le cycle de vie des assemblages de mur. Les résultats de ce projet feront comprendre aux dirigeants l'importance d'évaluer les impacts intrinsèques lors des premières étapes de la conception des bâtiments dans l'objectif de construire des bâtiments plus durables. Ces résultats guideront également les praticiens dans la sélection d'assemblages muraux plus durables en fonction de leurs impacts environnementaux. / In Canada, the building sector account for 17% of all GHG emissions and consumes 50% of all primary energy. In the context of a low environmental impact energy mix such as the one prevailing in the province of Quebec (Canada) a large part of these percentages is attributable to embodied energy. In such a context, the embodied energy of building materials can account for up to 46% of a building's life cycle energy over a 50-year service life. Half of this energy corresponds to the combination of the structure and the building envelope. While most studies have compared different residential building systems or wall assemblies, this study aims to quantify the contribution of initial embodied impacts to the environmental impacts of wall assemblies' life cycle for the exterior walls of an office building in Quebec City (Canada). Cradle-to-grave life cycle assessments were conducted on eight wall assemblies. The life cycle assessment impacts were evaluated using openLCA, the ecoinvent database and the TRACI method. Energy use during the building use stage was simulated using EnergyPlus. The results indicate that initial embodied impacts can account for 41% to 66% of all environmental impacts throughout the wall assemblies' life cycle. These results suggest that in a low environmental impact energy mix, the initial embodied impacts can become the dominant source of environmental impacts in wall assemblies' life cycle. The results of this study will help decision makers understand the importance of assessing embodied impacts in the early stages of building design to conceive more sustainable buildings. These results will also guide practitioners in selecting more sustainable wall assemblies based on their environmental impacts.

La conception de l'assemblage plafond-plancher dans un bâtiment en bois peut être un défi en raison de ses aspects multidisciplinaires et des limitations d'espace. En tant qu'un composant du bâtiment, cet espace possède un rôle structural et représente un volume dans lequel passent les systèmes de la mécanique du bâtiment. L'objectif de ce travail est de démystifier l'assemblage plafond-plancher à travers une recherche bibliographique et des entrevues semi-dirigées et de développer ensuite une méthodologie d'optimisation multi-objectif pour une conception optimale de ce sandwich. Le modèle développé intègre tant la partie structurale que les systèmes de la mécanique du bâtiment, dont un but de minimiser l'épaisseur de l'assemblage tout en optimisant le système de ventilation qui passe dedans. L'algorithme NSGA-II est utilisé dans le processus d'optimisation. Une étude de cas sur un assemblage plafond-plancher dans un bâtiment en bois a été réalisée pour évaluer le modèle développé, où trois configurations d'assemblage ont été testées. Dans la première configuration, le réseau de ventilation passe à travers la structure, soit en parallèle aux poutres, soit en les traversant. Dans ce cas, des ouvertures seront nécessaires à condition que le diamètre de la conduite ne dépasse pas 15% de la hauteur des poutres. Dans la deuxième configuration, on considère que les poutres sont renforcées, pour donner une tolérance supplémentaire relative à l'ouverture au niveau des poutres allant jusqu'à 30% de leur hauteur. La troisième configuration est la méthode traditionnelle où aucune ouverture n'est autorisée et le réseau de ventilation passe en dessous de la structure. Pour les trois configurations, deux types de dispositions des gaines de ventilation ont été évaluées. Les meilleures solutions sont présentées sous la forme de fronts de Pareto. L'analyse des résultats montre que l'optimisation de la configuration traditionnelle de l'assemblage donne toujours de meilleures solutions (où l'épaisseur de l'assemblage varie de 0.65 m à 0,87m et la perte de pression varie de 50 Pa à 105 Pa) comparativement aux deux autres configurations. / The design of the ceiling-to-floor assembly in timber buildings can be challenging due to its multidisciplinary aspects, space limitations, and requirements of timber constructions. As a component of the building, this space has a structural role. It ensures the safety and comfort of occupants and represents a volume through which building services systems pass. The objective of this work is to demystify the ceiling-to-floor assembly in timber buildings and to develop a multi-objective optimization method for an optimum design. In order to do this, bibliographical research was carried out in various databases. This step was accompanied by a series of semi-structured interviews with wood construction experts. Then a multi-objective optimization strategy for the ceiling-to-floor assembly was developed. It integrates both structures and building mechanical systems to minimize the thickness of the ceiling-to-floor assembly and optimize the pressure drops in the air distribution system that passes through it. The multi-objective genetic algorithm (NSGA-II) is used in the optimization process. Design variables related to the structure and ventilation network are taken into account. A case study of a ceiling-to-floor assembly in a timber building was carried out to evaluate the developed model, where three assembly configurations were tested: (i) the diameter of an aperture in a beam to let a duct pass is limited to 15% of the beam height, (ii) the aperture diameter limitation is 30% of the beam height, corresponding to a beam with reinforcement, (iii) no apertures are allowed and the ducts are below the beams. Best solutions are presented through the Pareto fronts and the optimal dimensions of the structure and air distribution ducts are generated. For the case study, results show that the optimization algorithm gives better results in terms of thickness and pressure drops in the third configuration where ducts pass through beams (assembly thickness ranges from 0.65 to 0.87 m, pressure drops from 50 Pa to 105 Pa), compared to the configuration where the duct passes through the structure.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Presented in this thesis are the test results of combined processing and mechanical property characterisation studies using a developed cementitious mix reinforced by various fibre types and forms (with short and continuous lengths). The research is aimed to identify new Fibre Reinforced Cementitious (FRC) composites that have post-cracking ductility, much higher flexural strength and higher toughness than the control (matrix) material without reinforcement, and higher than traditional FRC composites. Laboratory work uses two methods to process the green forms, one by novel compression moulding and the other by hand lay-up that were both adapted from the fibre reinforced polymer industry. Results show a reduction in the hand lay-up water/binder ratio of 24 to 41% can be achieved by applying compression moulding with a pressure of 9MPa. One key processing challenge with short recycled milled carbon fibres is to make the mix uniform, even when the volume fraction is low at 2%. Microstructural investigations confirm that the carbon fibres, having mean length of 0.085 mm, always gave a very poor dispersion, and this is due to static electricity causing the fibres to form into balls (5 to 30 mm diameter). Overall, the study with short fibre reinforcements found that, by adding 2% by volume of the polyvinyl alcohol (PVA) fibres, the stress-strain curve exhibits strain-hardening behaviour accompanied by multiple cracking. Furthermore, the flexural properties show the material to possess ductility, toughness and mean strength that, at 13 MPa, is two times higher than the control material. It is observed that the hydrophilic nature of PVA and the fibres surface roughness play a significant role in an increased bonding strength with this short fibre. When introducing continuous fibre reinforcement in the form of fabrics it is shown that the volume fraction of fibres should be no more than 5%. Unsuccessful green form specimens were a consequence of having a higher volume fraction by introducing more fabric layers. Test results show that materials reinforced with carbon fabrics give an FRC material with much improved mechanical properties, in terms of post-cracking strength, strain at peak stress and toughness (energy absorption) at peak stress. Higher overall bond strength might be attributed to an apparent increase in interfacial contact area between fibres and cement matrix and improved mechanical anchoring from the fabric’s construction. Microstructural investigations confirm that good matrix penetrability between the filaments of the tow or bundle is essential in order to maximise the reinforcing efficiency of the fabric. Investigated are two novel methods for modifying the continuous unidirectional carbon fibre reinforcements to improve the overall bond strength, by enhancing matrix penetration through and across the reinforcement plane. In one method the fabric is cut into strips to leave spaces (holes) between parallel reinforcement units for the matrix material to bridge across, while in the second method the fabric receives a surface treatment by immersion in Ethanol alcohol. Test results show that, with compression moulding and the strip form of reinforcement at 5% volume fraction the FRC composite has a flexural strength of 75 MPa. This flexural strength is ten times higher than the measured strength of the control material. The experimental research reported in this thesis shows that to achieve ‘unusual’ composite action and a relative high stress at loss of proportionality requires a continuous fibre reinforcement that can be treated or non-treated. Given the considerable increase in mechanical properties achieved using such fibre reinforcement at 5% the most promising FRC materials require to be further evaluated to find suitable candidates for load bearing products.

This work deals with the preparation, thermo-hydraulic characterisation, and performance analysis of silica gel coated highly conductive surface enhancing structures to be used as tube inserts in a prototype of an innovative water-cooled sorption rotor. The candidate inserts under investigation comprise highly porous aluminium foam inserts, twisted-in wire brushes, and flocked structures, that are investigated for their flow impedance, heat transfer performance, and cyclic dehumidification performance. The conducted analysis comprises experimental testing of insert specific pressure drop and heat transfer performance in a purpose built test rig, that led to the preselection of the foam structures and a twisted-in aluminium wire brush insert for desiccant coating and further investigation. Cyclic heat and mass transfer tests were performed in a purpose-built small-scale test rig, that simulated the dehumidification process of a desiccant rotor with and without employing water-cooling. The experimental analysis is complemented by a numerical investigation of the cyclic heat and mass transfer performance of the brush and metal foam type structures, modelled as two-dimensionally axis-symmetric porous media. The geometry based functions of the insert specific flow characteristics are derived from two- and three-dimensional pore scale computational fluid dynamics models, that are calibrated against experimental data. The validity of fundamental modelling assumptions was confirmed by a decent agreement between numerical and experimental steady-state heat transfer results. The heat and mass transfer investigation showed that the investigated structures were capable of effectively removing heat during the dehumidification half-cycle. The thermal mass was shown to be a critical design parameter in achieving acceptable dehumidification performance.

The objectivc of this research was to determine the in-plane shear stiffness and strength of a reinforced concrete sprecimen, which had first been cracked in uniaxial tension. This information could then lead to a more accurate analysis or reinforced concrete structures using the finite clement method. Tests were devised that enabled the effects of aggregate interlock and of dowel action in slab type specimens to be studied independently. As the aggregate interlock and dowel action specimens were similar and were loaded in the same way, a direct comparison of the test results could be made. The composite effects of aggregate interlock and dowel action were then studied by applying the same shear loading to cracked reinforced concrete specimens. The shear stiffness and strength due to aggregate interlock were typically found to be two to four times as great as those due to dowel action. It was also observed that the crack in the aggregate interlock tests tended to widen as shear slip occurred. This is an effect which has received very little attention in the past. The stiffness normal to the crack that restrains crack widening, and the initial crack width were both observed to have a significant influcnce on the aggregate interlock shear stiffness. The behaviour of the reinforced concrete specimens was similar to that which was expected from the results of the dowel action and aggregate interlock tests, if the additional effects of local bond were LikclI into consideration. Several analytical models of the micro mechanisms of shear resistance within the specimens were studied and formulae were derived to predict their behaviour. A matrix equation for the material properties for cracked concrete was derived and used in a finite clement analysis in an attempt to model the behaviour of a reinforced concrete structure.

The Finite Element and Boundary Element Methods are both well established numerical techniques for analysing a wide range of engineering problems. In the present thesis these numerical techniques are used for obtaining a more realistic picture of various characteristics of concrete gravity dams. The present work addresses the behaviour of gravity dams under static loading, and the developed analysis procedure/computer package can cater for a wide range of dam characteristics including: the three-dimensional behaviour of a gravity dam-foundation-abutments system; the non-linear behaviour of a dam and foundation materials; the sequential construction of a dam and impounding of the reservoir loading on the structure; the effect on stresses of interfaces and joints existing between a dam and its foundation, and in the body of a dam itself; the action of pore water pressure within the foundation, at the dam-foundation interface, and in the body of a gravity dam; etc. Using the purpose written computer package which can cater (in an efficient and accurate way) for the influence of all such factors, mathematical programming methods are, then, used to produce a powerful tool for the shape optimisation of gravity dams leading to safe, functional and economical solutions to the problem. In the course of developing the computer program, much care has been exercised as regards the appropriate selection of the finite element types, mesh configurations and mesh densities, in order to reflect (in an efficient fashion) the variation of stress gradients in the body of a gravity dam. In order to reduce high costs associated with a full three-dimensional analysis, a rather efficient method is developed which enables one to carry out equivalent twodimensional computer runs which will effectively simulate the actual three-dimensional behaviour of gravity dams in, for example, narrow valleys. The proposed approach reduces the dimensionality of an actual problem by one, thus, eliminating the main disadvantage of the finite element method in terms of high solution costs for threedimensional problems. As a result, the proposed method makes the solution procedure highly cost effective. By coupling the finite element-boundary element (FEBE) techniques, which can cater for the material non-linearities in the appropriate regions of the foundation, an attempt is made to by-pass the individual disadvantages of both these numerical techniques. It has, then, been possible to exploit the advantages of reducing the dimensionality of the foundation region by one using the boundary element technique, and, hence, come up with significant savings in terms of computer running times. Anisotropic tangent constitutive models for plain concrete under a general state of biaxial static monotonic loading for, both, plane-stress and plane-strain states of stresses are proposed which are simple in nature, and use data readily available from uniaxial tests. These models have been implemented into the computer program which is, then, used to investigate the influence of the step-by-step construction of the dam and the sequential impoundment of the reservoir loading on the state of stresses. The non-linear program is also used to analyse various characteristics of Bratsk concrete gravity darn (in Russia). The correlations between the numerical results and extensive field measurements on this darn, have been found to be encouraging. Isoparametric quadratic interface finite elements for analysing the darnfoundation interaction problem have also been developed. These elements have zero thickness and are based on an extension of the linear interface elements reported by others. The numerical problems of ill-conditioning (usually associated with zero thickness elements) are critically investigated using test examples, and have been found to be due to inadequate finite element mesh design. Non-linear elastic tangent constitutive models for simulating the shear stress-relative displacement behaviour of interfaces have also been developed, and are used to analyse the effects of including interface elements at the dam-foundation region of contact. It is shown that the inclusion of interface elements in the numerical analyses of the dam-foundation system leads to rather significant changes in the magnitudes of the critical tensile stresses acting at the heel of the dam, which have previously been evaluated (by others) using a rigid dam-foundation interconnection scheme. Effects of pore water pressure, acting as a body force throughout the foundation, the dam-foundation interface and the body of a gravity dam, are also critically studied, with the pore pressure values predicted by seepage analysis. Using an extensive set of numerical studies, a number of previously unresolved issues as regards the influence of pore pressures on the state of stresses are clarified. The effect of drainage on the state of stresses within the body of a dam is investigated, and an insight is also given into the effect of the uplift acting at the lift lines between successive layers of Roller Compacted Concrete (ReC) dams. A shape optimisation procedure for gravity dams based on the penalty function method and a sequential unconstrained minimisation technique is also developed. A number of shape optimisations of idealised gravity dams are carried out in order to compare the numerical results with previously available analytical solutions. The present work also caters for the effects of foundation elasticity and uplift on the optimal shape of a gravity dam. A numerical example is provided covering the shape optimisation of a hollow gravity dam. Finally, the shape optimisation of an actual dam (i.e. Tvishi gravity dam in Georgia) using the presently proposed procedures is carried out with the fmal results compared with those available from the project design team. Wherever possible. numerical outputs have been checked against available small or full scale test data or previously reported closed form solutions. Throughout this thesis very encouraging correlations between the present predictions and such experimental and theoretical data have been obtained.

In the construction sector, capturing the building product in a single information model with good interoperable capabilities has been the subject of much research efforts in at least the last three decades. Contemporary advancements in Information Technology and the efforts from various research initiatives in the AEC industry are showing evidence of progress with the advent of building information modelling (BIM). BIM presents the opportunity of electronically modelling and managing the vast amount of information embedded in a building project, from its conception to end-of-life. Researchers have been looking at extensions to expand its scope. Sustainability is one such modelling extension that is in need of development. This is becoming pertinent for the structural engineer as recent design criteria have put great emphasis on the sustainability credentials in addition to the traditional criteria of structural integrity, constructability and cost. Considering the complexity of nowadays designs, there is a need to provide decision support tools to aid the assessment of sustainability credentials. Such tools would be most beneficial at the conceptual design stage so that sustainability is built into the design solution starting from its inception. This research work therefore investigates how contemporary process and data modelling techniques can be used to map and model sustainability related information to inform the structural engineer’s building design decisions at an early stage. The research reviews current design decisions support systems on sustainability and highlights existing deficiencies. It examines the role of contemporary information modelling techniques in the building design process and employs this to tackle identified gaps. The sustainability of buildings is related to life cycle and is measured using indicator-terms such as life cycle costing, ecological footprint and carbon footprint. This work takes advantage of current modelling techniques to explore how these three indicators can be combined to provide sustainability assessment of alternative design solutions. It identifies the requirements for sustainability appraisal and information modelling to develop a requisite decision-support framework vis-à-vis issues on risk, sensitivity and what-if scenarios for implementation. The implementation employed object-oriented programming and feature modelling techniques to develop a sustainability decision-support prototype. The prototype system was tested in a typical design activity and evaluated to have achieved desired implementation requirements. The research concludes that the utilized current process and data modelling techniques can be employed to model sustainability related information to inform decisions at the early stages of structural design. As demonstrated in this work, design decision support systems can be optimized to include sustainability credentials through the use of object-based process and data modelling techniques. This thesis presents a sustainability appraisal framework, associated implementation algorithms and related object mappings and representations systems that could be used to achieve such decision support optimization.