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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

The use of organic materials for building and implications for the environment : a study of Dar-es-Salaam, Tanzania

Sinda, Sinda Hussein January 1997 (has links)
No description available.
92

Building information modelling for sustainability appraisal of conceptual design of steel-framed buildings

Oti, Akponanabofa Henry January 2014 (has links)
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.
93

An investigation into the parameters that contribute to the gap between the designed and as-built thermal performance of British housing

White, Jennifer A. January 2014 (has links)
The UK Government has placed the need to reduce national energy demands and carbon emissions at the forefront of the political agenda, with a commitment made to meet EU targets of 20% reductions in greenhouse gas emissions and primary energy consumption, alongside a 20% improvement in overall energy efficiency, across all EU Member States, by 2020. Building performance has been identified as a key area where significant progress towards meeting these ambitions can be made. It is fundamental to ensure that the building fabric of a property functions correctly in order to achieve high levels of thermal effectiveness, which should result in lower energy demands and carbon emissions. However, research to date shows that a gap exists between predicted and actual performance levels. This research utilises the dwelling Heat Loss Coefficient (HLC) as a common output in design stage and post-construction evaluation techniques, that can be used to compare predicted and measured fabric performance. The Standard Assessment Procedure (SAP), coheating tests, air pressure tests and thermal imaging are used to evaluate in-situ buildings. Sensitivity analysis and controlled conditions experiments are utilised in order to investigate the reliability of the assessment techniques used. The key findings from the study include the demonstration, through novel coheating test, that post-installation mechanically ventilated heat recovery (MVHR) system efficiency levels can have a pronounced effect on the measured HLC, and, in conjunction with use of assumed theoretical efficiency levels, can cause divergence in theoretical and measured data of 10-15%. This can largely be resolved through correct design, installation and commissioning. Environmental conditions, both notional and site-specific, can also cause divergence in the HLC data, including wind speed (15%) and solar gains (10-26%). In addition, it has been shown that, when considering thermal bridging values, inaccurate calculation at the design-stage and poor attention to detail during construction could cause underperformance in this element by up to 50%. This is of significance as there are currently no mandatory procedures to assess post-construction compliance with thermal bridging levels specified within the UK Building Regulations.
94

Exploring a best practice approach to operability and maintainability of low carbon buildings in the UK

Frank, Owajionyi L. January 2014 (has links)
Growth in technological advancement was to humanity a mixed blessing. While it provided comfort and improved quality of life, it also increased the demand for energy to drive them. This increase in energy usage, particularly from fossil fuel sources is widely understood to be responsible for the critical environmental problems in the world (Climate Change). Mitigating and adapting to this anthropogenic induced consequence created the need for varying innovative and new low carbon and renewable technologies which are gradually replacing the traditional high fossil fuel driven systems in buildings. Presently in the UK, every new building is expected to be low carbon and energy efficient; operated in such a manner as to use no more fuel and power than is reasonable in the circumstances. However, it is widely believed that construction underperforms in terms of capacity to deliver value. Clients and end-users of these buildings appear not to be getting long term value for their investments. Much attention has also not been given to how these new and innovative technologies can be operated and maintained long into the future. Recent researches also underpin the fact that the wide information gap existing between designers and building end-users is one of the factors responsible for the underperformance. This research therefore sought to explore a best practice approach that could bridge this information gap, and ensure that low carbon buildings are efficiently operated and maintained long into the future, particularly as the UK built environment moves closer to its zero carbon targets of 2016 and 2019. The research methodology involved triangulation (a mixed-method research approach), thus maximising the chances of benefiting from the strength of each of qualitative and quantitative methods. Interviews, surveys and case studies were employed. Post occupancy evaluation method was also used for the key case study. Findings indicate that there is a need for change in the way low carbon buildings are delivered to the end-users; that a properly prepared operation and maintenance (O&M) manual is indispensable in the effective and efficient operation and maintenance of low carbon buildings, and that it will be good practice to bring in the O&M team early to the design process. The study also suggested that designers be required to prove ‘life-cycle operability and maintainability’ of their designs before they are constructed. To ensure this desired cultural and process change in project delivery, a Maintainability and Operability Integrated (OMI) Design and Construction Process Model is proposed. The model was developed using the proposed RIBA 2013 revised Outline Plan of Work and drawing lessons from the New Product Development (NPD) process used by the manufacturing sector and other construction industry models. A validation test was conducted by means of a focus group, populated by top management officials of the University of Nottingham Estates Office, which has been actively involved in the procurement and management of myriads of low carbon buildings. Feedbacks from the validation test indicate that the proposed OMI Process Model was a well thought out idea which is practicable and capable of addressing the shortfall within the existing processes to deal with the O&M issues raised by the use of new and innovative low carbon technologies.
95

Development of fully composite steel-concrete-steel beam elements

Coyle, Neil Robert January 2001 (has links)
Steel-Concrete-Steel (SCS) composite construction consists of two relatively thin steel plates with the space between filled with concrete. Various forms of this construction exist, using overlapping shear studs and single bar connectors to provide shear reinforcement to the concrete and provide a shear transfer at the interface. The problem with current systems that rely purely upon shear studs or bar connectors is that they are prone to slip between the steel faceplates and concrete core. This slip leads to a loss of composite action causing a loss of stiffness and a reduced fatigue life. An extensive experimental programme consisting of 32 beam specimens and 34 other small scale specimens formed the basis for the study of the behaviour of surfaced SCS specimens under a variety of load conditions. The results of this test program showed that surfaced SCS specimens behaved in a more composite manner. This increase in composite action manifested itself in a number of ways. • Reduced slip between steel plate and concrete core • Increased stiffness of specimen • More even crack distribution This extensive experimental study was backed up with an analytical study to understand and predict the behaviour of the surfaced SCS elements. This study has led to a new method of predicting the capacity of such sections, to a greater degree of accuracy than current methods allow. Further to this a FE parametric study was carried out to investigate the sensitivity of the elements to changes in the main geometrical and material variables.
96

The planning and design of mental health treatment centres

Crews, Joseph MacNeal January 1999 (has links)
This research thesis was developed as a planning and design reference for mental health treatment centres. This text is intended to assist planners, designers, and health practitioners to optimize patient health and comfort by providing suitable environments to facilitate care and treatment. This thesis examines and provides guidance on security issues, environmental design, the cognitive environment, and site development. Sample facility plans are also provided to demonstrate the design principles advocated. The foreword examines the historical background of mental health treatment facilities in relation to the context of care. The continuing problem of the alienating and dehumanizing effects of psychiatric hospitals on patients is also addressed. Security requirements are investigated in relation to patients' rights and personal needs. This text also examines related fire safety requirements and design measures to minimize the risks of suicides, self injuries, and assaults. Environmental design issues, including lighting, color, acoustics, construction materials, air quality, and spatial relationships, are examined in relation to mental and physical health. Cognitive issues such as wayfinding, mental maps, symbolism, and perceptions of physical environments and architectural design are explored in relation to mental health treatment facilities. Earlier research suggests that patients have difficulty making the cognitive adjustment to typical mental health treatment facilities, and this can negatively effect their therapy and potential recovery. An illustrated questionnaire was developed to help determine the types of facilities patients can relate to and experience relative comfort. This questionnaire was used to examine perceptions of buildings and designs in relation to the provision of comfortable and healthy environments. The survey revealed that patients, health care providers, and students shared similar perceptions of the built environment, and that buildings possessing features generally associated with domestic buildings (houses) were considered more comfortable than other building types. In particular, buildings with pitched roofs and brick exteriors were considered most suggestive of comfort. Horizontal windows were preferred to more common vertically oriented windows. This effect was more pronounced when windows framed a pleasant natural view. Curved interior forms were also found to be suggestive of comfort. Past, current, and emerging patterns of site and facility development are reviewed in association with their environmental context. The role of nature in the healing process, from ancient Greece to recent discoveries, is also examined. The final chapter of this thesis is a demonstration of design principles with annotated drawings of a hypothetical inpatient unit and outpatient clinic. These drawings are provided to demonstrate an integration of thesis findings and design principles. These drawings are not a definitive design or prototype, because every site and building program are different and require their own design solution.
97

The Future of Energy Efficiency in Marine Corps Forward Operating Bases

Asheim, Jonathan 06 May 2016 (has links)
Sustainable Built Environments Senior Capstone Project / Marine Corps forward operating bases (FOBs) operate in austere conditions where the reliance on resupply from main bases is a necessity. A FOB in Afghanistan requires at least 300 gallons of diesel fuel a day, in which each gallon delivered requires 7 gallons of fuel to get it there by convoy. Extensive resupply convoys offer a tactical disadvantage, especially when there is one Marine casualty for every 50 convoys. Private sector innovations in energy efficiency can offer a solution to inefficient energy use and Marine casualties from IEDs – improvised explosive devices. Data analysis of private sector innovations in the fields of flexible solar, fuel cells, and atmospheric water generation, provide direction into the future of sustainable forward operating base design. Each of the proposed innovations outscore current systems by vast margins in a weighted energy efficiency scale and therefore have the potential to elevate the energy efficiency of forward operating bases. Energy efficiency, in the case of the Marine Corps, is a combat multiplier. If they are able to free themselves from the burden of their increased energy use, they gain the ability to operate more aggressively, push deeper, and fight as a lighter, more lethal force.
98

The changing role of the architect in the building process

Seddon, Robert Craig. January 1995 (has links)
published_or_final_version / Real Estate and Construction / Master / Master of Science in Construction Project Management
99

Novel evaporative cooling systems for building applications

Musa, Mu'azu January 2009 (has links)
The technology and applications of evaporative cooling to provide human comfort in buildings is not new and has been used in different places based on different methods and materials. Conventional air conditioning systems overshadowed the application of evaporative cooling for buildings despite their ozone layer depletion. Evaporative cooling using porous ceramic evaporators were experimentally investigated. Encouraging results in terms of temperature reduction and cooling effectiveness were reported. In this work also thermoelectric unit was integrated in to the evaporative cooling system containing porous ceramic evaporators. The warm inlet air cooled in the evaporative cooling chamber was passed over the hot-side fins of the thermoelectric cooling device to act as a better heat sink. Typical test results showed that the cold side temperature of thermoelectric unit was 5Deg.C lower and the hot side was 10Deg.Clower, respectively when operated on the wet and dry porous ceramics evaporative cooling chamber. Direct evaporative cooling is often associated with the rise in relative humidity which may result in uncomfortable feeling due to unwanted increase in moisture. Indirect evaporative cooling offers a solution but still requires improvements in the effectiveness. There is also need for using cheap and readily available materials for the construction, requiring simple fabrication technology without very complex engineering infrastructure. Most widely used common fibrous materials have very limited capillary effect. So a periodic water spray system with an automatic control is required for running the cooler which adds to the power consumption, rise in operation costs as well as construction and operational difficulties. As a compromise using horizontal arrangement was considered. Use of pump for supplying water required to moisten the evaporative cooling surface was eliminated. The system was constructed and tested under varying temperature, relative humidity and air flow rates. Results showed significant temperature reduction accompanied with acceptable increase in relative humidity. Temperature drop of 6-10Deg.C between the inlet and outlet temperatures of the product or supply air was recorded. Increase in relative humidity of the supply air was 6 - 10% less than the working air. Application of this novel system was demonstrated in the parasol self-cooling arrangement. The fibre tube vaporative cooler has the potential of cooling a building space to the acceptable comfort limits. The application of porous ceramics for building space cooling, integrating the system to be used as a heat sink and the use of horizontal fibre tubes for evaporative cooling are all novel ideas in this field of research. Other novel features also include the ability to minimise energy consumption by eliminating common methods of continuous water circulation.
100

An analysis of building information modelling (BIM) implementation from a planned behavior perspective

Zhang, Dan, 張丹 January 2015 (has links)
abstract / Real Estate and Construction / Doctoral / Doctor of Philosophy

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