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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.
21

Miljöbyggnad, GULD värt? : En undersökning av fastighetsägares erfarenheter och tankar kring ett nytt certifieringssystem / Miljöbyggnad, a value of GOLD?

Berggren, Jonathan January 2014 (has links)
During the past few years an increased attention has been paid to environmental issues in the construction and property sector in Sweden. In order to simplify the work with these issues a Swedish environmental certification system for buildings called Miljöbyggnad has been developed. This thesis aims to investigate the opinion of a selected number of selected property owners of Miljöbyggnad. From that basis recommendations and actions for the future work with the system will be presented. The investigation has been conducted through personal interviews with five property owners. The main issues that the interviews have been based on are their purpose, experiences, perceived complications and future prospects in terms of certification using Miljöbyggnad. The system intends to be cost-effective, simple and to offer a relevant environmental assessment of buildings and the result from the report indicates that this is largely fulfilled. All respondents believe that Miljöbyggnad offers a relevant environmental assessment. All of them also believe that the system is simple except for some complications and 80 % believe that the system is cost-effective. In terms of the future, all interviewed property owners will most likely certify buildings under Miljöbyggnad, some to a greater extent than others. The conclusion from this investigation is that the system needs to be dynamic. Adaption to the social, environmental, technical, economical and legal conditions that prevail is vital. However, it is recommended that Miljöbyggnad retains its simplicity and avoid growing to become too comprehensive.
22

Sustainable utilisation of raw sewage sludge (RSS) as a water replacement in cement-based materials containing unprocessed fly ash

Hamood, Alaa January 2014 (has links)
Prior to the implementation of the European Union Urban Waste Water Treatment Directive (91/271/EEC) in 31 Dec 1998, around a quarter of the sewage sludge produced in the UK was either discharged to surface waters via pipes or disposed from ships at sea. Discontinuing this route together with the quality requirements of the European Waste Water Directive, led to the generation of significant quantities of sewage sludge. It has therefore become required to treat this waste effectively before it can be sent back to the environment. Consequently, this added greater challenges for the environmental agencies, as well as local authorities. The treatment process comprises costly and energy consuming applications including physical, chemical, biological and thermal. In addition to the sewage sludge, the power generation industry produces massive quantities of fly ash from burning coal. In the UK, there is about 5,300,000 tonnes of fly ash that are generated annually, which require to be processed and classified in order to meet the standard requirements before it can be used in the construction applications. The classifying process also involves a series of costly and energy consuming mechanical and physical applications. This research programme has introduced an innovative alternative to the traditional re-use and disposal routes of Raw Sewage Sludge (RSS) and unprocessed fly ash. It has suggested the utilisation of RSS and unprocessed fly ash as raw ingredients for the production of sustainable construction materials. This research programme has therefore examined the performance of cement-based materials containing Raw Sewage Sludge (RSS) as a water replacement and unprocessed fly ash as cement replacement. Mortar and concrete mixes incorporating these materials were tested for their flowability/workability, density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series 1), mortar mixes with RSS and large proportions of unprocessed fly ash (Series 2), and concrete mixes with RSS and unprocessed fly ash (Series 3). The outcomes of the investigation were encouraging in that cement-based materials containing RSS and unprocessed fly ash that were produced demonstrated relatively good engineering, durability and environmental properties in comparison to the control mixes. The inclusion of unprocessed fly ash significantly reduced flowability/workability; however it improved long-term compressive strength for both mixes with RSS and water. The best compressive strength results were recorded when cement was replaced with 10-20% unprocessed fly ash by weight of total binder. The results also showed that sulphate attack resistance improved when fly ash was included. Moreover, safe concentration levels of heavy metals and free ions were detected when leaching test was performed. However, it must be kept in mind that more environmental tests must be performed before any large scale use is undertaken.
23

A study on green building solutions in Botswana 2014

Malan, Heinrich 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: This research assignment was done to determine the status and awareness of green building solutions in Gaborone, Botswana for the year 2014. In a third world country like Botswana, design and development of ‘green building’ is low on the agenda. As with many other third world countries, other basic needs and services are missing and many people believe that all of those should be sorted out before items such as green building solutions can be looked at. Interviews were conducted with executives of companies in the property development industry or companies that make use of commercial office space. Through these executives, access was gained to the employees who were requested to complete an online survey. The focus of the interviews and surveys was to gain information of the companies’ awareness of and involvement in green building solutions, their view on the willingness to pay for such solutions and on its implementation in the future. In the findings, it became clear that cost is the most important aspect, especially when renting, while when investing, most participants were willing to contribute towards green building solutions with the understanding that this would contribute to lower running costs, and therefore returns on the investment made.
24

An integrated approach to value management and sustainable construction during strategic briefing in Saudi construction projects

Al-Yami, Ali M. H. January 2008 (has links)
There has recently been considerable concern regarding the degradation of the environment caused by depletion of natural resources, air pollution, global warming and the lack of consideration paid to the earth's ecosystem. The principles of sustainable construction are thus being widely adopted by many countries all over the world. This quest towards sustainable development throughout the world has put a spotlight on the construction industry. Sustainable construction is a major concept underlying a variety of efforts to ensure a good quality of life for the present and future generations. Most developing countries have experienced a fast uptake of urbanisation and the acceleration of infrastructure development, all of which fuel the necessity of establishing sustainable construction principles; this is true in Saudi Arabia as in other countries. This research has carefully investigated the current situation of Value Management (VM) and Sustainable Construction (SC) in the Saudi construction industry in terms of their application, clients' attitudes, barriers to implementation, identification of enablers that could overcome these barriers and improve their implementation, and determination of the level of existent knowledge about both subjects among people who work in the Saudi public sector. It has also defined Sustainable Construction principles in three dimensions, in Saudi Arabia: environmental, economic and social. The research findings have revealed that SC principles are not a major consideration in the Saudi construction industry and many people who work in the Saudi public sector have little or no experience in sustainable development. On the contrary, VM has been applied in the Saudi construction industry for more than three decades and its application is mandatory in all governmental projects funded by the Saudi government. This enables those people who work in the VM sector to possess great experience, skills and knowledge. However, there are a number of barriers that could impede or affect the VM performance in the Saudi construction industry which were taken into account in this research. (Continues...).
25

Risk Management in Sustainable Projects in the Construction Industry : Cases of Swedish Companies

Apine, Anete, Escobar Valdés, Francisco José January 2017 (has links)
Sustainable construction projects are expanding in the market and green codes andstandards are advancing giving the ground for development of technology and materialsapplied. With every new material and technology utilised in the field, also risks aregrowing. The importance of risk management in sustainable construction projects isthus increasing and more experience and expertise is needed. So, the purpose of thisthesis is to examine and gain deeper understanding of project related risks in sustainableconstruction projects in Swedish companies operating in built environment. It is crucialto gain knowledge of good practices within the industry to be able to propose furtherinvestigation of the subject that could improve the existing risk management andsustainable construction project goals.This thesis examines the existing theory of the risk management process and sustainableprojects by shedding light on the trends within the construction industry. The intentionof the thesis is to add value to the existing gap in the theory that suggests thatconstruction industry is exposed to more risks and uncertainty than perhaps otherindustries, and that introducing sustainability adds more uncertainties and risks. Thisphenomenon is claimed to be due to the lack of knowledge and experience in the areaand, thus, practitioners seek for new ways how to tackle the arising issues. This thesisattempts to display how Swedish companies who are working with green and highperformance buildings identify and deal with risks.Two Swedish companies operating in built environment were chosen in order toinvestigate different ways of dealing with risks and the trend of sustainability inconstruction. Those in charge of risk and sustainability within the companies wereinterviewed applying semi-structured interviews and additional information wasgathered through multiple sources, such as annual reports, web pages and otherdocuments. This thesis has exploratory and qualitative research design and appliesabductive approach for the purpose and the nature of phenomena.The findings showed the different tools how risk management is applied in thecompanies and how it is related to the risks faced in green building construction. Theresults showed the importance of tools applied tackling sustainable construction projectsthat companies have applied and added to their processes in order to manageuncertainties that could occur if these processes were not implemented. As regards thegeneralisability towards findings, there still could be added more companies and futureresearch could imply also maturity of the companies to make findings more precise.However, after consideration of the processes learnt from companies, the proposedmodel for achievement of successful sustainable construction projects can be followedand applied in other companies operating in this industry.
26

LIFE CYCLE COST ANALYSIS OF AN ENERGY EFFICIENT RESIDENTIAL UNIT

Ayushi Hajare (6632219) 14 May 2019 (has links)
<div> <p>The residential building sector is one of the most energy intensive sectors in today’s civilization. With population growth and a rise in number of homeowners the effect is bound to worsen. A wave of green and sustainable strategies is on the rise hoping to moderate some of the negative effect on the environment. From embracing renewable sources of energy as an alternative to fossil fuels, to improving existing home systems to become more efficient, the construction industry is evolving into becoming more energy conscious. One of the biggest obstacles to this wave is a lack of awareness and a fear of initial costs among contractors, homeowners and clients alike. This research will use Life Cycle Cost Analysis on a varying combination of residential energy systems and the researcher hopes to establish the trade-off between initial investment and long-term benefits. The case being considered is a residence located in Indiana, US. Using past and current utility bills and energy simulation data of different energy consuming systems in the residence over its lifetime, economic models are generated. This research establishes that a combination of passive and active energy conservation measures results in the lowest life cycle cost. The study will be beneficial for further research and as a framework for residential life cycle cost analysis.</p></div>
27

Developing a self-sustaining secondary construction materials market in South Africa

Macozoma, Dennis Skhumbuzo 11 March 2008 (has links)
ABSTRACT Sustainable development has become part of Government policy across the world. In the construction industry it has been introduced through the promotion of “sustainable construction” or “green construction”. International trends show a gradual move away from wasteful construction industry practices that include high resource consumption, material wastage, inefficiencies in construction processes and a high percentage of waste that find its way to waste disposal sites and illegal dumps. This research report seeks to promote sustainable construction and waste minimisation as preferred models for achieving a balance in the economic, social and environmental impacts of development. It reviews South Africa’s construction and demolition site practice from the perspective of construction and demolition waste management, assessing waste management practice and the resultant waste disposal. To gauge South Africa’s performance it benchmarks South African practice against those of the United States, United Kingdom, Germany and the Netherlands. This approach highlights gaps in South Africa’s current practice and also provides some valuable lessons that can be used to ensure compliance with sustainable construction principles. Finally the research report proposes a framework for developing a self-sustaining secondary construction materials market in South Africa, which can prove to be a valuable tool for ensuring the absorption of sustainable construction in the construction industry.
28

Durability prediction of recycled aggregate concrete under accelerated aging and environmental exposure

Unknown Date (has links)
This study is to compare the performance of recycled aggregate concrete and the impact of up to 50% cement replacement with fly ash on durability. Water content, sieve analysis, standard and modified compaction tests were performed to assess the physical properties of the recycled aggregate concrete. Accelerated aging tests were performed to predict the long term durability of the recycled aggregate concrete. Following Arrhenius modeling and TTS and SIM accelerated aging protocols, a time versus stiffness master curve was created. This allowed the prediction of equivalent age using experimental data and theoretical analysis. To account for environmental exposure, the specimens underwent 24 and 48 hours of wet-dry cycling and subjected. Overall there was an increase in stiffness and strength from the specimens containing fly ash. All tests performed predicted equivalent age beyond the testing period of 144 hrs. and up to 7 years. Specimens containing fly maintained a constant and higher density to environmental exposure. / by Lillian Gonzalez. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
29

Bulk diffusion of high performance concrete specimens exposed to different levels of sodium chloride and seawater

Unknown Date (has links)
The purpose of this study was to investigate the performance to chloride penetration of specimens made with three base compositions (three different supplementary cementitious materials) and water to cementitious ratios of 0.35, 0.41, or 0.47. The specimens were subjected to bulk diffusion test or full immersion. The mixes were exposed to 0.1 M, 0.6 M, or 2.8 M sodium chloride solution for different periods of time. Also, partially immersed specimens were exposed to indoor and outdoor exposures (tidal, splash, barge). Chloride concentration profiles were obtained and the apparent diffusion coefficient was calculated. The skin effect was found only on some chloride profiles exposed to 0.1 M sodium chloride solution. The chloride binding capacity was calculated; specimens with 20% Fly Ash and 8% Silica Fume had the highest binding capacity (70.99%). The apparent diffusivity coefficient was found to be dependent on the curing regime as well as the water to cement ratio. The correlation between effective resistivity and apparent diffusion coefficient was determined. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
30

Poluição atmosférica por emissão de material particulado: avaliação e controle nos canteiros de obras de edifícios. / Particulate matter air pollution: evaluation and control on buildings construction sites.

Resende, Fernando 14 June 2007 (has links)
Os canteiros de obras são causadores de diversos impactos ambientais relacionados ao grande consumo de recursos e à grande geração de poluição e incômodos que afetam toda sociedade. Dentre as fontes de poluição, está a emissão de material particulado na atmosfera, responsável por uma série de problemas respiratórios e cardíacos, danos à flora e à fauna, incômodos à vizinhança, danos ao solo, à água e à qualidade do ar, entre outros aspectos. Em vários países, os canteiros de obras são reconhecidos como uma das principais fontes de poluição por partículas. O objetivo deste trabalho é identificar as principais fontes emissoras de material particulado entre as diversas atividades de construção, as principais ferramentas de controle e prevenção de emissão e os principais métodos de monitoramento aplicáveis aos canteiros de obras de edifícios. Sua metodologia está baseada em compilação e análise de bibliografia nacional e internacional disponível.Como resultados, são identificadas as principais fontes de emissão de material particulado nas fases de demolição, movimentação de terra e serviços preliminares e serviços de construção. Mostra-se, também, que o monitoramento, associado a ações de prevenção e controle, é uma ferramenta eficaz para manutenção de níveis de emissão aceitáveis, utilizando equipamentos de custo relativamente baixo, fácil operação e implantação no canteiro de obras. Finalmente, o trabalho traz um conjunto de recomendações que podem ser utilizadas na composição de um plano de gestão para prevenção, controle e monitoramento de emissões de material particulado em canteiros de obras, a ser incorporado às práticas de gestão já em uso pela empresa construtora. O trabalho conclui que o controle de emissões nos canteiros de obras de edifícios pode ser aplicado por empresas construtoras, dentro da atual realidade brasileira. / The construction sites cause many environmental impacts related to high consumption of resources and high levels of pollutions emissions, affecting the whole society. Among these pollutions, it is the particulate matter emission in the atmosphere, responsible for heart and lung diseases, damages to animals, plants, soil, water and air quality and nuisances to neighbors. In several countries, the construction sites are recognized as one of the main sources of particle pollution. This work intends to identify the main emission sources of particulate matter among the great variety of construction activities, the main particle emissions control tools and the main monitoring methods available for building construction sites. The research is based on compilation of Brazilian and international bibliographies. As result, are identified the main sources of particulate matter emission on demolition, earthmoving and construction activities. The work presents that monitoring associated with prevention e control measures is an effective tool for maintenance of controlled emissions levels, through low cost, easy operation and easy implantation equipments. Finally, the work presents a set of recommendation to elaborate a management plan to prevent, control and monitoring particulate matters emissions in the construction sites, easily adapted to the current management practices of the contractors firms. The work concludes that the particulate matter emission control can be implanted by contractors firm within the current Brazilian reality.

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