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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

Posouzení možnosti rekonstrukce a nové výstavby mateřské školy v Blažovicích / Assessment of the Possibility of Renovation and New Construction of a Kindergarten in Blažovice

Čtvrtečková, Ludmila January 2019 (has links)
The master´s thesis deals with the determination and assessment of the complete costs of reconstruction and renovation of kindergarten in the village Blažovice, located in Brno – venkov, in the South Moravian Region. Two options were chosen to assess the complete costs. The first option contains the condition of preserving the existing building with subsequent reconstruction or modernization of the building to such an extent that the building can continue to be used for the operation of the kindergarten. The costs of reconstruction are determined using the itemized budget compiled according to the project documentation of the actual state. The second option contains the demolition and the construction of a completely new building of kindergarten. In the second option, budgets are implemented by using budget indicators combined with an itemized budget. In the end, the results of the mentioned variants are evaluated.
92

Construction and demolition waste management : assessment of demand and supply of recycled materials in the Western Cape

Delaware, Kamil January 2003 (has links)
Includes bibliographical references (leaves 96-100). / Concern for environmental degradation has been a motivating factor in the efforts to reuse or recycle construction and demolition waste. The intention is not only to reduce environmental desecration, but also to recycle the construction and demolition waste into potential building materials to be reused elsewhere. This study investigated the supply and demand of recycled construction materials in the Western Cape, and aimed to determine the perception held by important stakeholders about these materials. A qualitative analysis of the case study results revealed that poor waste management plans implemented on construction and demolition sites have affected the quality, supply and price of recycled materials. In addition to this it was also revealed that the negative perceptions regarding recycled materials were the major barriers to creating an established secondary market. Inadequate knowledge and experience were major contributors to resistance to change of perceptions. A case study was conducted on Malans Quarries Recyclers in order to determine the supply of raw materials (construction and demolition waste) reaching the recycling plant; the supply of recycled materials to the end user (consumer); and the recycling process that takes place. A sample of fifteen respondents from a variety of large, medium and small construction contractors, as well as consultants and civil engineering companies, completed a questionnaire to determine the demand for and perceptions about these materials. The qualitative analysis of the results of the questionnaires showed that the majority of respondents still preferred to use primary materials over recycled materials. However, it appears that the gap between respondents who prefer to use primary materials, and those who utilize recycled materials, has narrowed in comparison to results obtained in previous studies. It seems that there may be more usage of recycled materials in the future. The results also revealed that tax cuts, could be a good economic incentive to encourage the use of recycled material. The questionnaire results also revealed that the majority of the respondents believed that landfill taxes where not effective in discouraging the illegal dumping of waste, and that the lack advertisements, and difficulties in obtaining recycled materials played a crucial role in the under-use of recycled materials.
93

Keeping it in the loop : A roadmap to circular economy for NCC / Bibehålla i kretsloppet : En vägbeskrivning för cirkulär ekonomi i svensk byggindustri

Tabrizi, Shanar January 2016 (has links)
Resource efficiency and circular economy (CE) has become increasingly relevant to the Swedish construction company NCC in connection to the plans of demolishing the current head office in Stockholm and building a new head office next to it. NCC wants to investigate how to minimize the negative sustainability implications of bringing down a commercial facility well before its life length has expired, through exploring the possibilities of integrating principles of CE in future planning‐and construction processes. This study seeks to understand how the Swedish construction company NCC could work with decision-making for CE in order to keep their materials in the loop. As the concept of CE is broad there are many options for working with its principles. However, the construction industry is relatively new to these and a list of priorities would therefore be helpful in such an initial phase, as focusing on all would be inefficient and rather daunting. Thus, this study suggests a multi-criteria decision analysis (MCDA) as a tool for decision-making and prioritizing between various approaches to CE. Together with NCC, an MCDA was performed where three different options for working with CE were analysed (Waste as Resource, Circular Design and Circular Business Models). In a focus group, 17 criteria that were relevant to NCC were developed as a basis for analysing the options. These were then defined, scored and weighted to reveal a most preferable option. The MCDA showed that the most preferable approach to CE for NCC is working with circular design, i.e. Design for Deconstruction (DfD), followed closely by measures to increase the rate of reuse and recycling of already existing construction- and demolition waste. However, the sensitivity analysis revealed that if economic criteria received a higher weight, increased reuse and recycling is the most preferable option. MCDA was deemed a helpful decision-making tool for CE principles. While the scoring and weighting is subjective and it is challenging to quantify the criteria, the strength lies in bringing a new and innovative topic on the agenda by gathering key decision-makers in focus groups to discuss and learn. A preliminary study to this thesis was conducted at NCC (Tabrizi, 2015) with the aim of conducting a survey of good examples with regard to development of commercial properties that are designed for flexibility and deconstruction during refurbishment and end‐of‐life. It showed that the challenges relate to the hesitant perception of secondary material, design and construction limitations, the need for material documentation, organization and logistics as well as creating sustainable business models. Key success factors for overcoming these challenges for NCC is working towards better communication and promotion of secondary material through information sharing, building up a knowledge base and internal targets, as well as establishing a consistent work methodology for DfD in order to move NCC towards a circular economy.
94

En studie av möjligheter och hinder att återanvända rivningsavfall i Gästrikeregionen / Reuse of demolition waste in the Region of Gävleborg, Sweden

Birgersson, Hugo January 2020 (has links)
Increased effectivity in resource management in the construction sector is required to achieve the environment goals of Agenda 2030. The largest source of total accumulated waste derives from the construction and demolition area. This thesis contains a literature study about circular economy application in the process of construction- and demolition waste and interviews with local actors that represent the Swedish construction material chain in the Region of Gästrike, Sweden. A cooperation with the municipality property owner Gavlefastigheter AB has provided an opportunity to study the demolition process to examine what actions the building sector requires to increase reusage of demolition waste. Gavlefastigheter AB own and manage a variation of building types such as schools, agencies, sports arenas and other exclusive designs. The result of this study shows that the existing policy instruments of waste management are primarily developed to evaluate climate change impacts and to avoid waste that could cause harm to the environmental and health. In the literature review life cycle assessment was shown to be the most common method to analyze the effects of circular economy. The Swedish construction Federation have recently updated the construction- and demolish waste management directives mainly to help transitioning the construction business towards circular economy. Albeit these directives are not yet practically utilized the result of the interviews of local actors indicated that there were a few practices of demolish with reusage applications. The conclusion summarizes the important subjects that need to be dealt with to increase reusage within future demolition projects in the Region of Gästrike, Sweden.
95

Hodnota stavebního pozemku zastavěného stavbami určenými k demolici / The Value of the Building Land Which is Settled by Buildings That Are Determined for Demolition

Řádek, Lukáš January 2012 (has links)
This engineering thesis deals with quantification of the value of a development land built buildings that are destined to be demolished. This thesis outlines the aspects of demolition procedures with subsequent usage of the building rubble for recyclation. The goal of this thesis is to illustrate issues of demolitions of bulindings situated on a development land and of determinativ of the total price of such land.
96

Information Flow in Reuse Prospects of Construction Materials : Analysis of information flow in the Swedish construction industry

Chandran, Rahul, Joseph, Neha January 2023 (has links)
Efficient management of construction and demolition components is crucial for the sustainability of the environment, society, and economy. Reusing construction materials is an effective way to reduce construction debris. However, reuse is hurdled due to different factors, and one of the leading causes of these factors is improper information flow. The information flow is the transfer of relevant information within the network about construction materials such as quality, quantity and other specifications in the reuse aspect. The seamless flow of relevant information on the construction process and materials is crucial to facilitate reuse. Unfortunately, there are considerable obstacles to achieving a seamless information flow. By identifying and addressing the barriers that hinder the current information flow, we can thrive towards a seamless flow of information that facilitates reuse within the construction industry. This paper examines the challenges in the flow of information within the Swedish construction industry using a qualitative exploratory research design. The research also explores some strategies adopted by a few stakeholders to promote reuse. The study is performed using existing literature and interviews with various stakeholders mainly in the Swedish construction industry. The research identifies several barriers in information flow, including a lack of collaboration among stakeholders, fragmented information, no standardization, business models that do not support reuse, and low awareness of reuse prospects. To gain better insight into the flow of information, a five-component framework has been devised based on these challenges.
97

Construction And Demolition Debris Recovery And Recycling In Orange County, Fl

Toth, Michael Stephen, II 01 January 2012 (has links)
In 2008, the State of Florida established a recycling goal of 75% to be achieved by 2020. In response to the Florida goal Orange County (OC), Florida has made the development and implementation of an efficient strategy for landfill diversion of its solid waste a top priority. The Florida Department of Environmental Protection (FDEP) estimated that 23 % of municipal solid waste was generated by construction and demolition (C&D) activities in 2009, with only 30 percent of C&D debris being recycled. Therefore, OC decided to create a solid waste integrated resource plan (SWIRP) initially focused on the recovery and recycling of C&D materials (2010). For SWIRP development, OC decision makers need the best available data regarding C&D debris generation and composition and an understanding of the potential markets available for recycled materials. In this investigation debris generation was estimated over the period of 2001 to 2009 for the largest single governing body within OC, unincorporated OC (UOC), representing 65 percent of county population. The debris generation model was constructed for years 2001-2010 using area values for C&D activities in six sectors obtained from building permits and debris generation multipliers obtained from literature values. The benefit of the model is that as building permit information is received, debris generation estimations can also be expediently updated. Material composition fractions obtained from waste characterization studies of landfills in the Central Florida area were applied to the debris generation model resulting in a material iv composition for all sectors for years 2001-2010. The material composition of the debris stream was found to be, on average, concrete (53%) drywall (20%), wood (12%), a miscellaneous fraction (8%), asphalt roofing material (4%), metal (2%), cardboard (1%) and carpet and padding (1%). A market analysis was performed for concrete, drywall, wood, asphalt roofing shingles and residual screened materials (RSM). It was found that statewide, markets existed for 100 percent of the materials studied and could replace significant amounts of natural material feedstocks, but that the development of more local markets was vital to meeting OC’s diversion goal to minimize the cost of transporting recyclables.
98

Development of Alkali-Activated Binders froRecycled Mixed Masonry-originated Waste

Yildirim, Gurkan, Kul, A., Özçelikci, E., Sahmaran, M., Aldemir, A., Figueira, D., Ashour, Ashraf 24 July 2020 (has links)
Yes / In this study, the main emphasis is placed on the development and characterization of alkali-activated binders completely produced by the use of mixed construction and demolition waste (CDW)-based masonry units as aluminosilicate precursors. Combined usage of precursors was aimed to better simulate the real-life cases since in the incident of construction and demolition, these wastes are anticipated to be generated collectively. As different masonry units, red clay brick (RCB), hollow brick (HB) and roof tile (RT) were used in binary combinations by 75-25%, 50-50% and 25-75% of the total weight of the binder. Mixtures were produced with different curing temperature/periods and molarities of NaOH solution as the alkaline activator. Characterization was made by the compressive strength measurements supported by microstructural investigations which included the analyses of X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX). Results clearly showed that completely CDW-based masonry units can be effectively used collectively in producing alkali-activated binders having up to 80 MPa compressive strength provided that the mixture design parameters are optimized. Among different precursors utilized, HB seems to contribute more to the compressive strength. Irrespective of their composition, main reaction products of alkali-activated binders from CDW-based masonry units are sodium aluminosilicate hydrate (N-A-S-H) gels containing different zeolitic polytypes with structure ranging from amorphous to polycrystalline.
99

Properties of geopolymers sourced from construction and demolition waste: A review

Alhawat, Musab M., Ashour, Ashraf, Yildirim, Gurkan, Sahmaran, M. 13 April 2022 (has links)
Yes / Geopolymers have been recognised as a viable replacement to ordinary Portland cement (OPC), providing a cleaner solution since it can significantly reduce greenhouse gas emissions as well as accomplishing effective waste recycling. Construction and demolition waste (CDW) has been recently identified as raw materials for geopolymers due to its availability and high contents of silica and alumina. This paper aimed at reviewing the current state-of-the-art on the geopolymer paste, mortar, and concrete production and their properties, with special attention paid to geopolymers incorporating CDWs. The review covers brief assessment of using CDWs in concrete, the mix design of geopolymer mixtures in addition to identification of the main factors influencing the performance of geopolymer containing CDW. The most recent data related to the mechanical and durability properties of CDW-based geopolymers are presented, while the cost and environmental impacts of using recycled materials in producing geopolymer concretes are also discussed. Geopolymer concretes have a vast range of possible applications, however, there are still several barriers facing commercialisation of geopolymers in construction industry. The review indicated that it is possible to produce geopolymer concretes from CDW-based materials with properties comparable to OPC-based ones; however, the selection of proper material composition should be carefully considered, especially under normal curing conditions.
100

A comprehensive study on the compressive strength, durability-related parameters and microstructure of geopolymer mortars based on mixed construction and demolition waste

Ozcelikci, E., Kul, A., Gunal, M.F., Ozel, B.F., Yildirim, Gurkan, Ashour, Ashraf, Sahmaran, M. 20 February 2023 (has links)
Yes / As a viable option to upcycle construction and demolition waste (CDW) into value-added materials, geopolymer technology is emerging. Most studies investigate CDWs in a separated form or in combination with mainstream pozzolanic/cementitious materials focusing only on fundamental properties of geopolymer pastes, not considering to scale such materials to the level of their application in the forms of structural mortars/concretes or to characterize long-term performance/durability. This study investigated the development and characterization of ambient-cured mortars with mixed CDW-based geopolymer binders and untreated fine recycled concrete aggregates (FRCA). Mixture of CDW-based roof tile (RT), red clay brick (RCB), hollow brick (HB), concrete (C), and glass (G) was used as the precursor, while ground granulated blast furnace slag (S) was used in some mixtures to partly replace CDW precursors. Compressive strength, durability-related parameters including drying shrinkage, water absorption, and efflorescence, microstructure and materials sustainability were evaluated. Results showed that 28 d compressive strength results above 30 and 50 MPa is achievable with the entirely CDW-based and slag-substituted mortars, which were found improvable to have entirely CDW-based structural concretes. Drying shrinkage of the mortars is slightly higher than that of conventional cementitious/geopolymeric systems although it can be minimized significantly through mixture optimization. Water absorption values remain comparable with the literature. CDW-based geopolymer mortars outperform Portland cement mortars in terms of CO2 emission and energy requirement. Our findings show that via utilizing CDW-based constituents in mixed form as precursor and waste aggregates, it is possible to develop greener construction materials with acceptable strength and long-term performance. / This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 894100. The authors also wish to acknowledge the support of the Scientific and Technical Research Council (TUBITAK) of Turkey provided under project: 117M447.

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