published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

published_or_final_version / Civil Engineering / Master / Master of Science in Engineering

Indoor sources of air pollution generate a large fraction of overall human exposure to airborne pollutants. Materials used in buildings have been shown to be a major contributor to indoor air pollution, with green building agencies setting guidelines limiting their primary emissions. However, such guidelines neglect secondary emissions resulting from chemistry occurring in indoor spaces. Furthermore, limited knowledge exists regarding ozone reactions and green building materials. This study focuses on the primary aldehyde emissions, ozone deposition velocity, and secondary emissions from three green building materials: recycled carpet, sustainable ceiling tile, and low-VOC paint and primer on recycled drywall. Ozone reactions resulted in secondary aldehyde emissions ranging from no increased secondary emissions to 237 µg m-2 hr-1. Modeling results suggest that these emissions can cause concentration increases beyond odor thresholds. / text

The research is based on the European Directive aimed at harmonising standards for construction products. Harmonised standards remove technical barriers to trade allowing manufacturers to sell their products anywhere in the European Economic Area (EEA) provided the product complies with the standard and has affixed the CE marking. This should lead to greater competition in all EEA markets. A review of relevant literature covered three distinct areas; developments of the European Union and the Construction Products Directive (CPD), the UK construction industry and materials sector and strategic management concentrating on market barriers and entry strategies. The research combined these areas together by investigating the impact of the CPD on the UK construction product manufacturers specifically considering the strategic decisions of the UK brick industry. As there was little previous empirical research into this area, data was generated through exploratory interviews with manufacturers and bodies involved with the UK implementation of the Directive, through a self-completion postal questionnaire survey with manufacturers from six product groups and by a case study approach used to examine the UK brick industry. The research demonstrated that the Directive is having little impact to date on the strategic decisions of UK construction product manufacturers. Also, there are a disturbing number of producers that were not aware of the Directive and its possible implications. By applying previous research findings to the UK brick industry, conclusions were drawn highlighting the specific nature of this industry and identifying specific characteristics that influence its competitiveness. The Directive and the UK brick industry have never previously been examined in such a manner and areas for further research have been suggested.

>Magister Scientiae - MSc / Public concern about all radiation and radon exhalation from building materials has been highlighted recently. The purpose of this study is to address this public concern and to investigate the contribution of building materials to indoor radon levels. As in soil and rocks, radon gas is formed inside the building materials by decay of the parent nuclide 226Ra. It is not possible to determine the radon exhalation rate simply from the activity concentration of 226Ra, instead one must measure radon exhalation rates directly from the surface of the material. 222Rn has been identified as an important factor that could result in a health hazard by studies all around the world. The exhalation experiments were done at the UWC physics department, in the Nuclear Physics Lab. A RAD7 radon detector was used to measure the radon concentration in an air tight chamber that contained various building material samples. The RAD7 records the number of alpha particles with energy of 6.11 MeV which results from the decay of 218Po, the daughter of 222Rn. The RAD7 detector converts counts into Becquerel’s per cubic metre (Bq/m3). The building materials tested were the raw materials used in construction such as two different types of building sand, building stones, coarse aggregate, floor and roof tiles, various granites from across the world that were sourced locally and uranium bearing sandstone originating from a Beaufort-West prospecting site. Stones from this site were used as filler material in the construction of two farm houses. Most building materials were found to have a very low rate of radon exhalation. The only materials that had any significant radon exhalation were 2 granite samples with a maximum exhalation rate of 1.5 Bq.m-2.h-1 and the uranium bearing sandstone. It is safe to say that the overwhelming majority of building materials tested are safe to use but some granites may require further study. The uranium bearing sandstone is a definite radiation protection issue and should not be used in any construction.

A RESEARCH REPORT SUBMITIED TO THE FACULTY OF ARCHITECTURE. UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG, FOR THE DEGREE OF MASTER OF SCIENCE IN BUILDING / This research project is an investigation into the effect of the grading of perlite lightweight aggregates on the resultant concrete strengths. Lightweight concretes are reviewed. Perlite, as a lightweight aggregate, is assessed. Grading theory for aggregates and in particular lightweight aggregate is analysed. A series of mix designs are proposed with manipulation of the grading of the perlite as the only variable. This is so that variations in compressive strength and density may be assessed in terms of the grading of the perlite. Those mixes are undertaken and tested for compressive strength and dry density. In this research project compressive strength is considered a benefit, while mass is considered a disadvantage. The performance of a lightweight concrete is assessed firstly in terms of the Power Factor. The Power Factor is the compressive strength divided by the dry density of a concrete. The performance of lightweight concretes produced with Perlite aggregate is assessed secondly in terms of the Cement Content factor. The Cement Content Factor is the Power Factor divided by the Cement Content. This factor has the effect of creating a common denominator of the cement content. An evaluation of the results yields the conclusions detailed in chapter Eight, the principal two being: • The optimal perlite grading tested was a monodisperse, single size fraction, of between 600 and 1180 microns. • The most practical measure for manufacturers to improve the performance of lightweight / Andrew Chakane 2019

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Esta Dissertação de Mestrado trata da pesquisa e do estudo das esquadrias de alumínio para a construção civil de edifícios, nas diversas categorias de uso. Considera os aspectos referentes ao histórico do metal, aos processos de produção do alumínio e dos perfis para fabricação de esquadrias, à especificação técnica das esquadrias com suas diferentes tipologias, multiplicidade de usos e aplicações e desempenho técnico-construtivo do material. O objetivo deste trabalho é desenvolver literatura didática a respeito do sistema de vãos janelas de alumínio, de modo a orientar os profissionais da construção civil, particularmente os arquitetos, no emprego do material, aliando adequação técnica, estética e demais pormenores, além de promover a otimização de custos numa relação de custo-benefício. O produto resultante da pesquisa inserida nesta Dissertação poderá contribuir e auxiliar na elaboração do projeto e na especificação técnica das esquadrias de alumínio nos edifícios, sempre de maneira responsável e consciente. / This Masters Degree Dissertation is about the research and the study of the aluminum building products for doors and windows, considering the following aspects: the metals historic; the production process of aluminum and profiles for the windows fabrication; the technical specification of the windows, its typologies, its multiplicity of uses and applications and the performance technical constructive of the material. The objective of this job is to develop teaching literature about space systems aluminum windows, in order to orientate the professionals of civil construction, particularly the architects, to use material with the best possible way, allying technical adaptation, aesthetics, and others details, and to promote the cost optimization. The resulting of the research inside this Dissertation could contribute and helps in the technical specification, responsible and conscious, of the aluminum windows and doors for buildings.

by Ko Wing-Yee Rebecca, Ng Tat-leung George. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1987. / Bibliography: leaves 84-85.

Typescript (photocopy). / Digitized by Kansas Correctional Industries