Faculty of Engineering and the Built Environment (Research Outputs)

Permanent URI for this communityhttps://hdl.handle.net/10539/38045

Browse

Filters

Settings

Has files: Yes

Search Results

Now showing 1 - 10 of 27
  • Thumbnail Image
    Item
    Balancing urban regeneration to prevent displacement: a conceptual strategy for inclusivity in South Africa
    (Proceedings of the AfRES 2024 Conference, 2024-09) Gethe, Faranani; Simbanegavi, Prisca
    The regeneration of urban areas and neighbourhoods plays a crucial role in mitigating urban decay and enhancing socio-economic conditions. However, conventional urban renewal initiatives often inadvertently perpetuate geographies of exclusion, chiefly through gentrification and displacement. This paper is aimed at devising effective urban regeneration strategies that prioritise social inclusivity while mitigating the negative impacts of gentrification and displacement of poor people. The study employed a literature and theoretical review approach, utilising published articles and documents to assess the impact of urban regeneration programs on poor communities. The outcomes include the identification of shortcomings in current urban regeneration strategies and the need to formulate more equitable approaches. This study's significance lies in its contribution to expanding knowledge on urban redevelopment, particularly in the developing world of the global south. Furthermore, it will inform policy development aligned with Sustainable Development Goal 11 (Sustainable Cities and Communities) of the United Nations, thus facilitating much-needed advancements in urban development policies.
  • Thumbnail Image
    Item
    Comparing occupant satisfaction in Green versus Conventional Residential Real Estate in South Africa
    (Proceedings of the AfRES 2024 Conference, 2024-09) Masotya, Adam; Simbanegavi, Prisca; Weaich, Malcolm; Adewunmi, Yewande; Ndlovu, Pride; Gethe, Faranani
    This study compares occupant satisfaction in green versus conventional residential real estate in South Africa. It investigates the benefits and satisfaction levels related to green developments, particularly in terms of energy savings and socio-economic Impacts. The research aimed to determine if there is a significant difference in occupant satisfaction between green and conventional residential developments. A quantitative approach was employed, utilizing stratified random sampling to survey 160 occupants from two developments: Crossberry Central (green) and Little Manhattan (conventional). Data was analysed using the Mann-Whitney U and Wilcoxon W tests due to non- normal data distribution. The findings indicate that occupants of green developments report significantly higher satisfaction levels. Key areas of satisfaction include air quality, utility savings, and environmental benefits. Green developments demonstrate higher levels of satisfaction regarding reduced utility bills, improved indoor air quality, and contributions to environmental conservation. The study concludes that green residential developments significantly enhance occupant satisfaction compared to conventional housing. This suggests a socio-cultural shift towards valuing sustainable living environments, emphasising the importance of promoting green building practices to improve both environmental and occupant well-being.
  • Thumbnail Image
    Item
    Phase proportions, carbon equivalent, mechanical properties and their effect on material cost of railway axle steels
    (Springer, 2018-04) Klenam, D.E.P.; Chown, L.H.; Papo, M.J.; Cornish, L.A.
    Commuter trains with solid axle configuration are produced from medium carbon steel due to cost restrictions. High-speed trains have hollow axle configuration for reduced weight and are made from high strength low-alloy (HSLA) steels. The HSLA steels have higher amounts of C, Cr, Ni, Mo, V and Nb, and are more expensive than medium carbon steels. The effects of phase proportions, carbon equivalent (CE), yield strength and ultimate tensile strength (UTS) on material costs of existing railway axle steels were studied using Thermo-Calc. Medium carbon rail axle steels had higher Fe3C phase proportions than the HSLA steel rail axle grades. Higher affinity of Cr, Mo and V for C than Fe resulted in decreased cementite proportions. The HSLA steels had yield strengths above 370 MPa, and UTS above 750 MPa, with increased material cost above $3300 per ton. A scattered distribution was observed for the pearlite weight fraction and material costs, with most between $3200 and $3400. The yield and tensile strengths increased with increasing carbon equivalent and pearlite weight fraction. The data aided the selection and design of alloys with better mechanical and corrosion properties at reduced material cost.
  • Thumbnail Image
    Item
    In vitro Evaluation of Porous borosilicate, borophosphate and phosphate Bioactive Glasses Scaffolds fabricated using Foaming Agent for Bone Regeneration
    (Nature Research, 2018) Erasmus, E. P.; Sule, R.; Johnson, O. T.; Massera, J.; Sigalas, I.
    In this work, glasses within the borosilicate borophosphate and phosphate family were sintered into 3D porous scaffolds using 60 and 70 vol. % NH4(HCO3) as a foaming agent. All scaffolds produced remained amorphous; apart from one third of the glasses which crystallized. All produced scaffolds had porosity >50% and interconnected pores in the range of 250–570 μm; as evidenced by μCT. The in-vitro dissolution of the scaffolds in SBF and changes in compression were assessed as a function of immersion time. The pH of the solution containing the borosilicate scaffolds increased due to the typical noncongruent dissolution of this glass family. Borophosphate and phosphate scaffolds induced a decrease in pH upon dissolution attributed to the congruent dissolution of those materials and the large release of phosphate within the media. As prepared, scaffolds showed compressive strength of 1.29 ± 0.21, 1.56 ± 0.63, 3.63 ± 0.69 MPa for the borosilicate, borophosphate and phosphate samples sintered with 60 vol. % NH4 (HCO3), respectively. Evidence of hydroxyapatite precipitation on the borosilicate glass scaffolds was shown by SEM/EDS, XRD and ICP-OES analysis. The borophosphate scaffolds remained stable upon dissolution. The phosphate scaffolds were fully crystallized, leading to very large release of phosphate in the media.
  • Thumbnail Image
    Item
    An evaluation of the quantitative risk assessment simulation undertaken during the planning stage of mega-projects
    (University of the Witwatersrand, Johannesburg, 2024-07) Zwane, Sibongile; Schutte, David; Maila, Sue; Jones, Razaak; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    This research examines how the absence of robust risk identification processes during the planning stage can significantly impact the quantitative risk assessment (QRA) outcomes and increase the likelihood of cost overruns in mega-projects in South Africa. By analysing specific mega-projects and their risk identification procedures, this study highlights the importance of a high-quality assessment of the QRA input stage in the context of these mega-projects. Through surveys and interviews with project managers and stakeholders, the study has provided deeper insights into the consequences of inadequate planning, such as project cost overruns and decreased project profitability. The research indicated that a robust risk identification process during the planning stage is pivotal in mitigating cost overruns in mega-projects in South Africa. Projects that prioritise structured methodologies involving all the relevant stakeholders and conduct comprehensive risk identification practices are better equipped to control project costs. The unanimous agreement on the significance of risk identification in cost overrun prevention emphasises its paramount importance. The findings will contribute to the risk management body of knowledge, offering valuable recommendations for improved risk identification and mitigation strategies to enhance project outcomes and positively impact project owners. Lastly, the paper sheds light on the nuanced landscape of risk identification, its impact on cost overruns, and the strategies for its improvement.
  • Thumbnail Image
    Item
    Detecting and preventing unbalanced bidding in South African public sector construction
    (University of the Witwatersrand, Johannesburg, 2024-07) Tilese, Neliswa; Makhaga, Thendo; Mphahlele, Matjelele; Zungu, Zamageda; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    Unbalanced bidding in public sector infrastructure projects is a key challenge, involving the manipulation of unit prices without adjusting the overall bid. Unbalanced bidding increases the client’s financial risks and the likelihood of project abandonment by the contractor. Existing literature provides guidelines for detecting and preventing bid price imbalances but inadequately addresses the practical implementation and efficacy of these approaches. This research aims to evaluate the practices for detecting and preventing unbalanced bidding in the South African public sector against existing formal models. This qualitative case study employs semi-structured interviews with quantity surveyors from public sector clients in Gauteng, South Africa. The purposive, non-probabilistic sampling targets professionals with relevant expertise. A thematic analysis of the interview data reveals insights into the awareness, consequences, and practices associated with unbalanced bidding in the South African public sector. The study findings highlight the need for strengthened governance and accountability, more robust strategies for detection of unbalanced bidding, and enhanced education of practitioners to promote fair competition and ethical practices in awarding projects.
  • Thumbnail Image
    Item
    The job satisfaction of black female quantity surveyors
    (University of the Witwatersrand, Johannesburg, 2024-07) Punungwe, Fungai; Terblanche, Rolien; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    Black women face discrimination in the quantity surveying profession hence experiencing tension to balance their careers and life, which results in them not being satisfied with their jobs. The aim of this research is to assess the job satisfaction of black females in quantity surveying and examine if discrimination affects it. Data was collected through online interviews with Black females that are Quantity Surveyors. The results were analysed using thematic analysis to assess similarities in responses. Issues of harassment discrimination were significantly recognised through deep interviews with participants. The issue of job satisfaction of black female quantity surveyors is less explored in literature. The findings of this research can be used by bodies of knowledge and industry professional to improve measures on issues of inequality and alleviate any problems.
  • Thumbnail Image
    Item
    Key barriers to green building implementation in South Africa
    (University of the Witwatersrand, Johannesburg, 2024-07) Mompati, Lerato; Mandlate, Mike; Kabini, Karabo; Nomvalo, Usiphe; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    Due to climate change, South Africa is faced with economic and health challenges. Adopting green building technologies reduces the amount of energy usage, however the implementation of green building in South Africa has been slow. This research aimed to identify the barriers on the implementation of green building and the methods that can be adopted to enhance the growth of green building in South Africa. A qualitative research method was be adopted. The open-ended interviews were conducted with built environment professionals. The main barriers of green building implementation are: initial high cost, lack of awareness, lack of incentives, and resistance to change. Recommendations to enhance the growth of green building practices in South Africa include: updating building codes, expanding training programs, fostering collaboration between the public and private sectors, offering financial incentives, promoting the re-purposing of existing structures, and using performance-based contracts. The paper has highlighted the key barriers of green building implementation in South Africa and developed a database of the relevant studies which can further guide future researchers, stakeholders and policymakers in this area.
  • Thumbnail Image
    Item
    Evaluating the new universities project outcomes using the PMBOK project performance domains
    (University of the Witwatersrand, Johannesburg, 2024-07) Mosalaesi, Tsholofelo; Laryea, Samuel; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    The Project Management Institute (2021) PMBOK Guide seventh edition presents eight essential domains or activities that are crucial to ensure the success of a project. PMI (2021) defines these Project Performance Domains as a group of related activities that are critical for the effective delivery of project outcomes. The PMI’s new focus on performance and project outcomes marks a significant shift away from traditional project management tools and techniques. This paper uses the eight PPDs as a framework to determine the critical factors that enabled the success of the new universities project based on the eight domains. A completed project with comprehensive data was used for the analysis. Hence, data from the project close out report was analysed using the thematic analysis method to identify the key project performance practices that were formulated and implemented to successfully achieve the intended outcomes. The key success factors identified relate to the role of the client as a leader, stakeholder’s productive working relationship and the delivery of the project within 1% of the control budget. There may be a common assumption that all clients may employ project managers who may possess the skills to execute these critical functions successfully. However, this is not always the case on all projects, and there is also varying degrees of competency among project managers. Therefore, clients should ensure that those playing leadership roles in their projects are well equipped to perform these critical functions successfully as a condition to achieve better infrastructure project outcomes.
  • Thumbnail Image
    Item
    Barriers to digitalization of procurement – a review
    (University of the Witwatersrand, Johannesburg, 2024-07) Ojo-Fafore, Elizabeth; Laryea, Samuel; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    The concept of digital technology is making waves in the construction industry in developed countries; however, it is not the same story in other nations as there are several barriers militating the progress of adoption of the new concept. This study aims to investigate the barriers militating digitalization of procurement in Construction, to proffer solutions. This study investigated possible barriers affecting the implementation of digitalization of procurement using a descriptive literature review. Several past works were reviewed to fill the gaps and apply new methods that will enable the digitalization of procurement. The study discovered several barriers restraining the digitalization of Procurement, but there are three common barriers to the literature reviewed; insecurity, cost, and Lack of skilled expertise. This industry will bring overall improvements in project time, quality, cost, and safety standards as well as client requirements and satisfaction. This research paper is of the view that digitalization will increase productivity and the competitive advantage in the Construction industry. In conclusion, there is a need to prioritize investment in digital tools and technology to have ease of adoption of procurement digitalization.