Department of Civil and Environmental Engineering

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Browsing Department of Civil and Environmental Engineering by Subject "Assessment"

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    Assessement of the impact of sawdust ash on the sulphate resistance of concrete during early strength development
    (Kyambogo University, 2020-12) Basajjansolo Babiito, Patrick
    Sulfates are detrimental to the structural integrity of concrete throughout its service life. In the project for the construction of the overhead transmission line grid for power evacuation from the Karuma Hydro Power plant, aggressive levels of sulfates were encountered along Karuma – Lira 132kV Transmission Line. This necessitated use of Sulfate Resisting Cement (SRC) in foundations to counter sulfate attack. Sulfate Resisting Cement is twice as expensive as Ordinary Portland Cement (OPC) in Uganda and may only be available on a minimum special order of 200 tons. Based on the above the study was therefore aimed at evaluating the impact of sawdust ash on the sulphate resistance of concrete during early strength development. A total of 384 concrete cubes of 4 designed mixes were used in two different sulphuric acid solutions of differing concentrations to simulate sulphate attack on concrete. Cubes were exposed to sulfate attack for 28 days in sulphuric acid solutions in the early stages of hardening (i.e., at the age of 6, 24 and 72 hours) and in the later stage of hardening (i.e., aged 28 days). SDA dosages used to replace part of the OPC were 0%, 5%, 10% and 15%. It was observed that concrete in the early stages of hardening (i.e., age of 6, 24 and 72 hours) exhibited improved resistance to sulfate attack compared to that in the later stage of hardening (i.e., aged 28 days). Moderate strength concrete grades (i.e., C16/20, C20/25) with design cement content less than 18.1% performed better than the higher strength concrete (i.e., C25/30 and C30/37). The ingress of SO4 2- ions into C20/25-5% SDA concrete followed a decreasing linear function for concrete cured for 72 hours before exposure to sulfate attack. A maximum cement replacement of 10% with SDA as well as partial back filling of foundation concrete after 72 hours of casting is
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    Assessment of factors influencing performance of road construction projects in Uganda: a case study of ministry of works and transport
    (Kyambogo University, 2020-02) Seninde, Stephen
    The road construction projects in Uganda suffer from many problems and complex issues in performance such as; cost, time, scope and quality. The aim of this study was to assess the factors influencing performance of road construction projects in Uganda. The study adopted a descriptive research design and data were collected using questionnaires from 147 purposively selected respondents from Local construction companies, consultancy firms, and government officials from Ministry of Works and District Local governments. Relevant literature was reviewed to establish actual factors influencing performance of road construction projects in Uganda. Data were coded and entered into statistical packages for social scientists (SPSS) version 25. A total of 43 performance factors were identified and categorized into five factor groups. The data were analyzed descriptively using statistical correlation and regression analysis, multi-variate analysis and relative importance index (RII) was used to rank the identified factors. The study revealed five most significant and influential factors; contractors, clients/owners, contractor’s ability to mobilize to site, availability of funds, and cash flows, and three least influential factors; inadequate mobilization of resources, inadequate geotechnical and hydrological studies and lack of equipment. The study concluded that; contract management factors, project stake holders’ factors, and project financing factors significantly influence the performance of road construction projects in Uganda. The research study also recommended among others; setting aside finances for the project before commencement, putting in place competent supervision team for contract management, ensure fair and transparent procurement processes for proper performance of road construction projects. Key Words: Assessment, Performance, Road construction projects, relative importance index.
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    Developing a maintenance management system for public buildings in district local governments of Uganda: a case of amuria district local government
    (Kyambogo University [unpublished work], 2020-11) Elolu, Eonya Julius
    The practice of building maintenance is globally accepted as the most sustainable way to conserve buildings from deterioration. In most developing countries, costs incurred for assessment, repair and maintenance of buildings are principally met by the local governments other than insurance companies and yet the former have insufficient funds to cater for the challenges of maintenance of buildings. This study sought to develop a maintenance management system for public buildings in District Local Governments of Uganda. Published literature on building maintenance management systems, condition survey index, defects severity and their priorities on the need to rectify was reviewed. The methodology used in this study had mechanisms of collecting both primary and secondary data sources that included key informant interviews, observations, inspections and desk studies. The maintenance management system was used determine the components to be maintained by ranking. This was premised on the severity of defects using a Multi-Criteria Decision Model (MCDM) that was based on the principals of Fuzzy Analytical Hierarchy Process (FAHP). During the study, condition assessment of buildings was conducted using an assessment tool and the staff that were involved in the management of buildings were interviewed. The findings showed that visual observation was the common mechanism used for condition assessment of building components due to the limited allocation maintenance activities in the development budgets. The common defects that affected components of the buildings were mostly cracks, surface deterioration, moisture ingress and debonding which was attributed to the social behavior of users and environmental factors. Most components were in good condition that required regular routine maintenance and a few were dilapidated and required immediate attention. This study recommended that District Local Governments need to establish the Maintenance Management System and regularly conduct condition assessments to inform the planning and budgeting of the built asset portfolio. Key Words: Maintenance, Defects, Components, Assessment, Management System