Academic submissions (CEDAT)
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ItemImpact of project management on construction supervision: a case study of St. Noah Nfuufu Road (2.0km) in Makindye Ssabagabo Municipality, Wakiso District(Makerere University, 2025)Effective project management plays a vital role in the successful execution and supervision of construction projects, particularly in the public infrastructure sector where accountability, resource limitations, and stakeholder expectations are critical. In Uganda, many road construction projects face challenges such as delays, cost overruns, and quality issues often linked to weaknesses in project management and site supervision. This study examined the impact of project management practices on construction supervision, using the St. Noah Nfuufu Road project (2.0 km) in Makindye Ssabagabo Municipality, Wakiso District, as a case study. The research aimed to assess how core project management principles particularly in time, cost, quality, stakeholder, and communication management were applied in practice, and how they influenced project outcomes. A case study research design was adopted, utilizing document review and field observations. Data analysis was both thematic and descriptive, aligning findings with the Project Management Body of Knowledge (PMBOK) framework and Uganda’s national road construction standards. The findings revealed that while formal project management structures were in place, their application was often adapted to local realities, including resource constraints, political pressure, and stakeholder dynamics. Time and cost control were challenged by delayed disbursements and scope variations, while quality assurance and stakeholder engagement proved to be critical factors in maintaining progress and minimizing resistance. The study concludes that effective supervision, proactive stakeholder involvement, and consistent documentation practices significantly enhance project delivery even in resourceconstrained public works environments. It recommends improved early-stage planning, the use of digital tools, strengthened site supervision, and better testing infrastructure as key strategies for enhancing construction project outcomes in similar contexts.
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ItemRadio resource management and scheduling for machine type communications(Makerere University, 2025)In recent years, the rapid growth of Machine Type Communications (MTC) within the Long Term Evolution (LTE) networks has introduced significant challenges in managing radio resources efficiently. MTC, characterized by massive device connectivity and diverse Quality of Service (QoS) requirements, competes with Human Type Communications (HTC), leading to high collision rates, increased delays, and sub-optimal resource utilization. Conventional LTE mechanisms, such as Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), Slotted Aloha, and Proportional Fairness (PF), are limited in their ability to manage contention, allocate bandwidth dynamically, and adaptively address the QoS requirements of heterogeneous MTC applications. This thesis addresses these challenges by proposing and evaluating three novel mechanisms, namely: Hybrid Access Control (HAC), Dynamic Priority-based Bandwidth Allocation (DPBA), and Adaptive QoS Differentiation (AdaQoS). HAC integrates Dynamic Resource Allocation, Slotted Aloha, and CSMA/CA, achieving an 86% reduction in collision rates, a 91% decrease in access delays, and an 82% improvement in energy efficiency compared to conventional access control methods such as Slotted Aloha and CSMA/CA. DPBA introduces a dynamic bandwidth allocation scheme that prioritizes devices based on their specific requirements, resulting in a 25% improvement in throughput, a 30% reduction in latency, a 43% improvement in fairness, and 50% reduction in packet loss rate compared to existing bandwidth allocation strategies like PF, Machine Learning based Scheme (MLS) and Static Priority Scheduling (SPS). AdaQoS dynamically adjusts resource allocation to meet the specific QoS needs of MTC applications, achieving a 55% increase in scalability, a 35% improvement in fairness, a 24% boost in security, and a 54% improvement in Energy Efficiency (EE), surpassing existing machine learning-based QoS differentiation schemes. By reducing contention, optimizing bandwidth allocation dynamically, and adaptively catering to diverse QoS requirements, these mechanisms collectively enhance the efficiency, reliability, and scalability of MTC communications within LTE and beyond networks. The findings highlight their potential to optimize the coexistence of MTC and HTC, paving the way for robust and future-ready wireless communication infrastructures.
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ItemUp cycling of steel slags in cement production(Makerere University, 2025)Steel slag, a by-product of the steelmaking process, poses significant environmental challenges due to its large volume and potential for environmental harm if improperly managed. This research explored the feasibility of integrating steel slag as a raw material in cement production, with a focus on its chemical composition, physical properties, and performance in cementitious applications. Randomly sampled steel slag was mixed with pozzolana, gypsum, and clinker in varying proportions, replacing clinker at percentages ranging from 5% to 20%. The formulated mixtures were then milled into a fine powder using a ball mill to produce steel slag cement. The chemical composition and fineness of the resulting cement were determined using X-ray fluorescence (XRF) analysis and the Blaine test, respectively. Cement paste and prisms were subsequently prepared to evaluate the physical properties of the cement. The standard consistency, setting time, and soundness of the cement paste were assessed using the Vicat apparatus which determines the water content, and Le Chatelier’s test which determines the expansion extent. Additionally, the compressive and flexural strengths of the cement prisms were measured using a universal testing machine. The chemical composition of slag and other raw materials showed high concentrations of CaO, SiO2, and Al2O3, with variations across samples. Fineness of cement increased with steel slag, enhancing early hydration but not necessarily strength. Consistency decreased with increase in steel slag, reducing water demand. The initial and final setting times for cement samples increased with increase in steel slag, giving a peak time at 20% slag with 301.5 and 405 minutes, correlating with the SiO2/Al2O3 ratio and cement particle size. Compressive and flexural strengths generally decreased with decrease in steel slag, though some improvements were noted at 28 days. Results showed that the chemical properties of steel slag were found to be similar to standard cement raw materials as outlined in US EAS 148-2, 2017 standard and physical tests confirmed that steel slagbased cements meet established standards for setting time, soundness and compressive strength as per US EAS 18-1, 2017 standard. Steel slag can be effectively used in cement production up to 15% by mass. Further studies are recommended for alternative soundness testing methods to accurately assess MgO-induced expansion, as well as performing a cost-benefit analysis to evaluate the financial viability of replacing clinker with steel slag in cement production.
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ItemInfluence of filler-to-total bitumen ratio on mastic properties and moisture susceptibility of bituminous mixtures(Makerere University, 2025)The performance and longevity of asphalt pavements are significantly influenced by the quality of bituminous mastics, which consist of bitumen and fillers. While the mastic phase constitutes a smaller proportion of the overall asphalt mixture, it plays a crucial role in determining the mixture rheological, durability, cohesion and adhesion properties. The choice of bitumen, filler and their proportions impact mastic’s effectiveness. Whereas there has been considerable research focused on the interaction of neat bitumen with aggregates, there remains a significant knowledge gap regarding the role of mastics in asphalt mixtures, particularly in relation to stripping and ageing. Thus, this study sought to evaluate the influence of filler-to-total bitumen ratio on mastic physical properties and moisture susceptibility of bituminous mixtures. The research focused on characterizing the study materials, determining the effects of material type, proportion and short-term ageing path on mastic physical properties and the implication of mastics on stripping in bituminous mixtures. The results revealed that mastic stiffness increased with increasing filler-total bitumen ratio, but their temperature susceptibility decreased. The ageing path did not significantly impact mastic physical properties. Rock dust mastics were less resistant to stripping in comparison to the other filler mastics. The chemical-elemental properties of hydrated lime, mollusc shell fines and fly ash, which are categorized as active fillers, enhanced the adhesion of their mastics to the aggregates due to the chemical reaction between alkaline components (Ca+ ) in them and bitumen acidic components mainly carboxylic acids (-COOH) and phenols (-OH). The poor adhesion (high moisture damage susceptibility) of rock dust mastics was attributed to the acidic nature of rock dust filler owing to its high silica content. When carefully selected and controlled, alternative active fillers have the potential to improve the performance, durability and cost-effectiveness of bituminous mixtures in Uganda’s tropical environment. Their use aligns with local resource availability, climatic conditions and sustainability goals. However, quality assurance, specifications and capacity building need to accompany their adoption.
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ItemA comparison of design and actual traffic levels and its likely impact on the pavement premature failure : case study of Gulu – Atiak – Nimule Highway(Makerere University, 2024)The Gulu-Atiak-Nimule highway was constructed and completed to a flexible pavement standard in the year 2015 and opened to traffic that traverses this highway from mainly Kenya, Tanzania via Uganda to South Sudan. The anticipated increase in traffic volumes and especially heavy axle load trucks might have brought the road pavement to a premature failure. The road is currently short of its structural capacity, highly distressed and showing signs of failure. This is affecting the flow of traffic and increasing operational costs coupled with the fact that a number of accidents have been reported resulting from a number of distresses such as potholes, cracks, edge shoulder drops, rutting, ravelling, and failed sections of the road. This research study involved carrying out traffic surveys, axle load surveys and road condition assessment surveys. The traffic surveys involved manual classified seven consecutive day count for 12 hours and 24 hours. The 24-hour count was carried out for 2 days, with 1 day within the week and 1 other day within the weekend. The axle load survey was done at the fixed weighbridge at Elegu near the South Sudan boarder. The condition assessment was undertaken using the ASTM D6433 method that involved visual inspections and recording of distresses observed on the pavement surface and qualifying them. Results from the study indicated that the current Average Daily Traffic (ADT) and Average Annual Daily Traffic (AADT) are 2604 and 2939 Vehicles per day respectively. Heavy traffic alone consisting of mainly truck trailers and semi-trailers constituted 29% of the total traffic volume. The Cumulative Equivalent Million Standard Axle for the year 2024 was calculated and obtained as 1.285million ESA which is a T3 Traffic Design Class. The comparison of these volumes to that considered at design reflected a traffic growth rate of 14% and yet that at design, the growth rate was taken at 6% per year for the first 10years. The axle load survey results indicated that the average weigh of heavy traffic was 43.025tons and this generated a damaging factor to the pavement of 2.973. The pavement condition evaluation carried out, indicated that the Pavement Condition Index and International Roughness Index for the Gulu–Ataik sectional link was 38 and 4.0m/km respectively; while that of Ataik –Nimule section registered PCI and IRI of 64 and 3.5m/Km respectively. This study has revealed that the current traffic volume is high totalling to 2604vpd, with 29% of this being attributed to heavy traffic and therefore increased million standard axles. The section from Gulu–Ataik was in a poor condition and hence required rehabilitation to further extend the pavement life; while that of Atiak-Nimule was in a fair to good condition and required routine maintenance.