Magdeburg, Universiẗat, Diss., 2003.

Bochum, University, Diss., 2002.

Thesis (M.S.)--Oregon State University, 1985. / Typescript (photocopy). Includes bibliographical references (leaves 105-108). Also available on the World Wide Web.

No description available.

Sediment bedload transport and bedform formation are considered for both steady and oscillatory flow of water. Some new theoretical results are quoted and experimental results are reported which tend to substantiate the theory. For steady flow, criteria based on Froude number and mean velocity are developed for predicting the types and dimensions of bedforms which occur under various flow conditions and different sediment properties. The flow depth is found to be an important variable linking Froude number with the mean velocity. For oscillatory flow, general agreement is found with the work of Mogridge and Kamphuis and the earlier work of Bagnold. The free surface wave parameters and the water flow depth are confirmed to be dominant factors in determining ripple characteristics. The experimental results give some confirmation of a new kinematic model proposed to explain sediment ripple behavior. / Applied Science, Faculty of / Civil Engineering, Department of / Unknown

In South Africa, the legacy of apartheid planning established vast differences within cities in terms of household income, consequently, the population in different areas are exposed to varying road environments. These road environments include, for instance, the mode usage of the population that exposes them to varying traffic conditions. The literature suggests that there is a need to understand road fatalities further, so as to articulate informed interventions by determining the impact of these environments on road fatalities, at a more disaggregated level than that of cities. With road fatality levels remaining high within the country, this study aims to perform this disaggregated study for Cape Town. In this study, Cape Town fatality data for the 2011-2015 period was analysed on a 2013 Traffic Analysis Zone level, defined in this study as the analysis district. The analysis included determining absolute fatalities and fatality rates, comparing mode usage with fatalities, and imputing the mode involved in fatalities. Geocoded data was also used to extract the top 10 hazardous zones in the city by ranking them based on the number of road fatalities and describing the fatality conditions in the top three zones. Analysis revealed that pedestrians constitute the majority of road fatalities in the city (58%) and all analysis districts. Furthermore, the low-income districts had a high road fatality burden per annum, but a low fatality rate that was comparable to high-income countries. Alternatively, high-income districts had a low road fatality burden per annum, but a high fatality rate. It was also found that percentage fatalities that impact pedestrians and cyclists are more than the percentage of the population that walk and cycle in the city. In terms of modes involved in fatalities, the Forensic Pathology Services data contained a large percentage of missing data (54%) hence, the analysis showed inconclusive results. Lastly, geocoded data revealed that the top three hazardous zones in the city - N1 and N7 junction, Table Bay Boulevard (N1) and M30 and R101 junction - continue to impact pedestrians crossing highspeed arterials. The dataset also suggested that risky driver behaviour and lighting is a major problem in these zones. From the results, it can be inferred that the prescribed interventions need to target pedestrian fatalities at both an aggregated and a disaggregated level. In the case of the hazardous zones, these localised interventions need to include reducing speed limits along residential roads, providing adequate lighting and creating safe pedestrian crossing facilities along desire lines. Moreover, both, average annual fatalities and fatality rates, need to be determined when prioritising areas for road safety measures. Lastly, given the percentage of missing data, the fatality burden in the city is underrepresented, which suggests there is a need to improve data capturing in the field. While this study has been adopted towards the Cape Town context, the principles of this study can be implemented in countries with high fatality burdens, which mainly include low- and middle-income countries.

Public transport provision in South Africa is set to change dramatically in the coming years if the plans and strategies of Government come to fruition. Policy clearly states that the needs of the end user of public transport services and facilities have to be prioritised, and that transport systems will be overhauled to provide a range of integrated trunk and feeder services, in emulation of the successes achieved in the so-called public transport 'model cities' of South America. However, it is not certain whether the range of public and private institutions involved in the planning, implementation and operations of public transport at the local level are ready to respond effectively to the policy requirements. Institutional fragmentation is the order of the day, public transport services are largely peak-time, commuter based services, and the minibus taxi industry remains effectively unregulated. The experience of public transport users, if measured by the efficiency of transferring between services at public transport interchange facilities, is of a very poor quality, and the design and planning guidelines for these facilities do not offer much insight into how this situation can be rectified. This dissertation provides two insights in view of the current challenging public transport reality. Firstly, it investigates the link between institutional integration, and whether such integration has an effect on the experience of public transport users at interchanges. Secondly, it critically analyses the existing design and planning guidelines for public transport interchanges to explain why these documents do not seem to lead to improved physical integration between transport services, and ultimately an improved experience for the person wishing to transfer between those services. These links are tested by developing a framework that assesses the obstacles that reduce the efficiency of user transfers between services at interchanges, and it applies this framework at interchange sites in Cape Town in South Africa, and Curitiba and Sao Paulo in Brazil. The findings, when compared between sites and cities, lead to the formulation of recommendations regarding the expectations surrounding institutional integration and the provision of more effective design and planning guidelines for public transport facilities.

Includes bibliographical references. / This thesis discusses the infrastructural, vehicular and environmental factors that contribute towards road accidents. The role of infrastructure in improving road safety is the primary focus of the research, as infrastructure influences the driving experience. Road design and geometry are important for the consistency of highway performance. Road curvature, paved shoulders and the presence of an at grade intersection influence the drivers’ perception of the highway. The Laingsburg Beaufort West N1 highway has a high incidence of accidents, namely single vehicle accidents. For this reason, the road section has been classified as a hazardous location. These fatal accidents may be influenced by the infrastructural and geometrical factors of the highway. Western Cape geographical data was analysed for the period 2000 to 2007, to investigate the infrastructural and geometrical factors that influence the high accident rate. This was done through an ArcGis analysis, which gave insight into the properties of each of the fatal accidents. In order to get a level of confidence from the findings of the ArcGis analysis, a road safety audit was conducted. This was done through a general inspection of the N1 highway between Laingsburg and Beaufort West, which included driving through the road section at a constant speed, and completing a checklist of the operating elements of the highway. The road safety audit revealed that infrastructural problems (lack of guardrails, sign posts located close to highway) and geometrical factors (average paved shoulder width, single carriageway roads, and dangerous intersections) were present on the road. The Laingsburg Beaufort West analysis was the primary focus of the research. Data for the years 2010 to 2013, which was updated, was obtained from SANRAL and investigated for accident types and potential hotspots. An ArcGis analysis was also performed on the data. Fatal accidents were analysed, to determine whether the Provincial Government of the Western Cape would meet their accident reduction goals of reducing accidents by 50% between the years 2009 and 2014. A high incidence of fatal pedestrian accidents was observed in the Khayelitsha area. Recommendations include the relocation of poles and signs, increasing the paved shoulder width, installation of guardrails along the entire highway, as well as provision of pedestrian bridges and walkways in the Khayelitsha area.

Includes abstract. / Includes bibliographical references. / During December (2007), Cape Town’s peak tourism season, a pilot pedestrianisation project was run in the City of Cape Town. The 300 year old Greenmarket Square was pedestrianised and stakeholders on the square were surveyed six months after the implementation of the scheme to access the economic benefits, as well as the perception of predestination by the traders. A SATURN dynamic assignment model was used to simulate the effect of certain road closures to traffic as part of an extension to the pedestrian network. These road are vital to start forming a formalise pedestrian network within the CBD. From the results, a pedestrian network for the Cape Town CBD has been proposed.

The choice of travel mode for the journey to work is an important aspect in the planning of adequate transportation systems in urban areas. This choice process is complex and consequently a generalized theoretical basis for modal choice is difficult to construct. Nevertheless, empirical modeling of modal choice behaviour has enabled transportation planners to predict future travel demands for different modes. Furthermore, such models have led to a body of knowledge which has allowed researchers to explore the modal choice decision on a more theoretical basis. This study involves the analysis of the modal choice process for White commuters in Cape Town. The investigation of the role of modal split in transportation planning is provided to illustrate the relevance of this sub-process in the overall transportation planning process. An investigation of some of the theoretical and applied literature in this field indicates, that to obtain suitable and simple planning tools for modal split analysis, an empirical approach to modelling is probably the best alternative. The theoretical approaches are still in an embryonic stage and require more research before they offer a practical solution to modal split modelling. The data collection technique used in this study involved the distribution of a questionnaire survey to a sample of employees at their workplace. The technique provided an excellent response rate and can be performed with a minimum of resources. Other detailed travel time studies are described and once again all appreciable amount of data was able to be collected with a minimum of funds and manpower.