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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Geomorphic considerations in the deterioration of rural roads : the case of Inkandla, Indwedwe and Ga-Modjadji.

Khandlhela, Nkhensani. January 2003 (has links)
The condition of the rural road network in South Africa is in a severe state of deterioration and remains a matter of concern for inhabitants of rural areas. Apart from heavy use, the main problem is that road development is often neglected and the main focus is placed on the geomorphic environment. The objective of this study is to identify the nature of the geomorphic constraints of vehicular access on unarmoured roads in the rural areas of KwaZulu Natal and the Limpopo Province of South Africa, and to gain a better understanding of how these function. It is hoped that some of the insights gained can then be used to inform policy decisions regarding the location and design of rural roads in the future. In this study, a number of unarmoured roads were studied in detail to identify the possible environmental constraints on vehicular access. A number of soil physical and chemical properties were used to examine the state of road degradation. These properties included particle size analysis, soil strength, Cation Exchangeable Capacity and Exchangeable Sodium Percentage. The results of the investigation of soil properties have shown that they play a significant role in road degradation. The major geomorphic factors involved in road deterioration include soil type, soil erosion and precipitation characteristics, mass movements, slope conditions and human activity. The physical characteristics, especially the soil and slope conditions, make the access roads in all study areas susceptible to soil loss. Factors such as geology, drainage and friable soils vulnerable to mass movements have been identified as seriously constraining vehicular access. Soil erosion problems in the study area are largely the result of physical and chemical properties of soils combined with steep gradients and have been identified as the primary cause of road degradation. It was further found that the socio-economic conditions, together with the anthropogenic influences such as the construction of rural access roads on vulnerable slopes, population density and the removal of vegetation cover in all the study areas have significantly enhanced road deterioration. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
2

Implementation of road infrastructure development projects in rural areas of South Africa : a case of Polokwane Municipality in Capricorn District

Mamabolo, Malemela Angelinah January 2013 (has links)
The South African government is obliged to render basic services for the people through local government municipalities. These basic services include among others the development of adequate roads, clean water and electricity. The responsibility of the delivery of these services was given to the municipality after the 1994 general elections, with the belief that it is the government that is closer to the people on the ground than the national and provincial governments. The issue of the provision of quality roads in rural areas of South African still remains a critical challenge. The issue addressed in this study is the provision of quality roads provided in Polokwane Municipality. The study focused on the implementation of roads infrastructure development project in rural areas of South Africa and the provision of roads in the rural areas of Polokwane Municipality in Capricorn District, with a special focus on the provision of roads in the rural villages of Thabakgone, Komaneng, Segopje and Ga-Molepo. The study used data collection instruments such as interviews, questionnaires and supporting documents, such as Polokwane Integrated Development Plan and relevant scientific articles to collect data in the four selected villages. The findings of the study revealed that the provision of roads infrastructure in the municipality is of substandard quality, and that the provision of quality roads in the areas is required.
3

Establishing and applying speed-flow relationships for traffic on rural two-lane two- way highways in the Western Cape

Twagirimana, Janvier 12 1900 (has links)
Thesis (MScEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Speed-flow-density relationships are the most useful tools in the highway design and planning process. They are useful in predicting the roadway capacity, in determining the adequate level-of-service of traffic flow and in determining travel time for a given roadway. Two-lane two-way rural highways constitute the vast majority of the rural road network in South Africa. Nowadays in the Western Cape and other provinces of South Africa, the speed-flow-density relationships normally used for rural transportation studies are derived from the Highway Capacity Manual, which reflects the traffic conditions in the North American situation. Since the North American traffic conditions may be different from the South African conditions, a need to investigate speed-flow-density relationships on these highways in South Africa arises in order to justify any investment made on these roads. In this context, a video technique was used to collect traffic flow data during morning peak hours on two rural two-lane two-way highways in the Western Cape Province in order to investigate these relationships. Through the use of Adobe premiere C.S 6 software, travel time of individual vehicles and distance headways were measured and used in computation of average speed and average density. Several researchers have developed models to describe the relationships between traffic characteristics on uninterrupted flow facilities. In this study, some of these models were tested using collected data in order to investigate which model fits the data satisfactorily. Statistical methods were used to evaluate the ability of each model to predict the flow characteristics over the whole range of data. Average speed and density data were used through regression analysis to perform curve fitting and testing of these developed models. In the next stage, the model which provided a best representation of the data on each section was selected and through the application of the steady-state equation (2.1), flow-density and speed-flow relationships were established on these sections. The available data were also used to investigate the impact the observation time has on the speed-flow curve and the resulting capacity value. Finally, the developed speed-flow curves were used to determine the capacities of the study sections. These capacity values were used to determine if the shoulder usage contributes in increasing the capacity of two-lane two-way highways by comparing them to the capacity provided by HCM. / AFRIKAANSE OPSOMMING: Spoed-vloei-digtheid verhoudings is baie handig in die beplanning en ontwerp van paaie. Dit kan ook gebruik word in die voorspelling van kapasiteit, diensvlak en reistyd. Twee-laan twee-rigting paaie maak die grootste deel van die Suid-Afrikaanse padnetwerk uit en vir die beplanning daarvan word van Amerikaanse spoed-vloei-digtheid verhoudings gebruik gemaak aangesien daar nog nie voorheen ‘n studie hiervan in SA gemaak is nie. Video-opnames is gebruik om verkeersvloeidata op twee paaie in die omgewing van Stellenbosch te versamel. Die reistyd en digtheid van individuele voertuie is tydens spitstye waargeneem. Die data is gebruik om te bepaal watter modelle die beste is om die spoed-vloei-digtheid verhoudings vir hierdie paaie te modelleer. Die beste modelle is dan gebruik om die kapasiteit van die paaie te bepaal en dit te vergelyk met die Amerikaanse waardes.
4

The effect of South African provincial road condition on the efficiency of forest product transport

Nicholls, Stephen John 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The context of the study is concern over declining provincial road condition due to insufficient government funding of road maintenance. These roads are by their public nature used by a wide variety of commercial and private interests contributing a variety of axle loads. There was no information available on the use of these roads by forest companies and the road conditions. Consequently a survey was conducted to determine condition and length of each segment of provincial road in use by forestry companies and the volume of wood transported over them. In addition data was gathered on other users and their contribution to the volume transported over each section. The questionnaire indicated that the provincial roads are in a poor state. The literature review suggested a significant reduction in total cost of transport can be achieved by maintaining or rebuilding these roads. South African forest companies provide the majority of the heaviest axle loading to these roads and must theretore take responsibility tor damage caused to them. Also a variety of forest companies use the same roads and consequently collaborative studies between companies are needed. A modified Dijkstra's algorithm was used to quantify the effect of the condition of South African provincial roads on the efficiency of the transport ottorest products. The model requires digitised raster road and forest map layers combined with transport vehicle specification as input. The products of the model are optimum routes from all source points to a single exit point or sink, the total volume transported across all road nodes and the total cost to extract all wood from a map section. This output allows managers to identify critical roads tor management attention and make tentative estimates of possible reductions to total cost by altering the road condition. The manager is able to test the sensitivity of the solution to changes in variables and gain a better overall picture of the interactions within the system. The model results, and improved understanding, will provide input to more specific and collaborative studies. South African forest managers can respond to the poor provincial road network by conducting ad hue maintenance to these roads to prevent them becoming completely impassable or to rebuild them to their design state and maintain them at that state. The cost of taking no actions is that these roads would eventually become impassable. The road network model determined that, for the study area, a unilateral decision to rebuild and maintain all roads would result in a net increase in transport costs ofR 2 million/year. When compared to the cost of ad hue road improvements for the same area of R 8 million it is obvious that proper road management is a better option. It was shown that 75% of the reduction in total cost is generated by improving only 31 % of the provincial road surface. Consequently, by improving selected roads (20% of the total provincial road network for the area) it was possible to generate a net cost R 2.9 million lower than if the roads were left as they are. If reductions in operating costs are included the net cost to the forest industry is R 3.1 million/year lower than leaving the roads as they are. In addition to the cost being lower, an improved road network would be in place and the current ad hue spending would be unnecessary. On a larger scale it was estimated that poor provincial road management costs the industry as a whole R 26 million or R 1.52/m3/year. This money can be used to offset the costs of maintaining and upgrading roads. It is therefore concluded that the South African forest industry needs to assess its policy on provincial road management and become more active in the managing of these roads. The tool developed and presented is intended as a prototype decision support tool in developing future policies. / AFRIKAANSE OPSOMMING: Die inhoud van hierdie studie handelaar die verval van provinsiale paaie as gevolg van die regering se onvoldoende fondse vir die instandhouding van die paaie. Hierdie paaie word as gevolg van hulle publieke aard deur 'n wye verskeidenheid kommersiële en private belange gebruik, wat bydra tot 'n verskeidenheid van asladings. Daar was geen inligting oor die bosbou maatskappye se gebruik van paaie of die toestand van die paaie beskikbaar nie. Gevolglik is 'n opname gemaak 0111 die kondisie en lengte van elke segment van die paaie wat deur die bosbou maatskappye gebruik word, vas te stel, asook die volume hout wat oor die paaie vervoer word. Data oor ander verbruikers van die paaie is verder ingesamel, asook hul bydrae tot die volume wat oor die paaie vervoer word. Die vraelys het aangedui dat die provinsiale paaie in 'n baie swak toestand is. 'n Literatuurstudie het getoon dat 'n beduidende daling in die totale vervoerkoste moontlik is deur hierdie paaie te onderhou afoor te bou. Die Suid-Afrikaanse bosbou maatskappye voorsien die meerderheid van die swaarste asladings op hierdie paaie en moet dus verantwoordelikheid neem vir beskadigde paaie, 'n Verskeidenheid bosbou maatskappye gebruik die paaie; gevolglik is gesamentlike studies tussen die maatskappye ook nodig. 'n Aangepaste Dijkstra algoritme is gebruik om die effek van die toestand van Suid- Afrikaanse provinsiale paaie op die effektiwiteit van die vervoer van bosbou produkte, vas te stel. Hierdie model benodig digitale inligting oor die hoofen bosbou paaie, asook die spesifikasies van die voertuie wat gebruik word. Die resultaat van die model is die optimale roetes vanaf alle bronpunt oorspronge tot by 'n enkele bestemming, die totale volume vervoer oor al die padnodusse en die totale koste verbonde aan die verwydering van alle hout uit 'n afgemerkte seksie op die kaart. Hierdie produk of result ate stel bestuurders in staat 0111 kritieke paaie vir aandag te identitiseer en om tentatiewe voorspellings van moontlike afname in die totale kostes te maak indien die toestande van paaie verbeter sou word. Die bestuurder kan die sensitiwiteit van die oplossing vir variasie in die veranderlikes toets en sodoende 'n beter geheelbeeld kry van die interaksie binne die sisteem. Die resultate van die model en n beter begrip daarvan, kan insterte lewer in meer spesitieke studies en gesamentlike studies tussen maatskappye. Suid Afrikaanse bosbou bestuurders kan teen die swak provinsiale padnetwerk optree deur ad hoc instandhouding toe te pas op hierdie paaie om te voorkom dat hulle totaal en alonbegaanbaar word. Ofhulle kan die paaie restoureer tot hul oorspronklike toestand en hulle dan in stand hou. Die kostes daaraan verbonde om nie op te tree nie, is dat hierdie paaie uiteindelik on-gaanbaar sal word. Die padnetwerkmodel het gewys dat vir die spesitieke studie area, 'n eenparige besluit 0111 alle paaie te herbou en onderhou, 'n algehele toename in vervoerkostes van R2 miljoen/jaar tot gevolg sal hê. Wanneer dit vergelyk word met die R8 miljoen wat die ad hoc padverbeterings kos, is dit duidelik dat geskikte padbestuur 'n beter opsie is. Daar is bewys dat 75% van die daling in totale kostes genereer kan word deur verbeteringe aan die oppervlaktes van slegs 31% van die provinsiale paaie te maak. Gevolglik was dit moontlik om netto kostes van R2,9 miljoen ruinder te genereer as vanneer geen instandhouding gedoen is nie. Dit is bewerkstellig deur verbeteringe aan geselekteerde paaie aante bring (20% van die totale provinsiale padnetwerk vir die area.) As die daling in bedryfskoste ingesluit is, sal die netto koste vir die bedryf R3.1 millioen/jaar ruinder wees as om die paaie so te los sonder enige aandag. Verder, tot laer koste sal daar 'n verbeterde pad netwerk in plek wees en die huidige ad hoc spandeering aan die paaie nie meer nodig wees nie. Op groot skaal, is die benaderd voorspelling dat 'n swak provinsialepadbestuurstelsel die bosbou bedryf R26 millioen of R 1.52/m3 uit die sakjaag. Hiedie misbruikde geld kan eerder teruggeploeg word in pad onderhoud en opgradeerings werksaamhede. Dit is dus nodig dat die bosbou bedryf sy beleid weer in oonskou moet neem in verband met die bestuur van provinsiale paaie en ook meer aktief die voortou sal moet neem in die instandhoudind van provinsiale paaie. Die metodiek hier ontwikkel kan 'n inleidende doel dien in die ontwikkeling van toekoemstige besluit neeming rakend die bestuur van provinsiale paaie.
5

Childhood pedestrian mortality in Johannesburg, South Africa : magnitude, determinants and neighbourhood characteristics

Bulbulia, Abdulsamed 11 1900 (has links)
Child pedestrian injury and mortality is an issue of significant public health concern in the city of Johannesburg, Gauteng, in South Africa. Since there is a paucity of studies in the last decade or more on fatal childhood traffic and non-traffic injuries in Johannesburg, this study aspires to address the disproportion in this domain of research, and provide more recent, and comprehensive empirical evidence over a ten-year period. The overarching aim of this study was to describe and examine the magnitude, circumstances, and neighbourhood characteristics of fatal pedestrian injuries among children (0-14 years) in Johannesburg for the period from 2001 to 2010. More specifically, the objectives of the study were: firstly, to provide a comprehensive epidemiological description of the magnitude, trends and occurrence of pedestrian mortality among children; secondly, to describe and examine the epidemiology of child pedestrian mortality in relation to children as motor vehicle passengers; thirdly, to describe and examine child pedestrian mortality in relation to non-traffic injuries, in particular, burns and drowning; and fourthly, to assess the influence of neighbourhood characteristics on child pedestrian mortality. The study conceptualised pedestrian road safety within an ecological systems framework. The study used quantitative descriptive, and multivariate logistic regression methods of analysis to examine child pedestrian mortality data. The study drew on data from the National Injury Mortality Surveillance System (NIMSS) and the Census 2001. The main findings indicated that black, male children aged 5 to 9 years (11.02/100 000) are the most vulnerable, and that mortality occurred predominantly during the afternoons and early evenings (12h00-16h00 and 16h00-21h00), over weekends, during school holidays, and to a lesser extent, during non-holiday months. In addition, neighbourhood characteristics that reflected concentrations of disadvantage, single female-headed households and residentially stable areas were associated with child pedestrian mortality. The study findings highlight the need for critical action in terms of investment in child pedestrian safety research, and appropriate prevention initiatives guided by stringent evidenced-based studies, and the design of safe pedestrian, vehicular and urban environments. / Psychology / D. Phil. (Psychology)
6

Childhood pedestrian mortality in Johannesburg, South Africa : magnitude, determinants and neighbourhood characteristics

Bulbulia, Abdulsamed 11 1900 (has links)
Child pedestrian injury and mortality is an issue of significant public health concern in the city of Johannesburg, Gauteng, in South Africa. Since there is a paucity of studies in the last decade or more on fatal childhood traffic and non-traffic injuries in Johannesburg, this study aspires to address the disproportion in this domain of research, and provide more recent, and comprehensive empirical evidence over a ten-year period. The overarching aim of this study was to describe and examine the magnitude, circumstances, and neighbourhood characteristics of fatal pedestrian injuries among children (0-14 years) in Johannesburg for the period from 2001 to 2010. More specifically, the objectives of the study were: firstly, to provide a comprehensive epidemiological description of the magnitude, trends and occurrence of pedestrian mortality among children; secondly, to describe and examine the epidemiology of child pedestrian mortality in relation to children as motor vehicle passengers; thirdly, to describe and examine child pedestrian mortality in relation to non-traffic injuries, in particular, burns and drowning; and fourthly, to assess the influence of neighbourhood characteristics on child pedestrian mortality. The study conceptualised pedestrian road safety within an ecological systems framework. The study used quantitative descriptive, and multivariate logistic regression methods of analysis to examine child pedestrian mortality data. The study drew on data from the National Injury Mortality Surveillance System (NIMSS) and the Census 2001. The main findings indicated that black, male children aged 5 to 9 years (11.02/100 000) are the most vulnerable, and that mortality occurred predominantly during the afternoons and early evenings (12h00-16h00 and 16h00-21h00), over weekends, during school holidays, and to a lesser extent, during non-holiday months. In addition, neighbourhood characteristics that reflected concentrations of disadvantage, single female-headed households and residentially stable areas were associated with child pedestrian mortality. The study findings highlight the need for critical action in terms of investment in child pedestrian safety research, and appropriate prevention initiatives guided by stringent evidenced-based studies, and the design of safe pedestrian, vehicular and urban environments. / Psychology / D.Phil. (Psychology)

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