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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.
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Avaliação de prioridades relativas à não conformidades ambientais para empreendimentos rodoviários em fase de instalação / Assessment of priorities related to environmental nonconformities for road projects under constructionCiciliato, Rafael Coelho 07 October 2016 (has links)
Empreendimentos rodoviários causam impactos significativos nos ecossistemas e no meio físico adjacentes. Assim, a supervisão ambiental em empreendimentos rodoviários tem for finalidade verificar o cumprimento de exigências legais e operacionais, principalmente, durante a fase de instalação que corresponde ao período de obras. A definição e a importância relativa das variáveis a serem utilizadas no processo de conformidade ambiental é um processo imprescindível para a tomada de decisões. O método de Análise Hierárquica de Processos (AHP) é um instrumento de apoio à tomada de decisão, que tem o foco de fornecer ao decisor informações relevantes com relação a um conjunto de escolhas, de modo a auxiliar na definição da melhor ou mais relevante alternativa para o problema em questão. Nesse sentido, a presente dissertação objetiva fornecer subsídios as Concessionárias de Rodovias, Agências governamentais e Órgãos fiscalizadores para supervisão ambiental de rodovias como forma de analisar e priorizar aspectos ambientais e normativos, por meio da aplicação do método AHP a partir da expertise de profissionais envolvidos na gestão ambiental de rodovias. Para este trabalho foram definidas como critérios para supervisão ambiental as áreas relativas ao licenciamento ambiental, produtos perigosos, efluentes líquidos, segurança do trabalho, poluição atmosférica, resíduos sólidos, biótico e processo de dinâmica superficial, com análise de importância por pesos de 22,27%, 15,56%, 11,92%, 11,92%, 9,76%, 9,54%, 9,48% e 9,46, respectivamente. Para todos os cálculos dos vetores dos critérios e subcritérios o valor da razão de consistência foi menor que 0,1, o que indica que os resultados obtidos apresentam valores consistentes de análise comparativa. / Road projects have significant impacts on ecosystems and the surrounding physical environment. Thus, environmental supervision in highway projects has for objective to verify the compliance with legal and operational requirements, particularly during the installation phase that corresponds to the period of works. The definition and relative importance of the variables to be used in the environmental compliance process is an essential process for decision making. The Hierarchical Analysis Method Process (AHP) is a tool to support decision-making, which is the focus of providing the decision-maker relevant information with respect to a set of choices, in order to assist in defining the best or most relevant alternative to the problem in question. In this sense, this dissertation aims to provide subsidies the Highway Concessionaires, government agencies and oversight bodies for environmental supervision of highways as a way to analyze and prioritize environmental and regulatory aspects, by applying the AHP from the professional expertise involved in environmental management of highways. For this study were defined as criteria for environmental stewardship areas related to environmental licensing, dangerous products, wastewater, safety, air pollution, solid waste, biotic and surface dynamic process, with important analysis for 22.27 pesos %, 15.56%, 11.92%, 11.92%, 9.76%, 9.54%, 9.48% and 9.46, respectively. For all calculations of vectors of sub criteria and the value of the consistency ratio was less than 0.1, indicating that the results obtained are consistent values for comparative analysis.
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Guidelines for spacing of priority controlled intersections along urban collector roadsVisser, Salomé January 2007 (has links)
Thesis (M. Tech.) - Central University of Technology, Free State, 2007
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Mega project analysis : a case study of the Gauteng Freeway Improvement ProjectParrock, Philip 04 1900 (has links)
Thesis (MA)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Mega projects have fascinated human beings for as long as history can remember. The urge to build something bigger and better than has ever been done before has always been a driving force behind the human race’s relentless pursuit of technological advancement.
It is in this vein that mega projects have evolved over time, as methods of construction improved, so did the scale on which people could attempt new projects. The Channel Tunnel between England and France, the Hoover Dam in America and the Millau Viaduct in the French countryside are some of the biggest examples of infrastructure projects in the world and these are all unequivocally, mega projects. Costing at least $ 250 million and incorporating major technological challenges, mega projects continue to inspire and motivate artists and engineers alike.
This thesis seeks to expand people’s understanding of the analysis of these mega projects. Mega project analysis is a field that has struggled to differentiate itself ordinary project analysis. The Gauteng Freeway Improvement Project (GFIP) and the associated e-tolling mega project will be analysed in this thesis.
The framework for analysis will be provided by the work of Flyvbjerg, Bruzelius and Rothengatter (2003), who seek to analyse mega project success or failure based on three key indicators of economic sustainability, environmental concerns and the effect of public support. This thesis will use the indicators of economic sustainability and the effect of public support to determine whether the Gauteng Freeway Improvement Project (GFIP) can be viewed as a failed mega project or not.
After an in-depth study of the data and material available, this descriptive and explanatory study shows that the GFIP and associated e-tolling mega project is indeed a failed mega project. This is because it has failed the analysis in both categories of economic sustainability and the effect of public support. / AFRIKAANSE OPSOMMING: Megaprojekte het al eeue lank die mens gefasineer. Die neiging van die mens om iets groter en beter te maak as wat al ooit gemaak was het nog altyd baie dryfkrag verskaf vir die mens se strewe na tegnologiese verbetering.
Dit is met hierdie idee in gedagte dat megaprojekte met tyd verander het, soos wat boumetodes verbeter het, so ook het die grootte van projekte verander wat mense kon aanpak. Die Channel Tonnel tussen Engeland en Frankryk, die Hoover Dam in Amerika en die Millau Brug in die Franse platteland is voorbeelde van die grootste infrastruktuur projekte ter wêreld en hierdie is al drie, sonder enige twyfel, megaprojekte. Teen ‘n koste van ten minste $ 250 miljoen en met grootskaalse tegnologiese uitdaging, hou megaprojekte aan om vir beide kunstenaars en ingenieurs te motiveer en uit te daag.
Hierdie tesis poog om mense se kennis van die analise van megaprojekte te verbreed. Megaprojek analise is ‘n veld wat al jare lank sukkel om verskille te bewerkstellig tussen homself en gewone projek analise. Die “Gauteng Freeway Improvement Project” (GFIP) en die verwante e-toll megaprojek sal geanaliseer word in hierdie tesis.
Die raamwerk vir analise sal deur Flyvbjerg, Bruzelius en Rothengatter (2003) verskaf word, waar die outeurs poog om megaprojekte se sukses of mislukking te bepaal gebaseer op die sleutel aanwysers van ekonomiese volhoubaarheid, omgewingskwessies en die effek van openbare ondersteuning. Hierdie tesis sal gebruik maak van die ekonomiese volhoubaarheid en openbare ondersteuning aanwysers om te bepaal of die GFIP beskou kan word as a mislukte megaprojek of nie.
Na ‘n in-diepte study van die data en materiaal beskikbaar, sal hierdie beskrywende en verduidelikende studie wys dat die GFIP en verwante e-toll megaprojek inderdaad ‘n mislukte megaprojek is, as gevolg daarvan dat die GFIP megaprojek analise aandui dat die megaprojek misluk het in beide die ekonomiese volhoubaarheid en publieke ondersteunings aanwysers.
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Development of pavement management systems for road network maintenanceMapikitla, David January 2011 (has links)
Thesis. (M. Tech. (Faculty of Engineering and Technology, Dept. of Civil Engineering))--Vaal University of Technology, 2011 / In the past thirty years there has been a rapid deterioration of the road network in South Africa. As an attempt to address this challenge, a study was conducted on R34 between Vrede and Bothmas Pass Border. The aim of the study was to develop a pavement management system for road network maintenance to serve as a decision support tool to assist to improve the efficiency of making decisions, provide feedback as to the consequences of these decisions, ensure consistency of decisions made at different levels and improve the effectiveness of all decisions in terms of efficiency of results.
The study focused on developing and testing pavement management system for road network maintenance. Consequently, visual condition inspections, non-destructive and semi-destructive tests were conducted on the field, data acquired, processed and analysed in accordance with guidelines stipulated in the Draft Technical Recommendations for Highways (TRH) 22 in order to draw conclusions.
The data acquired included the surfacing assessments, structural assessments, functional assessments, traffic surveys, riding quality, falling weight deflectometer, mechanical rutting, material investigations and dynamic cone penetration.
After analysis of the data, visual condition index was then calculated to be 40%. Visual condition index was then used to determine the action required towards rehabilitating the road. After consultation with guidelines contained in the TRH22, it was concluded that the pavement treatment needed for the road was Rehabilitation.
It was then concluded that PMS developed would provide key performance indicators to assist with decision support system and that it is also suitable for road network applications ranging from national roads, provincial roads, regional or district arterial and collector / distributor networks in SA.
The municipalities and other road maintenance agencies were then recommended to utilise the “easy to use” developed pavement management system as a decision support tool in their maintenance programmes.
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Dynamic characterization and forensic investigation of reinforced asphalt pavement cores from SR15/US98Unknown Date (has links)
Due to the presence of deep deposits of organic soils at shallow depths, roadways in western Palm Beach County, FL show premature distress and failure requiring frequent rehabilitation. In an effort to develop effective mitigation strategies, 24 test sections, containing various types of pavement reinforcing materials, were constructed during Fall of 2008. This study presents a forensic investigation and dynamic characterization of reinforced asphalt cores obtained from SR15/US98 for evaluating the uniformity of test sections, qualitative comparisons, and developing empirical models for predicting permanent deformation and material damage with stress cycles simulating traffic loading. / by Rodrigo Ledezma-Campodonico. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Comparative analysis between the diverging diamond interchange and partial cloverleaf interchange using microsimulation modelingUnknown Date (has links)
In the last decades, population growth has been outpacing transportation infrastructure growth, and today's transportation professionals are challenged to meet the mobility needs of an increasing population. The effectiveness of the transportation system is an essential constituent of people's daily lives as they commute between different points of interest. Studies show that at many highway junctions, congestion continues to worsen, and drivers are experiencing greater delays and higher risk exposures. Engineers have very little resources to handle this increase in population. One solution to resolve and alleviate congestion due to increasing traffic volumes and travel demands relies in implementing alternative designs. This approach will help traffic engineers determine which design will be the most appropriate for a particular location. This study compares and evaluates the Diverging Diamond Interchange (DDI), which is an unconventional design, to Partial Cloverleaf (ParClo) types A4 and B4 interchange designs by evaluating different Measure of Effectiveness (MOEs). Using microsimulation platform AIMSUN, each interchange type was evaluated for low, medium and high traffic flows. The analysis revealed that the DDI with four through lanes performed better than the ParClo A4 for unbalanced conditions, the DDI with six though lanes had similar results as the ParClo B4 for very high volumes. In terms of queue, the DDI design had a much better performance. The results from the analysis help in providing guidelines to the decision makers for selecting the best alternative in terms of performance. / by Borja Galletebeitia. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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A framework for computer-based cost evaluation of highway projects in developing countries.Fay, Jean-Michel January 1976 (has links)
Thesis. 1976. M.S.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / Microfiche copy available in Archives and Dewey. / Bibliography: leaves 135-138. / M.S.
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Terrain disturbances by winter roads in the lower and central Mackenzie River Valley, N.W.T., CanadaGnieser, Christoph 01 January 1990 (has links)
Winter roads, built from compacted snow and I or ice, are common throughout the circumpolar North. They are considered effective and economical means of providing seasonal access into permafrost terrain while minimizing the potential for environmental damage.
The purpose of this study is an appraisal of long-term environmental impacts of winter roads by comparative assessment of terrain morphology, microclimate, permafrost, soils, and vegetation, on winter road right-of-ways and in adjacent undisturbed control areas.
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Safe Streets, Livable Streets: A Positive Approach to Urban Roadside DesignDumbaugh, Eric 08 August 2005 (has links)
Transportation safety is a highly contentious issue in the design of cities and communities. To enhance community livability, urban designers, architects and city planners often encourage the placement of street trees, aesthetic street lights, and other roadside features in a buffer zone between the pedestrian realm and the vehicle travelway. While such designs clearly enhance the aesthetic quality of a roadway, conventional geometric design practice regards roadside features located in the clear zone as fixed-object hazards, and strongly discourages their use. This study examines roadside safety in urban environments to better understand the nature of urban fixed-object crashes, as well as the safety impacts of livable streetscape treatments.
While the prevailing assumption is that livable street treatments have a negative impact on a roadways safety performance, the existing empirical evidence indicates that such designs are much safer than more conventional roadside designs. Current safety objections to the use of livable street treatments are not based on empirical evidence, but are instead the result of a design philosophy that systematically overlooks the real-world operating behavior of road users.
This study details the origin and evolution of this philosophy, termed passive safety, and subjects it to an empirical test to evaluate its applicability to urban arterial roadways. It finds that passive safety assumptions do not meaningfully explain empirical observations of crash frequency and severity. To enhance contemporary geometric design practice, this study then proceeds to more thoroughly examine the nature and characteristics of urban roadside crashes, and proposes a new design approach, termed positive design that better addresses the twin goals of safety and livability.
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