A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2017 / The principle focus of this research is to provide a novel approach to accident investigation theory by focusing on the investigation process itself as a complex system. A number of systemic factors inherent in this system impact on the effectiveness (accuracy, quality, validity, reliability and objectivity) of railway investigations. There is a need to explore why railway occurrences remain high in South Africa, despite railway Operators investigating occurrences. If occurrences are investigated, why then do the number of events remain unchanged? Ineffective investigations impact on the accuracy of the findings identified and the suitability of the recommendations. Added to this is the failure of implementing recommendations from investigations contributing to the high number of occurrences and repeated occurrences. Complex influencing factors inherent within the railway system influence the actual investigation process and therefore its effectiveness. This is despite interventions put in place by various organisations, industries, and sectors to improve railway safety. A critical review of the literature, in terms of accident investigation theory, indicates that the current research targets various approaches, methods and models to determine why accidents occur; from a human, technical, or system perspective. The literature focusses on accident causation by addressing the system and its role in contributing to such events. However, very little critical analysis exists on the actual investigation process of accidents as a complex system in its own right, and its contributory role in the ongoing high number of accidents. Rasmussen’s (1997) Risk Management Framework is used in this research to illustrate the South African railway system hierarchy. A qualitative mixed methods approach using triangulation was adopted. Methods included a print media analysis of reported railway accidents, document analyses of governance documents, analyses of railway investigation reports, semi-structured interviews with railway investigators and observations of investigation inquiries. Thematic content analysis was conducted to identify the themes emerging from the data. The results indicate that systemic factors influence the manner in which occurrences are investigated. Examples include no National Rail Policy, limited resources to investigate, shortage of skilled investigators, absence of investigator training, non-compliance to governance documents, an underinvestment in rail, financial constraints, and a blame culture. An Accimap summarises the systemic factors impacting on the effectiveness of the accident investigation process, its outcomes and the recurrence of accidents. Conclusions demonstrate that the accident investigation process is indeed an example of a complex system. Systemic factors collectively behave to influence the effectiveness of the investigation process, but also on the bigger rail socio-technical system which impacts on the safety, reliability and efficiency of the South African railway system. The theoretical contribution of this research is identified in the useful and novel application of Rasmussen’s (1997) Risk Management Framework to illustrate that the accident investigation process is an example of a complex system. Adjustments to Rasmussen’s (1997) Risk Management Framework were made in order to contextualize it to the problem of this research, confirming the importance and application of Rasmussen’s work in the system of accident investigations and not only in accident causation. / MT 2018

Uma nova abordagem de sistema de gerência de pavimentos ferroviários é exposta nesta tese. O objetivo principal da pesquisa foi o desenvolvimento de um sistema de gerência em nível de rede e análises do custo do ciclo de vida em nível de projeto, adotando como estudo de caso a Estrada de Ferro Vitória Minas. A revisão bibliográfica apresenta modelos de avaliação da qualidade geométrica e estrutural no Brasil e no mundo. O desenvolvimento iniciou-se com a composição do sistema de gerência em nível de rede utilizando um inventário do trecho em estudo, a subdivisão dessa via em segmentos homogêneos de comprimento variável de acordo com a geometria (curva e tangente), e a aplicação de seis códigos: (i) classe de via; (ii) inventário da estrutura do pavimento com base no tipo de dormente; (iii) geometria com a definição da metodologia de avaliação da qualidade geométrica, propondo um índice que aplica o desvio padrão dos parâmetros geométricos (bitola, empeno, alinhamento e nivelamento transversal), a contagem de exceções e os respectivos limites de alerta, intervenção e segurança; (iv) superfície pela análise do desgaste do trilho e defeitos superficiais; (v) segurança pelo coeficiente de atrito; e (vi) capacidade estrutural com a aplicação do módulo de via parametrizado pelo carro controle. A partir dos seis códigos, foi possível categorizar a estratégia de manutenção aplicável e, em nível de projeto, foram analisadas as degradações do lastro e do desgaste do trilho, com definições de equações de predição, o que permitiu simular o custo do ciclo de vida das estratégias. Por fim, para verificar a viabilidade técnica da estratégia de manutenção apontada, foram estudadas as tensões no topo do lastro e do subleito e ainda o módulo de via por retro análise das deflexões medidas da via permanente em duas seções da EFVM. / A new approach to the railroad track management system is presented in this thesis. The main objective of the research was the development of a network management system and life cycle cost analysis in a project level, adopting as a case study of the Estrada de Ferro Vitoria Minas. The bibliographic review has exposed geometric and structural track quality evaluation models in Brazil and in the world. The development began with the composition of the network management system using an inventory of the track under study, the subdivision of the railway into homogeneous segments of variable lengths depending on the geometry (curve and tangent), and the application of six codes: (i) class, (ii) pavement structure inventory based on tie type, (iii) geometry with definition of quality assessment methodology proposing an index that applies the exception counting and the standard deviation of the parameters - cross level, warp, alignment and gauge - and safety, alarm and intervention limits, (iv) surface by analysis of rail wear and rail surface defects, (v) safety by friction coefficient, and (vi) structural capacity with the application of the track modulus parameterized by the track geometry car. From the six codes, it was possible to categorize the applicable maintenance strategy at a project level, create prediction equations of the ballast and the rail wear degradation and simulate life cycle cost of the strategies. In order to verify the technical feasibility of the mentioned maintenance strategy, it was measured the stress at the top of the ballast and subgrade and the track modulus by retroanalysis deflections in two sections of the EFVM.

Thesis (M. Arch.)--University of Hong Kong, 2001. / Includes special study report entitled: Sensory landscape as urban-nature-space. Includes bibliographical references.

M. Tech. Architecture (Professional) / This dissertation deals with the exploration of turning a distant memory into a functional reality. The project focuses on architecture's potential to connect. The aim of the design proposal is to re-establish the programmatic exchange and confluence of commuters between South Africa and Mozambique on the so-called Eastern Railway Line. The proposed site (Mbombela Train Station) forms a comprehensive construct of history and decay. Currently, the site hosts an almost forgotten domestic train station, numerous unused office buildings and sheds. Established in 1895 as a railhead, it occasioned the development of Nelspruit (now known as Mbombela). The project investigates the typology of the train station: the spatiality and materiality of the current Eastern railway line prompts the architectural response. As a result, heritage incorporates and complements the vernacular (universal) language of the coalesced commuter. The proposed programme explores the threshold between the commuter and the city. The perceived spatial permanence of the platform mediates arrival and departure. An international railway station to act as a gateway between Mbombela and Maputo is thus proposed.

published_or_final_version / Architecture / Master / Master of Architecture

The pressure distribution at the ballast-tie interface of railroad track plays a key role in overall track support. Failure of the ballast or tie can result from excessive loads that were not designed for, requiring increased maintenance and reducing railroad operating efficiency. Understanding the forces acting on the ballast and tie are required to design higher performance and longer lasting track. To further this understanding, the use of Matrix Based Tactile Surface Sensors (MBTSS) is employed to measure the actual pressure distribution at the ballast-tie interface, characterized by individual ballast particle contact points and non-uniform pressures. The research explores this application of MBTSS including the development of sensor protection and calibration procedures. Results from laboratory ballast box testing conducted at the Transportation Technology Center, Inc. (TTCI) are presented. Conservative estimates of peak pressure under a typical wheel load on new ballast averaged 1450 psi and on fouled ballast averaged 680 psi. Contact areas varied across the range of ballast gradations and are shown to increase under increased applied load. A parameter to describe the "roughness" of the ballast-tie pressure distribution is offered. Results from in-track testing performed at TTCI, including pressure distributions along ten test ties, are also presented.

The railroad depot has played an integral role in countless towns and cities throughout the state of Indiana and in other regions of the nation. In many communities, the depot served as the local newsstand, post office, and social gathering place. A community’s railroad depot was a symbol of pride, which was evident by the significant level of architectural detail found in these transportation edifices. Over the course of the past fifty years, a vast majority of these architectural gems have fallen into disrepair, or worse, been demolished because it was believed that the depot could no longer fulfill a viable role in a post-railroad oriented society. There have been multiple efforts to rehabilitate the railroad depot by both the private and public sectors. Although many efforts have been made, there are still numerous historic depots throughout Indiana that are in need of assistance and in danger of being razed. Therefore, this thesis investigates the role of the depot in Indiana towns and cities today by looking at different rehabilitation projects that have successfully saved the railroad depot and transformed it once again into an active member of the local community. / History of the railroad industry in Indiana -- Development of the railroad depot in Indiana -- Literature review on railroad depot rehabilitation -- Methodology for case studies -- Depot rehabilitation case studies -- Conclusion. / Department of Architecture

Thesis (M.Arch.)--University of Hong Kong, 2001. / Includes special study report entitled : Sensory landscape as urban-nature-space. Includes bibliographical references. Also available in print.

Uma nova abordagem de sistema de gerência de pavimentos ferroviários é exposta nesta tese. O objetivo principal da pesquisa foi o desenvolvimento de um sistema de gerência em nível de rede e análises do custo do ciclo de vida em nível de projeto, adotando como estudo de caso a Estrada de Ferro Vitória Minas. A revisão bibliográfica apresenta modelos de avaliação da qualidade geométrica e estrutural no Brasil e no mundo. O desenvolvimento iniciou-se com a composição do sistema de gerência em nível de rede utilizando um inventário do trecho em estudo, a subdivisão dessa via em segmentos homogêneos de comprimento variável de acordo com a geometria (curva e tangente), e a aplicação de seis códigos: (i) classe de via; (ii) inventário da estrutura do pavimento com base no tipo de dormente; (iii) geometria com a definição da metodologia de avaliação da qualidade geométrica, propondo um índice que aplica o desvio padrão dos parâmetros geométricos (bitola, empeno, alinhamento e nivelamento transversal), a contagem de exceções e os respectivos limites de alerta, intervenção e segurança; (iv) superfície pela análise do desgaste do trilho e defeitos superficiais; (v) segurança pelo coeficiente de atrito; e (vi) capacidade estrutural com a aplicação do módulo de via parametrizado pelo carro controle. A partir dos seis códigos, foi possível categorizar a estratégia de manutenção aplicável e, em nível de projeto, foram analisadas as degradações do lastro e do desgaste do trilho, com definições de equações de predição, o que permitiu simular o custo do ciclo de vida das estratégias. Por fim, para verificar a viabilidade técnica da estratégia de manutenção apontada, foram estudadas as tensões no topo do lastro e do subleito e ainda o módulo de via por retro análise das deflexões medidas da via permanente em duas seções da EFVM. / A new approach to the railroad track management system is presented in this thesis. The main objective of the research was the development of a network management system and life cycle cost analysis in a project level, adopting as a case study of the Estrada de Ferro Vitoria Minas. The bibliographic review has exposed geometric and structural track quality evaluation models in Brazil and in the world. The development began with the composition of the network management system using an inventory of the track under study, the subdivision of the railway into homogeneous segments of variable lengths depending on the geometry (curve and tangent), and the application of six codes: (i) class, (ii) pavement structure inventory based on tie type, (iii) geometry with definition of quality assessment methodology proposing an index that applies the exception counting and the standard deviation of the parameters - cross level, warp, alignment and gauge - and safety, alarm and intervention limits, (iv) surface by analysis of rail wear and rail surface defects, (v) safety by friction coefficient, and (vi) structural capacity with the application of the track modulus parameterized by the track geometry car. From the six codes, it was possible to categorize the applicable maintenance strategy at a project level, create prediction equations of the ballast and the rail wear degradation and simulate life cycle cost of the strategies. In order to verify the technical feasibility of the mentioned maintenance strategy, it was measured the stress at the top of the ballast and subgrade and the track modulus by retroanalysis deflections in two sections of the EFVM.

UAVs have gained in popularity and the number of applications has soared over the past years, ranging from leisure to commercial activities. This thesis is discussing specifically railroad applications, which is a domain rarely explored. Two different aspects are analysed. While developing a new application or migrating a ground-based system to UAV platform, the different challenges encountered are often unknown. Therefore, this thesis highlights the most important ones to take into consideration during the development process. From a more technical aspect, the implementation of autonomous guidance for UAVs over railroads using vanishing point extraction is studied. Two different algorithms are presented and compared, the first one is using line extraction method whereas the second uses joint activities of Gabor filters. The results demonstrate that the applied methodologies provide good results and that a significant difference exists between both algorithms in terms of computation time. A second implementation tackling the detection of railway topologies to enable the use on multiple rail road configurations is discussed. A first technique is presented using exclusively vanishing points for the detection, however, the results for complex images are not satisfactory. Therefore, a second method is studied using line characteristics on top of the previous algorithm. This second implementation has proven to give good results.