The paper aims to provide an overview of the key factors to consider when performing reliable modelling of rail services. Given our underlying belief that to build a robust simulation environment a rail service cannot be considered an isolated system, also the connected systems, which influence and, in turn, are influenced by such services, must be properly modelled. For this purpose, an extensive overview of the rail simulation and optimisation models proposed in the literature is first provided. Rail simulation models are classified according to the level of detail implemented (microscopic, mesoscopic and macroscopic), the variables involved (deterministic and stochastic) and the processing techniques adopted (synchronous and asynchronous). By contrast, within rail optimisation models, both planning (timetabling) and management (rescheduling) phases are discussed. The main issues concerning the interaction of rail services with travel demand flows and the energy domain are also described. Finally, in an attempt to provide a comprehensive framework an overview of the main metaheuristic resolution techniques used in the planning and management phases is shown.
A light rail passenger transportation system is being built in Seattle, WA, USA, that traverses Lake Washington over an existing pontoon bridge. The water level in Lake Washington changes throughout the year. This causes rotations of the transition spans, which are needed at each end of the bridge to carry traffic between the fixed, land-based structure, and the floating structure. This paper explains a novel method, the Curved Element Supported Rail (CESuRa) system, that provides rails with the ability to undergo joint rotations at the ends of the transitions spans without risk of damage, while maintaining full vertical support of the track across the joint. The geometric characteristics on which it depends for proper operation, considerations that must be accounted for when using the system for other applications in the future, and an overview of the implementation of the system on the floating bridge are discussed.
The objective of this paper is to analyze if there is any difference between the light rail systems in Spain according to whether they have been carried out through public financing or private financing (totally or partially). The importance of this study lies in the fact that, for decades, the public–private partnership has been proposed as an alternative to public financing of public transport projects in order to obtain additional financial resources, reduce the public deficit, and increase efficiency. However, there are hardly any detailed studies describing how these initiatives have turned out. Therefore, the present study analyzes if there is any difference in the main variables explaining the performance of light rail projects in Spain depending on their source of funding can be found. For this, the relationship between variables related to design, operation and costs of the projects, and the percentage of private financing were statistically analyzed. As the most relevant conclusion, we underline the fact that the investment per passenger increases when financing is completely private. This would indicate that the most cost-effective lines, from a social standpoint, were financed totally or partially by the public administrations, whereas the least beneficial ones for society were assigned to private enterprises. This finding provides an advance in the knowledge of the consequences of private participation in the financing of public transport projects, indicating, moreover, that the biggest beneficiaries of this type of projects might be the construction companies and the politicians involved.
Although the accident number involving trams is comparatively very limited to the total road accident number, the consequences of tram crashes are very serious, especially when pedestrians are run over. The new power supply technologies (e.g. catenary-free systems) allow to build tram networks, even in old town centres and pedestrian areas, with additional increased risk of pedestrian casualties. This will require specific design solutions and traffic regulations for road safety as described in this paper, with particular regard to vulnerable users (i.e. pedestrians and cyclists), especially near intersections and pedestrian crossings. Therefore, the research analyses the road accident rate and its evolution in the last 10 years with specific focus on Italian tramways. The main risk conditions and the strategies used worldwide to improve the safety of tramway system in the urban context are described. The main countermeasures to reduce accident risks are aimed at better warning road users of specific risk conditions. Other countermeasures are designed to install suitable facilities on road platforms for better informing users of tramway system, for limiting or temporarily prohibiting turning movements or manoeuvrings and for properly channelling pedestrian and vehicle flows with the purpose to avoid or reduce interference with trams.
Access to good public transit for low-socioeconomic communities has been an important concern in transportation planning and urban studies research. In Portland, Oregon, USA, the rapid growth of housing prices and rents in the urban core has caused displacement of low-income residents to peripheral and suburban neighborhoods where housing is more affordable. Because public transit is generally more limited in the urban periphery and suburbs, there is concern that the low-income suburban residents may have more limited access to Portland’s light rail transit service than more affluent residents do. This study examines the relationships between the light rail transit accessibility and socioeconomic status—income, race and ethnicity—in the Portland metro area. Light rail transit accessibility is compared for all income and racial/ethnic groups across four access zones. Multinomial logistic econometric models were used to measure likelihood differences of being located in different access zones between each demographic group. The results show that there is no significant barrier for low-income and racial and ethnic minority residents to access urban rail transit in Portland. The results suggest that despite low-income residents’ movement to the suburbs, Portland’s urban rail transit system continues to serve all residents by providing cohesive connections between the urban core, periphery and suburbs.
This paper describes an innovative integration of eye tracking (ET) with virtual reality (VR) and details the application of these combined technologies for the adaptive reuse redesign of the Wudaokou rail station in Beijing. The objective of the research is to develop a hybrid approach, combining ET and VR technologies, as part of an experimental study of how to improve wayfinding and pedestrian movement in crowded environments such as those found in urban subway stations during peak hours. Using ET analysis, design features such as edges, and color contrast are used to evaluate several proposed rail station redesigns. Through VR and screen-based ET, visual attention and related spatial responses are tracked and analyzed for the selected redesign elements. This paper assesses the potential benefits of using ET and VR to assist identification of station design elements that will improve wayfinding and pedestrian movement, and describes how the combination of VR and ET can influence the design process. The research concludes that the combination of VR and ET offers unique advantages for modeling how the design of rail transit hub interiors can influence the visual attention and movement behavior of those using the redesigned station. This is especially true for crowded conditions in complex interior spaces. The use of integrated ET and VR technology is shown to inform innovative design approaches for facilitating improved wayfinding and pedestrian movement within redesigned rail stations.
Under the background of the rapid development of urban rail transit in China, the development demand of urban underground space has also greatly increased especially in the rail transit station areas. In this paper, taking the high-speed railway station area of Xuzhou Metro Line 1 as an example, the underground space development demand evaluation is conducted by considering the principle of urban underground space stock planning, the local underground space development conditions, as well as the special planning of the local urban constructions. Using the Analytic Hierarchy Process (AHP), a specific weight indicator scale is employed after the rationality of different weight indicator scales being compared. And then the weight indicator of different function types, i.e., commercial, parking, road, etc., are calculated and laterly utilized to forecast the recent development demand of underground space in the station area. Moreover, the steps to forecast the underground space development demand in rail transit station area are proposed, which can provide a reference for the forecasting of underground space development demand in the urban rail transit station areas.
This research assesses the appreciation in residential property values in connection with proximity to the Little Miami Scenic Trail, a multi-purpose biking, hiking, and jogging trail built along an abandoned railroad corridor near Cincinnati, Ohio, USA. Applying two spatial hedonic frameworks, the spatial lag of X (SLX) model and the spatial Durbin error model, we conclude that proximity to trail entrances had significant impacts on property values for both, Euclidean and network distance measures. Specifically, the SLX results indicate that decreasing the distance to the closest trail entrance by one foot (meter) increases a house’s property value by US$0.92 (US$3.02) when using network distances.