查看更多>>摘要：Over the past decades, bimodal operation of conventional rail lines—the use of a rail line to carry both passengers and goods—has been studied and put into practice in railway engineering and planning efforts. However, the growing construction of high-speed rail lines in Europe has sparked serious controversy about the possibility of introducing bimodal services on this type of track. This controversy encompasses not only technical issue but also acceptability and economic issues. So far, little has been published about it Bimodal use of high-speed rail lines is now practically nonexistent in Europe, and national governments do not have the necessary information on the feasibility of the system. The first Spanish high-speed railway started to run in April 1992 between Madrid and Seville and, until now, has been used to transport only passengers. The future Spanish high-speed network will be centered in Madrid and will cover more than 2,000 km over the next 15 years. Its operation with bimodal criteria is starting to be discussed as a way to reap maximum benefit from the high investment costs. This paper presents and analyzes the results of the first study on the acceptability of and the potential demand for bimodal use of a Spanish high-speed rail line. The term "acceptability" is used to describe the prospective judgment of measures to be introduced in the future. The target group for the study was a sample of users of the corridor of this high-speed rail lines. As part of the study, more than 3,000 valid questionnaires were collected, and more than 50 companies interviewed.
查看更多>>摘要：The opening of railroad infrastructure to new transport operators in Europe has made it necessary to develop a pricing system for its use. The European Union (EU) has proposed guidelines for establishing a similar pricing system for all EU members. Nonetheless, pricing systems continue to differ substantially from one country to another. These differences reduce continuity between networks and distort the competitive conditions between countries and negatively affect domestic trade. This paper analyzes the pricing systems of eight European countries and presents several proposals for harmonizing them.
查看更多>>摘要：Korean Train Express (KTX) of South Korea introduced high-speed commercial rail service on April 1, 2004. It currently has two lines covering 661.1 km (413.2 mi), and its trains achieve speeds of 300 km/h (186 mph). KTX's offering represents the first phase of a scheduled two-phase introduction due to be completed in 2010. This paper documents the service changes of external transportation operators during the first 3 months of KTX operation and details the initial reactions of KTX customers. KTX reduced rail travel time between major cities by almost half. By offering 128 daily services, it increased seat supply by 33% among the major cities and increased revenue by nearly 100% for the Seoul-Busan line, as compared with the same April-June period the previous year. KTX achieved one million passengers in 14 days and 10 million passengers in 142 days of operation. Although these numbers are significant, they represent only about half the demand forecasted. Three major causes of this discrepancy are an inability to provide fully implemented KTX services, low Korean economic activity, and a degraded level of service on conventional passenger rail systems. The expected service level of passengers and the initial marketing strategies used appear to have negatively affected the successful introduction of KTX. However, demand trends show continued increases after the initial response. As a whole, KTX strengthened the viability of Korean rail travel and is expected to contribute to the building of a more balanced national transportation system.
查看更多>>摘要：In 2005 the Central Japan Railway Company introduced new technological breakthroughs that will enhance revenue service on its superconducting magnetic limitation (maglev) system. This paper covers developments in both basic and applied research, discusses new equipment, and reviews the status of the system's running tests. Superconducting maglev has been developed to be applied to the Chuo Shinkansen, a proposed artery between Tokyo and Osaka. Its basic performance and various functions were already confirmed by 2000 through running tests done on the Yamanashi Maglev Test Line; running tests continue to be conducted to verify the train's durability and reliability and to upgrade its performance with new technologies. One immediate goal of these tests is to finalize the technology necessary for revenue service by March 2005.
查看更多>>摘要：The Railway Technical Research Institute has developed a position detection system based on a new Global Positioning System (GPS). This system uses GPS to detect the approximate location of a train and then selects one of three algorithms to process the location data and determine the train's precise location. Running tests performed on the system showed that its position error was less than 4 m. This system has the potential to be used to control the car body tilting of tilt trains accurately and allow them to run at the maximum possible speed through the tight curves typical of the narrow-gage lines found in Japan. In addition, the automatic map created by this system makes it much easier to maintain the accuracy of the on-board database.
查看更多>>摘要：In North America, the process for determining appropriate railroad infrastructure for new service or an increased volume of existing service usually includes the use of simulation software. Decisions are generally based on statistical analysis of the simulation output. The simulation and analysis that are commonly conducted, however, may not provide an accurate assessment of the adequacy of the infrastructure. Furthermore, the output data comparisons commonly used to describe the effect of infrastructure on traffic may not be easily associated with traffic conditions. These shortcomings can be mitigated with appropriate care in developing the simulation input data and changing the output analysis methodology.
查看更多>>摘要：Wireless technologies have expanded greatly over the past few years as a result of numerous technological advances and regulatory changes. Although rail and urban transit operators have long used radio systems primarily for voice communications, they are increasingly deploying new wireless networks in support of advanced applications for themselves and their customers. These applications have the potential to streamline rail and transit operations, enhance customers' travel experience, and act as a new source of revenue. This paper reviews the recent technological advances and regulatory changes that have encouraged the proliferation of mobile wireless devices and networks and examines the issues associated with their design and deployment in the rail and urban transit environment.
查看更多>>摘要：Intermodal trains are typically the fastest trains operated by North American freight railroads. Ironically, these trains tend to have the poorest aerodynamic characteristics. Because of constraints imposed by equipment design and diversity, intermodal trains incur greater aerodynamic penalties and increased fuel consumption than other trains. Improving the loading patterns of intermodal trains has the potential to improve aerodynamic characteristics and thus fuel efficiency. Train aerodynamics and resistance analyses were conducted on several alternative intermodal train-loading configurations. Matching intermodal loads with cars of an appropriate length reduces the gap length between loads and thereby improves airflow. Filling empty slots with empty containers or trailers also reduces aerodynamic resistance and improves energy efficiency, despite the additional weight penalty and consequent increase in bearing and rolling resistance. Depending on the particular train configuration, train resistance can be lowered by as much as 27% and fuel savings by 1 gal/mi per train.
查看更多>>摘要：Maintaining high, stable rail neutral temperatures helps prevent the buckling of continuous welded rail (CWR) track. Rail neutral temperatures are typically set high during installation (90℉ to 11℉), but the large variations that develop during revenue service often lead to buckling-prone conditions. Readjusting or correcting for these variations requires CWR to be destressed with the use of procedures that do not always restore the desired target neutral temperature. As part of the Federal Railroad Administration's Track Systems Research program, the U.S. Department of Transportation's Volpe Center is investigating rail force and neutral temperature influences on track buckling. An analytic model for field applications has been developed to improve destressing and readjustment of CWR in both winter and summer conditions. The model has been validated in several field tests on instrumented CWR test segments under both high tensile and compressive force conditions. Both wood and concrete tie tracks were tested, and the rail longitudinal movement, rail gap, rail force distributions after rail cutting and welding, and readjusted neutral temperature were measured and correlated with the model predictions. The model and test results were used to develop a field tool for more effective destressing and readjustment of CWR. The tool provides the required removal lengths of anchors/fasteners, the rail gap size requirements when mechanical loads (rail-pullers) are used to adjust to the desired neutral temperature, and the required amounts of steel removal in summer when cutting rail out for stress relief.
Francesco Lanza di ScaleaIvan BartoliPiervincenzo RizzoMahmood Fateh...
p.66-77页
查看更多>>摘要：Recent train accidents have reaffirmed the need to develop rail defect detection systems that are more effective than those used today. This paper proposes new inspection systems for detecting transverse-type cracks in the rail head, notoriously the most dangerous flaws in rails. In principle these systems can be applied to both continuous welded rail and jointed tracks because bidirectional inspection can be implemented. However, the systems may fail to detect defects located close to a joint. The proposed technology uses ultrasonic guided waves that are detected by remote sensors positioned as far away as 76 mm (3 in.) from the top of the rail head. An impulse hammer is used to generate waves below 50 kHz that can successfully detect cracks larger than 15% of the head cross-sectional area. For smaller cracks—those as shallow as 1 mm—a pulsed laser is used for generating waves above 100 kHz. The inspection ranges are at least 10 m (32 ft) for cracks larger than 15% of the head area and at least 500 mm (20 in.) for surface head cracks as shallow as 1 mm. The defect detection reliability is improved by using both reflection and transmission measurements.
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