This paper explores land-use and other considerations in planning for high-speed ground transportation (HSGT) systems in the United States. Beyond the critical issue of project financing, upon which all HSGT projects proposed to date in the United States have foundered, effective corridor planning (including route alignment and station siting decisions) will be key to the successful implementation of future HSGT project proposals in this country. The corridor planning process must consider many variable factors in deciding issues such as station locations, track/guideway routing and construction type, and overall route alignments. Additionally, there are many institutional factors, including community and environmental considerations as well as political and economic issues, which influence route selection and station location decisions. The general planning framework used throughout the United States (shaped, in large part, by federal regulations) is discussed, and comparisons are made with high-speed rail development in other countries, particularly the larger transportation policy issues that have enabled HSGT development elsewhere.

The National Maglev Initiative (NMI) resulted in four distinctly different concepts. The structural systems of the concepts varied greatly, but in general were very complex. This paper evaluates the concepts as to their performance of selected criteria: constructability, reliability, maintainability, adaptability, and durability. Three of the systems used precast, prestressed concrete for the main load-carrying element. One system used aluminum. Only one system, system concept design (SCD-1) could be readily produced in existing precasting plants. None of the systems provided for easy adjustment of operating elements after construction. These systems require construction tolerances that are much more restrictive than conventional practice. Among the stated goals of the NMI concepts were: (1) it should anticipate upgrade; (2) it should be economically and financially attractive; and (3) it should be robust in terms of its susceptibility to adverse weather and its requirement for maintenance. This paper concludes that none of the four concepts adequately met these goals. However, some concepts could achieve the desired goals by relatively modest redesign.

Maglev systems represent an entirely new concept in transportation. They will not operate on nor share the right-of-way with any other system. It is important, therefore, that the guideways be designed and constructed so as to be economical, constructable, durable, adaptable, reliable, and readily maintained. Comparisons should be made with the current transportation systems, especially highways and railroads. Since most of the guideway will be elevated, the comparison should be with the bridges. The object of the comparisons should be to avoid the shortcomings of the other systems while building on their strengths. This paper develops in some detail design and construction criteria that will ensure a good, long-lived performance of the maglev guideway. The importance of beauty should have a low priority in comparison to the other design criteria. Clean, simple details meeting other criteria will ensure an acceptable appearance. These criteria were used in evaluating the four maglev concepts developed for the National Maglev Initiative.

This paper reports results from guideway analyses conducted as part of the National Maglev Initiative (NMI), a government-industry effort from 1989 to 1994, formed to encourage the development of U.S. maglev technology and to assess its potential application within the U.S. transportation system. Covered here are some key guideway design issues that were common to the designs assessed for the NMI, and to maglev guideways in general. They represent aspects that will need additional attention in future efforts to produce structurally sound and economical maglev guideways. These recommendations come from the analyses conducted by a team from the U.S. Army Construction Engineering Research Laboratories, the Civil Engineering Department of the University of Illinois, and Alfred Benesch and Company. The recommendations focus on design philosophy and the development of general design criteria, guideway maintenance and the provision for future alignment adjustment in both the guideway and the magnets, foundation design, and the long-term performance of guideway materials and reinforcement. Generally, one of the main challenges to guideway designers is to produce a structure that will be easily maintainable to the narrow tolerances and precise alignment required for practical high-speed maglev operation.

Conventional reinforced concrete designs will have to be altered when designing a guideway for a maglev using an electrodynamically suspended (EDS) propulsion system. This type of propulsion system generates large magnetic fields that will develop magnetically induced, circulating eddy currents in any conventional steel reinforcement in close proximity to the magnets. These eddy currents, if large enough, may produce significant power losses that could adversely effect operation of the system. This paper presents a method and explanation for civil engineers to use for estimating the power losses due to the presence of metallic reinforcement. This procedure may be used to help guide future designs in the selection and placement of reinforcing material.

A summary of construction cost and scheduling information is presented for four maglev guideway designs on an example route from Baltimore, MD to Newark, N.J. This work results from the National Maglev Initiative (NMI), a government-industry effort from 1989 to 1994. The system design concepts used as a basis for developing cost and construction scheduling information, were submitted by four industry consortia solely for this analysis, and represent their own unpublished designs. The detailed cost and construction schedule analyses cover the main guideway only. A summary estimate was made for stations, power distribution systems, maintenance facilities, and other types of infrastructure. The results of the analyses indicate a number of design aspects which must receive further consideration by future designers. These aspects will affect the practical and economic construction and long-term maintenance of a high-speed maglev guideway.

Under the current economic climate it is expected that any new high-speed rail line in the United States would be constructed as a public/private partnership, requiring substantial private investment, and thus the expectation of reasonable profits. To date, proposed high-speed rail lines have failed to attract sufficient investment to create any new starts, in great part due to the conclusion that these systems would not likely cover their capital and operating costs and also provide reasonable profit for investors. Studies of the economic potential of U.S. high-speed rail lines have commonly considered them as passenger carriers only, depending solely on ridership as a source of revenue. Yet it is likely that significant revenue potential exists for carrying higher value freight as well—perhaps enough to substantially improve the economic viability of certain high-speed operations. Some basic technical aspects of carrying freight on high-speed rail lines are presented, along with an analysis to estimate the quantity of freight that may be technically practical, and thus potentially economically viable, for a high-speed train to carry.

The analysis of a crosstie railroad track in the lateral plane has traditionally been based on the theory of a beam on an elastic foundation, in which the bending rigidity of the track structure is assumed to be twice the rigidity of a single rail, and the ballast resistance is represented by a linear Winkler foundation with modulus k. The traditional analysis ignores the contribution of the ties and rail-tie fasteners to the bending stiffness of the track and the nonlinearity of the ballast resistance. In the present paper the analysis of an infinitely long crosstie track subject to a concentrated lateral load is presented. The analysis is based on the new track equations derived by Kerr and Zarembski in 1981. These equations explicitly account for the contribution of the rails, ties, and fasteners to the bending stiffness of the track. A bilinear approximation is assumed in modeling the lateral resistance due to the ballast. A closed form solution for the track deflection is obtained using the new equations, for displacements in the linear regime. A closed-form solution is obtained for the nonlinear response, using a simplified set of track equations. A method for determining the model track parameters is presented that is based on a least-squares fit to experimental load-deflection data. Results show that the analytical solution accurately predicts the measured data, for the full range of loads and over the entire length of the track.

Many recent intelligent transportation systems (ITS) deployments feature vehicle probes as prominent sources of information about traffic conditions in addition to, or in place of, fixed-location measurement devices such as inductive loop detectors. Several other technologies now used for traffic surveillance and deployed in fixed locations are reviewed and found to provide the same kinds of information as more complex probe vehicle systems. Recent experience with both fixed location and vehicle-based incident detection systems is summarized. Several incident detection algorithms calibrated with both fixed-location and vehicle-based traffic measurements from a simulation of a signalized arterial street are introduced. The performance of these algorithms, some of which use data from only one source while others use data from both sources, is compared. While the fixed-location measurements appear to be superior to the probe reports for detecting incidents when used alone, different incidents are detected by their respective algorithms. Algorithms using both sources of data perform substantially better than either single-source algorithm, indicating that there is value in collecting information using both methods.

Accurate estimates of demand are critical for planning, designing, and operating public transit systems. Previous research has demonstrated that the expected demand in rural areas is a function of both demographic and transit system variables. Numerous models have been proposed to describe the relationship between the aforementioned variables. However, most of them are site specific and their validity over time and space is not reported or perhaps has not been tested. Moreover, input variables in some cases are extremely difficult to quantify. In this article, the estimation of demand using the generalized linear modeling technique is discussed. Two separate models, one for fixed-route and another for demand-responsive services, are presented. These models, calibrated with data from systems in nine different states, are used to demonstrate the appropriateness and validity of generalized linear models compared to the regression models. They explain over 70% of the variation in expected demand for fixed-route services and 60% of the variation in expected demand for demand-responsive services. It was found that the models are spatially transferable and that data for calibration are easily obtainable.

An effective public transportation management system (PTMS) requires accurate and efficient models for the prediction of rolling-stock conditions. If the state of any given rolling-stock unit is known, its future condition can be predicted from the corresponding deterioration curves. The purpose of this study was twofold: first, to evaluate and model the relative importance of factors causing deterioration of rolling stock and, second, to provide projections of future condition to be used in transit capital programming. A methodology was developed for the estimation of rolling-stock deterioration models from condition rating data. Using a rolling-stock inspection data set from Indiana, the capabilities of the proposed methodology are empirically demonstrated. This ordered probit-based methodology provides models that are intuitively appealing, fundamentally sound, and a useful and easy-to-use tool in projecting future rolling-stock condition. The models presented in this paper are a part of the public transit management system being developed in Indiana for determining optimal rolling-stock maintenance, repair, and replacement strategies.

In a densely built-up urban society, operators of public bus services are faced with the recurrent problem of providing timely and reliable service. While they have no control over dynamically changing extraneous factors (such as passenger loads or road conditions) that may suddenly degrade the quality of the service provided, it is nonetheless desirable for management to study the extent to which these factors affect their business, and what measures, if any, can be adopted to neutralize them. This paper discusses how a simulation model of a bus route, embellished by a neural network, was created to model the historical pattern of the inputs (namely, passenger loads and road conditions) that affect the overall scheduled terminus-to-terminus time. Thus, in a case study of a bus route running from a suburb to the city center, it was found that the neurosimulation model could predict the cumulative terminus-to-terminus times better than a conventional simulation model could. A software module, embedded into the neurosimulation model for the purposes of speed regulation, was able to minimize the deviation of the bus service from schedule. When intentional delays were further introduced into the bus route, it was discovered that the speed regulator was more effective the longer the delay, and the further the bus traveled into the bus route. There is potential in applying neural computing in a dynamic bus scheduling problem such as the one discussed here.

Estimation of parking generation of a proposed development is important in facility planning and traffic impact assessment. Studies of parking generation of various land uses have been conducted by many researchers in western countries but few for Asian conditions. In many cases, parking requirements of proposed developments in Asian cities are determined using rates developed for western cities. This may not be appropriate because there are differences in levels of vehicle ownership, public transport service, and traffic management as well as land-use planning. Such differences can result in poorly planned facilities. This paper reports the development of parking generation rates of commercial developments in Singapore. The study found that parking rates depend on the available floor area of the site and whether the site is well served by public transport. The estimated rates for Singapore are about one-quarter to one-third of those reported for similar developments in western cities. An evaluation of two methods of estimating parking generation rates indicated that the regression method provides better estimates.