Transportation Research E-Circular 

About: Transportation Research E-Circular is an academic journal. The journal publishes majorly in the area(s): Road Weather Information System & Decision support system. Over the lifetime, 131 publications have been published receiving 553 citations.

Life-cycle management of concrete infrastructures for improved sustainability

Abstract: The LIFECON Life-Cycle Management System (LMS) is a European model of a predictive and integrated LMS for concrete infrastructures. It is generic in nature and will be suitable for different categories of structures, from buildings, bridges, and nuclear power plants, to lighthouses. LIFECON LMS has two planning phases: long term and short term. The system is also divided into three levels of structural hierarchy: component and module, object, and network. The component- and module-level system addresses structural components such as beams and columns and their combinations in modules. The object-level system deals with complete structures or buildings. The network-level system treats networks of objects such as stocks of bridges or buildings. The LIFECON LMS is capable of considering the many requirements and aims involved in decision making. Besides a structure's observed condition and evaluated urgency of repair, many other requirements should be taken into account, such as life-cycle costs, user costs, minimum requirements of structural performance, structural risks, traffic and other operational requirements, aesthetics, environmental risks, and ecological pressures. Thus, the method of multiple-attribute planning is applied on all hierarchical levels of the system. The life-cycle analysis and optimization module involves the data applications for studying the economy of the life cycle and cost-effectiveness of optional maintenance, repair, and rehabilitation strategies. Alternative strategies are compared as life-cycle activity profiles over a defined time frame. The purpose of life-cycle analyses is to find the optimal activity profiles to reach the targets.

Implementation of new sanding method in norway

Abstract: One of the main achievements in the Winter Friction Project in Norway has been the development of a new sanding method based on a mix of hot water and sand. The most significant factors in this method are the sand quality, the amount of water, the spreading speed, and the water temperature. The sand should be of a specified quality corresponding to a 0 to 4-mm gradation. Hot water means that the water temperature is 90 deg C to 95 deg C. The amount of water in the mixture of sand and water is approximately 30-weight percentage, and the normal dosage of sand used is equivalent to 200 g/sq m as an average. Scientific studies have revealed that measures carried out with the new sanding method last longer than traditional sanding methods. It has been proved that by adding warm water to the sand it is easy to maintain a friction level above the standard even after the passage of 2,000 vehicles. Under favorable road and weather conditions, satisfactory friction values have been maintained for up to 3 to 7 days on roads with annual average daily traffic of 1,500 vehicles. The introduction of wet gritting means substantial improvement, both in regard to friction and in time of effect. The new method is expected to have a marked impact on winter road operations. In Norway there are now a total of approximately 30 trucks based on the new sanding method, and the method is being used on national roads, in municipalities, and on air fields.

Statewide Travel Demand Modeling: A Peer Exchange, Longboat Key, Florida, September 23-24, 2004

Abstract: The Transportation Research Board Committee on Statewide Multimodal Transportation Planning (ADA10) and the Federal Highway Administration sponsored a national Statewide Travel Demand Modeling Peer Exchange in Longboat Key, Florida, September 23-24, 2004. The states represented in the peer exchange had a wide range of experiences with statewide travel demand models (TDMs)--some had never considered a model, some were debating the development of a model, some had attempted to develop a model with limited success, and others were actively using a model in many aspects of state planning and operation. The participants discussed their statewide models (if they had one), the purpose and use of models in their state, problems and limitations of the model, and plans for future improvements. This document was assembled from responses submitted by the various participants. Most of the responses were received from state departments of transportation and this document focuses on a presentation and comparison of the modeling efforts in these various states. This comparison is not meant to be all inclusive as a number of states with important statewide modeling efforts are not included either due to their own inability to participate or the constraint on the number of participants. The report is organized as follows. Section 1 is an introduction. Section 2 summarizes the participants' responses regarding the status of their statewide modeling efforts. The states are listed alphabetically and each follows a standard format beginning with a general description followed by information related to seven topic areas: data requirements, maintenance/use, implementation, scale/level of detail, statewide/urban model integration, freight/commercial vehicle modeling, and long-distance/recreational/tourism travel. Section 3 provides a tabular comparison of various specific features of the statewide models. Section 4 contains a summary of the discussion held during the Statewide Model Peer Exchange. Section 5 provides a discussion on the ranking of future research efforts and includes four statements on the four highest ranked research needs identified by the participants. The report contains three appendices. Appendix A is the agenda for the peer exchange, Appendix B is the detailed questionnaire responses of participants, and Appendix C is a list of acronyms.

Ridership trends of new start rail projects

Abstract: This paper reports on the ridership trends of new start light rail transit (LRT) projects implemented in the last two decades. These systems are colloquially referred to as "new start" systems. The purpose of the research presented here is to look at the process of maturation of these systems in terms of ridership trends. Each system's ridership is examined, and system extent in terms of route miles and service miles also are examined. The research attempts to discern the impact of service expansion associated with the system synergies that might result from increased accessibility, through the review of ridership changes as LRT systems grow in contrast to service supply. This review of the National Transit Database data indicates that ridership trends for new start LRT projects matured relatively quickly, with subsequent growth driven by system extent and service levels. The initial rapid maturation is partially attributable to the high levels of attention light rail lines receive when they are under development and implemented, as well as the inherent physical presence that LRT provides for transit. It is interesting to note that the LRT systems, even the more mature systems, are a modest share of the urban area's total transit service, with the most successful systems providing approximately 30% of total regional transit trips. LRT investments may be very important to a community by stimulating attention and investment in public transit. LRT implementation has helped several communities expand public transit use; however, it has not resulted in dramatic changes in the role that public transit plays in regional mobility in the respective communities. While LRT is playing an important role in expanding opportunities for transit use, even LRT system development is a lengthy process with no assurance of substantial increases in transit ridership.

Laboratory melting performance comparison: rock salt with and without prewetting

Abstract: Prewetting road salt with liquid deicing chemicals has been suggested as a way to improve the melting performance of the salt and potentially reduce the amount of salt required to clear a roadway. Forensic Dynamics Inc. undertook this research to explore these possibilities. A protocol for manufacturing repeatable compact snow and for trafficking this snow to simulate rolling tire compaction was developed following a literature review and experimentation. ASTM Standard D632-83 rock salt was prewetted with a liquid deicing chemical and applied to compact snow. The friction of a rubber tire on this sample was measured and provided friction versus time curves for dry rock salt and each of six prewetted salt mixtures. Tests were conducted at 4, 8, and 12 gal of liquid chemical per ton of rock salt, and at -1 deg C, -5 deg C, and -10 deg C. Three application rates were tested for most chemicals. Prewetting salt slightly decreased its performance at -1 deg C and -5 deg C. However, all of the prewetted mixtures were effective at -10 deg C, unlike the dry rock salt. Melting was improved by increasing the ratio of liquid deicer to rock salt. Some mixtures had considerable variation in melting performance with temperature, but others remained quite consistent. Attempts to use reduced amounts of prewetted salts to achieve the same performance as a greater amount of dry rock salt gave unexpected results. Specifically some mixtures performed better when less of them were applied at -1 deg C and -5 deg C. No explanation for this was found.