Nemzetközi szemle: Május
Gyorsított hídépítési módszerek használati lehetősége a hidak rehabilitációjában
Synthesis on the Use of Accelerated Bridge Construction Approaches for Bridge Rehabilitation
Szerző(k): Phares, B., Cronin, M.
Iowa State University, USA
Terjedelem: 74 oldal
Accelerated bridge construction (ABC) has received significant research attention in recent years. For the most part, these research endeavors have focused on means and methods for decreasing impact to the traveling public during new bridge construction. At the same time, great opportunities exist to further reduce traffic impacts by decreasing construction time associated with bridge repair and rehabilitation. Most bridges undergo several small and one or two major rehabilitations during their useful lives and decreasing the traffic impacts during these events could have significant societal benefits. Fortunately, many of the new construction concepts may be able to be adapted for use in rehabilitation scenarios. In still other cases, new means and methods may be needed. This research completes a synthesis of available rehabilitation alternatives and solutions that could be used by practitioners to complete rapid rehabilitation projects. In some cases, these alternatives are adaptations of new construction methods and, in others, they are strictly for rehabilitation activities. This synthesis provides a comprehensive summary of available solutions.
Közlekedési rendszer irányítási és üzemeltetési előnyök értékelése alternatív csomóponti megoldások esetén
Evaluating Transportation Systems Management & Operations (TSM&O) Benefits to Alternative Intersection Treatments
Szerző(k): Abou-Senna, H., Radwan, E., Tabares, S., Wu, J., Chalise, S.
University of Central Florida, USA
Terjedelem: 191 oldal
This research provides a comprehensive review and assessment of current ‘alternative intersection’ methods which successfully eliminate the left-turn phase. With increasing traffic and limited resources, the Florida Department of Transportation moves forward with a vision of optimizing intersection control through the implementation of innovative intersection designs through the Transportation Systems Management & Operations (TSM&O) program. Because of the specific interest in the integration of alternative intersection treatments within the State of Florida, this research assessed the operational benefits, challenges, evaluated the safety implications for bicycles and pedestrians through the alternative intersection methods, and quantified driver confusion opportunities, maintenance impacts, and comparative cost control measures for benefit-to-cost ratio development. The operational analysis is based on several case studies presented along with the advantages and disadvantages of each alternative. The overall analysis provided a variety of parameters that need to be considered when implementing any of these designs. These intersections can be significantly cumbersome for vehicles, bicyclists, and pedestrians to navigate without proper implementation of wayfinding signs and education of the road users. However, when applied properly, the benefits of these designs can save municipalities years of capacity and preserve the existing infrastructure for a longer period of time. These goals align with the overall goal of the FDOT TSM&O program.
A közösségi és a magán mobilitás között – új közlekedési szolgáltatási technológiák vizsgálata
Between Public and Private Mobility – Examining the Rise of Technology-Enabled Transportation Services
Szerző(k): Committee for Review of Innovative Urban Mobility Services
Transportation Research Board, USA
Information and communication technologies, combined with smartphone applications and location data from global positioning systems, are making feasible transportation services that have long been imagined but never realized on a large scale. These innovations include carsharing; bikesharing; microtransit services; and, most notably, transportation network companies (TNCs) such as Uber and Lyft. Although it is too early to draw definitive conclusions, the development of such public policies will require careful analysis of both the potential benefits and risks of evolving and expanding shared mobility services. In particular, the continued expansion of these services has potentially important implications for the location preferences of households and firms, and for their travel patterns generally and their use of public transit specifically in the years ahead. In addition, substantial growth in the concurrent sharing of vehicles could meaningfully contribute to the attainment of resource-efficient and environmentally sustainable lifestyles. The study concludes that innovative mobility services can provide broad mobility benefits while serving other societal goals, but that reaping these benefits will require informed policy making. The committee favors a carefully calibrated regulatory approach for both innovative mobility services and the traditional services with which they frequently compete—an approach that accomplishes public policy goals and creates a level playing field while still allowing the full spectrum of mobility services ample opportunity to innovate and compete.
Városközi vasúti személyszállítás a dinamikus utazási piacon
Intercity Passenger Rail in the Context of Dynamic Travel Markets
Szerző(k): RSG, Inc., Coogan, M., AECOM, Ajzen, I., Bhat, C., Lee, B., Ryerson, M., Schwieterman, J. Transportation Research Board, USA
Terjedelem: 149 oldal
This NCRRP project, Intercity Passenger Rail in the Context of Dynamic Travel Markets, is designed to help practitioners understand the forces influencing the choice of the rail mode; and, once understood, to predict alternative contexts for travel behavior in the future. The overall objective of this research is to develop an analytical framework to improve understanding of how current or potential intercity travelers make the choice to travel by air, rail, bus, or private automobile for the majority of their trip. This framework should provide guidance for use by a diverse audience of practitioners and decision makers considering alternative planning, operating, financing, service, and capital investment strategies for intercity passenger rail service in existing and potential travel markets, and it should allow users to evaluate how mode choice is affected by a variety of changing and evolving parameters. A second objective is to produce this analytical framework on two levels: one that is designed to help the practitioner understand the interaction of key factors in the process of attitude formation toward intercity travel by mode; and a second level in which these relationships are operationalized with methods designed to be ultimately incorporated into the transportation demand forecasting process.
Gépi látás alapú útállapot megfigyelés és értékelés: alakzat alapú burkolat repedés meghatározó módszer fejlesztése
Machine-Vision-Based Roadway Health Monitoring and Assessment: Development of a Shape-Based Pavement-Crack-Detection Approach
Szerző(k): Wang, T., Gopalakrishnan, K., Somani, A., Smadi, O., Ceylan, H.
Iowa State University, USA
Terjedelem: 48 oldal
State highway agencies (SHAs) routinely employ semi-automated and automated image-based methods for network-level pavement-cracking data collection, and there are different types of pavement-cracking data collected by SHAs for reporting and management purposes. The main objective of this proof-of-concept research was to develop a shape-based pavement-crack-detection approach for the reliable detection and classification of cracks from acquired two-dimensional (2D) concrete and asphalt pavement surface images. The developed pavement-crack-detection algorithm consists of four stages: local filtering, maximum component extraction, polynomial fitting of possible crack pixels, and shape metric computation and filtering. After completing the crack-detection process, the width of each crack segment is computed to classify the cracks. In order to verify the developed crack-detection approach, a series of experiments was conducted on real pavement images without and with cracks at different severities. The developed shape-based pavement crack detection algorithm was able to detect cracks at different severities from both asphalt and concrete pavement images. Further, the developed algorithm was able to compute crack widths from the images for crack classification and reporting purposes. Additional research is needed to improve the robustness and accuracy of the developed approach in the presence of anomalies and other surface irregularities.
Nagy felbontású 3D felületi adatok felhasználása a burkolatfelület időbeli változásának megfigyeléséhez.
Use of high-resolution 3-D surface data to monitor change over time on pavement surfaces
Szerző(k): McRobbie, S., Wallbank, C., Nesnas, K., Wright, A. Transport Research Laboratory, UK
Terjedelem: 59 oldal
Surface disintegration is a term used to cover a range of progressive defects such as fretting or ravelling which are caused by aging of binder and loss of adhesion to aggregate. If allowed to progress unchecked surface disintegration can lead to the removal of the wearing course of a pavement, uneven surfaces and potholes. The timescale from the initiation of these defects to the point at which expensive and disruptive maintenance is required can be short, particularly on thin surfacings, which are becoming more prevalent on the Highways Agency network. A fretting algorithm has been developed by TRL and incorporated into TRAffic-speed Condition Surveys (TRACS) which characterises the texture of the surface of a pavement and compares it with the surrounding pavement in order to identify areas which may be deteriorating. This approach works quite well where the fretting is quite well established and distinct from its surroundings, but by the time the TRACS algorithm detects the fretting there may be a very short window for action before the surface disintegration develops into a serious defect such as a pothole. A method which afforded the engineers responsible for maintaining the network more warning of potential deterioration would therefore be desirable. The research presented herein follows two main strands and builds on work previously undertaken by TRL for the Highways Agency. The two strands of work are 1) the development of improved and accurate methods for aligning data from successive surveys, and 2) laboratory testing and investigation into the use of high-resolution 3-D parameters for identifying the onset of surface disintegration at a stage prior to that which can be detected by the existing TRACS fretting algorithms.
Previous research has indicated that development of an absolute measurement of surface disintegration may be very difficult, and would require detailed knowledge of the surface material. Therefore this work has investigated the development of methods for detecting and reporting changes in surface conditions, which may be indicative of surface disintegration. In order to determine whether or not a pavement is changing at a level of detail which would enable the loss of individual chips of aggregate to be detected it is vital that the data from successive surveys can be accurately and reliably aligned such that any changes in the calculated parameters are the result of genuine condition changes and not merely a side-effect of having misaligned the datasets. The work presented in this report describes the alignment methods developed. These use GPS data to perform an initial location of the data, then make use of the longitudinal profiles measured to determine how the surveys should be adjusted longitudinally. This is then followed by use of transverse profiles from successive surveys to refine the alignment and remove the effects of driving line etc. The report describes the development of the methods, and the experimental work performed to validate it against reference data.
USA Nemzeti Közlekedési Statisztika 2015.
National Transportation Statistics 2015
Szerző(k): Bureau of Transportation Statistics, USA
Terjedelem: 470 oldal
Compiled and published by the U.S. Department of Transportation’s Bureau of Transportation Statistics (BTS), National Transportation Statistics presents information on the U.S. transportation system, including its physical components, safety record, economic performance, energy use, and environmental impacts. National Transportation Statistics is a companion document to the Transportation Statistics Annual Report, which analyzes some of the data presented here, and State Transportation Statistics, which presents state level data on many of the same topics presented here.
The report has four chapters: Chapter 1 provides data on the extent, condition, use, and performance of the physical transportation network. Chapter 2 details transportation’s safety record, giving data on accidents, crashes, fatalities, and injuries for each transportation mode and hazardous materials. Chapter 3 focuses on the relationship between transportation and the economy, presenting data on transportation’s contribution to the gross domestic product, employment by industry and occupation, and transportation-related consumer and government expenditures. Chapter 4 presents data on transportation energy use and transportation-related environmental impacts.
Kedvezőbb üzemeltetés a külsőségi állami utakon az utazási idő, az utazási idő megbízhatósága és a téli állapotindex információk felhasználásával
Use of Travel Time, Travel Time Reliability, and Winter Condition Index Information for Improved Operation of Rural Interstates
Szerző(k): Milliken, E., Young, Rh. University of Wyoming, USA
Terjedelem: 92 oldal
Using intelligent transportation systems to help report traveling conditions has been reserved for urban areas. The goal of this research was to help develop a new methodology for incorporating travel times calculated from intelligent transportation system (ITS) technology into Wyoming’s road and weather condition reporting system. Bluetooth sensors and speed sensors were used to measure travel times on I-80 between Cheyenne and Laramie, as well as WY-28 between Farson and Lander in Wyoming. From previous research, the distribution of travel times on I-80 show two distinct modes. Travel times from the WY-28 corridor were then calculated to determine if this trend was common with other rural highways. The next step in this research was to determine the best way to measure travel times on a rural corridor. Bluetooth sensor travel time data were compared to speed sensor travel time data. Then a travel time index was created for I-80 from one year of speed sensor data. This travel time index was then modeled with weather variables downloaded from road weather information system (RWIS) stations. Finally, a methodology for implementing and evaluating this new travel time reporting procedure was developed. The results of this research will help to improve the current condition reporting system by incorporating both physical conditions (slick in spots, high wind speed, etc.) with travel times. This will help all types of travelers to more accurately quantify the severity of traveling conditions.
Adatok felhasználása a városi útüzemeltetés tervezésében: helyzetjelentés
The Use of Data in Planning for Operations: State-of-the-Practice Review
Szerző(k): Bauer, J., Evans, J., Jeannotte, K., Vandervalk, A.
Leidos, Cambridge Systematics, Inc, USA
Terjedelem: 66 oldal
The purpose of this state-of-the-practice review is to identify the current use of data by metropolitan planning organizations to perform planning for operations activities. This information will be used to develop the virtual data access framework and to help establish requirements for the data that should be accessible by planning agencies via the framework. In addition to data availability and use, this review also looks at the barriers to the use of data so that the project team can design the framework to help address some of these barriers to increase use of the resulting framework. This report was developed in conjunction with another state-of-the-practice review on data access, sharing, and integration.
Intelligens közlekedési rendszerek teljesítménye és összehasonlítása
ITS Performance and Benchmarking a letöltéshez ingyenes regisztráció szükséges
Szerző(k): Han, C., Khoo, Kh.Y., Byrne, M., Karl, Ch. Austroads, Australia
Terjedelem: 75 oldal
This report presents a consistent methodology to evaluate and report ITS asset performance from the road user perspective. It reviews current ITS performance evaluation practices amongst Austroads and road agencies. VicRoads methodology was adopted and generalised, and a five-step framework was established to retrieve, analyse and report on asset performance. User availability estimated from major alarms was used as the key performance indicator. Asset alarm data from SCATS signals, motorway electronic variable speed limit (EVSL) signs, and school zone electronic speed limit signs (ESLS) were collected from various Austroads jurisdictions to demonstrate the processes of the methodology. The methodology could form the basis of a national process for Austroads jurisdictions to collect, analyse and report the performance of critical ITS assets consistently across all jurisdictions.