A közlekedésépítési szakterület mérnöki és tudományos folyóirata. ISSN: 2064-0919
13. szám
8. évfolyam
2020 április
13
Bejegyzés

Nemzetközi szemle: Szeptember

A közúti infrastruktúra megőrzése, fenntartása és felújítása

Preservation, Maintenance, and Renewal of Highway Infrastructure

Szerző(k): J. Mallela, S. Sadasivam, R. Giordano, H. Kassoff, S. Lockwood

WSP USA Inc.

Link: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_750-v7.pdf

Terjedelem: 244 oldal

Kivonat:

This study identified and described emerging and innovative practices that could influence long-range PMR needs of highway infrastructure and provided technical guidance for transportation leaders and practitioners on assessing their application. The research recognized a wide range of plausible futures in terms of drivers that could bring change and practices that could emerge over the next 30 to 50 years. Because the range of plausible futures over such a long-term period is very broad, making a focused prediction of the implications for highway infrastructure PMR is quite challenging. The vision becomes more blurred as the planning horizon extends decades further into the future. For this reason, this study emphasized the need for preparation for plausible futures rather than on their prediction with any degree of precision.

 

Aszfaltkeverékek újrahasznosítás segítő összetevőinek hatásértékelése magas újrahasznosított kötőanyag arányok mellett

Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios

Szerző(k): Epps, M.F. Kaseer, E. Armbula-Mercado, A. Baja, L. Garcia Cucalon, F. Yin, A. Chowdhury, J. Epps, C. Glover, E.Y. Hajj, N. Morian, J. Sias Daniel, M. Oshone, R. Rahbar-Rastegar, C.  Ogbo, G. King

Texas A&M Transportation Institute USA

Link: https://www.nap.edu/download/25749

Terjedelem: 283 oldal

Kivonat:

More than 90% of highways and roads in the United States are built using hot-mix asphalt (HMA) or warm-mix asphalt (WMA) mixtures, and these mixtures now recycle more than 99% of some 76.2 million tons of reclaimed asphalt pavement (RAP) and about 1 million tons of recycled asphalt shingles (RAS). According to the National Asphalt Pavement Association (NAPA), cost savings in 2017 totaled approximately $2.2 billion with these recycled materials replacing virgin materials. Highway agencies and the paving industry have developed a renewed interest in using larger quantities of recycled materials (RAP and RAS) to maximize economic and environmental benefits that include conservation of natural resources (aggregate, binder, fuel, etc.), reduction in energy consumption, and reduction in emissions (including greenhouse gases). In spite of these symbiotic benefits, state departments of transportation (DOTs) limit the use of RAP and RAS in asphalt mixtures for reasons that include variability of the recycled materials and concerns about long-term mixture performance. In addition, mix design is more complicated and more time consuming, particularly with large quantities of recycled materials identified by high recycled binder ratios (RBRs) between 0.3 and 0.5. National Cooperative Highway Research Program (NCHRP) Project 9–58, “The Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios,” focused on using recycling agents to facilitate increasing RBR and met the following study objectives: Assess the effectiveness of recycling agents at a selected dose to partially restore binder blend rheology and improve mixture cracking performance without adversely affecting rutting resistance, Evaluate the evolution of recycling agent effectiveness with aging, and Recommend evaluation tools for assessing the effectiveness of recycling agents initially and with aging for mixtures with high RBRs in specific climatic regions. Many materials combinations were used; these included 10 base binders, 6 RAP sources, 5 RAS sources, 5 aggregate types, and 10 recycling agents. Laboratory testing results and field performance at five field projects in Texas, Indiana, Nevada, Wisconsin, and Delaware facilitated engineering rejuvenated binder blends and corresponding mixtures and the development of evaluation tools for assessing the effectiveness of recycling agents initially and with aging for binders and mixtures with high RBRs.

 

Biztonságos mikró mobilitás

Safe Micromobility

Szerző(k): The International Transport Forum OECD

Link: https://www.itf-oecd.org/sites/default/files/docs/safe-micromobility_1.pdf

Terjedelem: 98 oldal

Kivonat:

This report examines the traffic safety of pedal cycles, electrically assisted cycles and electrically powered personal mobility devices such as e-scooters, whether owned or shared, in an urban context. In a fast-evolving urban transport environment, micromobility is changing how people move on a daily basis. This brings new and urgent challenges for national policymakers and city officials. The report proposes a framework to define micromobility which includes all the above vehicles and suggests certain limits on mass and speed to classify them. It also compares the safety of powered standing scooters (e-scooters) to that of bicycles, mopeds and motorcycles. The report defines micromobility as the use of vehicles with a mass of less than 350 kg and a design speed of 45 km/h or less. This definition limits the kinetic energy of such micro-vehicles to 27 kJ, one hundred times less than the kinetic energy reached by a compact car at top speed. The report classifies micro-vehicles into four types based on their speed and mass: Type A micro-vehicles have a mass of up to 35 kg and their power supply (if any) is electronically limited so the vehicle speed does not exceed 25 km/h (15.5 mph). Many bicycles, e-bikes, e-scooters and self-balancing vehicles fall into this category. Other types of micro-vehicles have a higher mass (Type B) or speed (Type C) or both higher mass and higher speed (Type D). The report proposes a range of safety improvements for micromobility. These relate to vehicle design, fleet operation, infrastructure, regulatory enforcement and training. It proposes future-proof, balanced safety regulations proportional to the risks imposed. The analysis draws on the results of a workshop attended by 40 participants from 15 countries in October 2019.

 

Friss közösségi közlekedési utazási trendek elemzése (2020

Analysis of Recent Public Transit Ridership Trends (2020)

Szerző(k): K. Watkins, S. Berrebi, C. Diffee, B. Kiriazes, D. Ederer

Georgia Tech Research Corporation USA

Link: https://www.nap.edu/download/25635

Terjedelem: 111 oldal

Kivonat:

The objectives of this research were to produce a current snapshot of public transit (bus and rail) ridership trends in urban and suburban areas in the U.S., focusing on what has changed in the past several years, and explore and present strategies that transit agencies are considering and using for all transit modes in response to changes in ridership. The research approach included a literature review, transit ridership analysis, and case studies. Transit ridership across the United States has declined for six straight years. Bus ridership, which has declined more than other transit services, is now at the lowest point since at least 1973. Rail ridership, with the exception of commuter rail, has also declined, and commuter rail ridership has recently leveled off.

 

A percek számítanak: közösségi autóbusz szolgáltatás megbízhatósági útmutató (2020)

Minutes Matter: A Bus Transit Service Reliability Guidebook (2020)

Szerző(k): A. Danaher, J. Wensley, A. Dunham, T. Orosz, R. Avery, D. Turner, K. Cobb, K. Watkins, C. Queen, S. Berrebi, M. Connor, J. McLaughlin

WSP USA, Georgia Tech University, MCA Associates, USA

Link: https://www.nap.edu/download/25727

Terjedelem: 158 oldal

Kivonat:

This Guidebook is intended to help inform public transit agencies, local governments and planning agencies, potential service operators and sponsors, and other stakeholders about how agencies can identify and address transit service reliability issues in a variety of operating environments. The focus of the Guidebook is on fixed-route bus service, the most extensive transit mode applied in the United States and around the world. The Guidebook provides an overview and taxonomy of bus service reliability measures, assessment tools, and improvement strategies that exist in the U.S. today, as well as a multi-step reliability improvement program agencies can implement to address bus service reliability issues in a more structured manner.

 

Mobilitás teljesítmény mutatók (MPM) az integrált mobilitásért és tovább

Mobility Performance Metrics (MPM) For Integrated Mobility and Beyond

Szerző(k): TransitCenter, Applied Predictive Technologies, Texas A&M Transportation Institute, USA

Link: https://www.transit.dot.gov/sites/fta.dot.gov/files/docs/research-innovation/147791/mobility-performance-metrics-integrated-mobility-and-beyond-fta-report-no-0152.pdf

Terjedelem: 195 oldal

Kivonat:

This report presents traveler-centric mobility performance strategies and metrics and the approach for the development of those metrics for use as supplemental measures to assess how well an integrated public/private mobility system meets the needs of individual travelers, how well the system performs while meeting overall travel demand, and what the system’s impact is locally and nationally. By measuring transportation performance from the traveler’s perspective, agencies and operators can be incentivized to improve service based on what matters most to travelers. The report identifies a large set of potential measures that align with Federal Transit Administration (FTA) goals as well as goals of the Mobility on Demand (MOD) Sandbox Projects. It then presents a comprehensive evaluation process using applicability and feasibility criteria that were used to cull the potential performance measures to a smaller more appropriate set of performance measures. The reports discusses possible data sources and data integration strategies for the application of the new mobility performance measures.

 

Forgalomnagyság becslések javítása a Minnesota-i Regionális Közlekedésirányítási Központban

Improve Traffic Volume Estimates from MnDOT’s Regional Traffic Management Center

Szerző(k): T. Kwon

University of Minnesota USA

Link: http://www.dot.state.mn.us/research/reports/2020/202002.pdf

Terjedelem: 102 oldal

Kivonat:

The Regional Transportation Management Center (RTMC) at the Minnesota Department of Transportation (MnDOT) deploys a large number of traffic detectors in the Twin Cities’ freeway network and continuously collects traffic data. While RTMC mainly uses the data for traffic and incident management, the TFA (Traffic Forecasting and Analysis) office uses the same data for monitoring, forecasting, planning, and reporting of transportation applications. RTMC provides current and historical volume data generated from its freeway network, but it does not provide quality information on that data. The objective of this project was to develop a new tool that can quickly explore the quality of detector data. To allow exploration of data quality, 13 detector-health parameters were computed using raw volume and occupancy data and then they were stored in a relational database. The final detector-health system was implemented as a client server-based system, in that a single server served many remote clients through the Internet. This report provides descriptions of the detector-health parameters, principles applied, server implementation, client software, and some analyses and application examples.

 

Utazási igény menedzsment: stratégiák és eredmények

Travel demand management: strategies and outcomes

Szerző(k): A.Carran-Fletcher, C. Joseph, F. Thomas, S. Philbin

MRCagney, Traffic Planning Consultants, New Zealand

Link: https://www.nzta.govt.nz/assets/resources/research/reports/661/661-travel-demand-management-strategies-and-outcomes.pdf

Terjedelem: 188 oldal

Kivonat:

Travel demand management (TDM) is being implemented in numerous different ways throughout the world, to address congestions issues and encourage modal shift. This research outlines some of the many TDM strategies being used internationally to provide insights of potential value for the New Zealand context. This information is presented through six city case studies and 10 focus areas. The cities (Amsterdam, London, Singapore, Sydney, Seattle and Vancouver) were chosen to provide variety in approach. The focus areas analyse specific approaches to TDM through investigations of initiatives. The research identified seven critical insights: clearly defined and communicated TDM goals are important; the term TDM is used inconsistently; integration and prioritisation of TDM principles in wider policy maximises effectiveness; reliable alternative transport infrastructure and services are needed for modal shift; there are no TDM ‘silver bullets’; major events or construction projects create opportunities to trial TDM strategies; persuasive technologies have benefits and challenges; and TDM policies need to account for emerging mobility trends and services. Rapid technological changes are providing opportunities and complexities for TDM strategies and areas of future study include issues of equity and accessibility, and the potential of future mobility technologies and choices.


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