A közlekedésépítési szakterület mérnöki és tudományos folyóirata. ISSN 2064-0919
10. szám
2017. ősz
10
Bejegyzés

Nemzetközi szemle: November

Aszfalt burkolatok határfelületi állapot értékelése a tapadási teljesítmény javítására

Evaluation of Asphalt Pavement Interface Conditions for Enhanced Bond Performance
Szerző(k):
R. Roque, D. Hernando, B. Park, J. Zou, J.A.M. Waisome
University of Florida USA
Terjedelem: 161 oldal

This project describes a comprehensive modeling effort aimed at examining the potential impact of interface debonding on near-surface longitudinal cracking in the wheelpath of asphalt pavements. A critical zone defined by high shear stress coupled with low confinement was found at a depth of about 2 in and extending to 2 in from the edge of the tire, regardless of asphalt layer thickness. These critical stress states can promote a debonded strip below the wheelpath if an interface is located at an approximate depth of 2 in. The introduction of a debonded strip along the interface caused a stress redistribution that intensified shear stress ahead of the tip of the debonded zone and tensile stress immediately behind the tip (tension at this location exceeded that under the tire). A finite element parametric study based on maximum tension and maximum Von Mises stress (associated with the strain energy of distortion) identified three potential mechanisms of near-surface longitudinal cracking in an asphalt pavement with localized interface debonding: (1) bending caused by repeated traffic can initiate a crack below the edge of the debonded strip that reflects to the surface due to traffic wander and thermal cycles, especially given near-surface differential aging; (2) traffic wander can initiate a vertical crack above the edge of the debonded strip and promote upward propagation; and (3) internal tension due to partially restrained dilation can result in a crack that propagates upward through the more aged and less fracture-tolerant mixture near the surface. Future work should focus on achieving a better understanding of the mechanism of interface breakdown to prevent debonding in the first place. Identification of bonding agents more resistant to interface bond breakdown can help prevent and, in turn, mitigate the occurrence of near-surface longitudinal cracking.

 

A vezető nélküli közúti teherszállítás felé történő átmenet irányítása

Managing the Transition to Driverless Freight Transport
Szerző(k):
International Transport Forum
Terjedelem: 75 oldal

This report explores how a transition to driverless trucks could happen. Reduced reliance on humans to move road freight offers many benefits. It also threatens to disrupt the careers and lives of millions of professional truck drivers. Based on different scenarios for the large-scale introduction of automated road freight transport, this study makes recommendations to help governments manage potential disruption and ensure a just transition for affected drivers. Three leading transport-sector organisations joined the International Transport Forum for this project to assess benefits, costs and risks of a transition to driverless trucks. The International Road Transport Union, the International Transport Workers’ Federation and the European Automobile Manufacturers Association contributed insights on driverless technology in the road freight sector as well as funds for the research.

 

Az élhetőség javítása zöld és aktív közlekedési módokkal: a közösségi, a kerékpáros és a gyalogos elérhetőség és mobilitás forgalmi stressz szint elemzése

Improving Livability Using Green and Active Modes: A Traffic Stress Level Analysis of Transit, Bicycle, and Pedestrian Access and Mobility
Szerző(k):
M.C. Mekuria, B. Appleyard, H. Nixon
Mineta Transportation Institute, USA
Terjedelem: 57 oldal

Understanding the relative attractiveness of alternatives to driving is vitally important toward lowering driving rates and, by extension, vehicle miles traveled (VMT), traffic congestion, greenhouse gas (GHG) emissions, etc. The relative effectiveness of automobile alternatives (i.e., buses, bicycling, and walking) depends on how well streets are designed to work for these respective modes in terms of safety, comfort and cost, which can sometimes pit their relative effectiveness against each other.
In this report, the level of traffic stress (LTS) criteria previously developed by two of the authors was used to determine how the streets functioned for these auto alternative modes. The quality and extent of the transit service area was measured using a total travel time metric over the LTS network. The model developed in this study was applied to two transit routes in Oakland, California, and Denver, Colorado.

 

A közösségi közlekedés és az innovatív mobilitás kapcsolatának alakítása

Shaping the Relationship between Public Transport and Innovative Mobility

Szerző(k):
International Transport Forum
Terjedelem: 56 oldal

This report investigates the convergence of public transport and innovative mobility solutions, such as ride services, car- and bicycle-sharing, app-enabled on-demand micro-bus services, and platforms that connect app-using travellers and drivers. It examines the role of public authorities in ensuring this convergence supports commercial innovation as well as public policy objectives and identifies principles to guide partnerships between innovative mobility services and public transport operators. The report also explores where action may be needed to ensure that this convergence does not lead to reduced mobility options for those that have difficulty using existing transport modes, and in particular, how the needs of an ageing population may be met in an evolving mobility service landscape. This study was organised under the auspices of the International Transport Forum’s Corporate Partnership Board (CPB). It is based on a workshop with commercial actors, public authorities and other experts that took place in November 2016, and interviews with various officials and experts as well as input from CPB member companies. Additionally, extensive desk research for this study was carried out by the International Transport Forum.

 

A távoliság és az elérhetőség mérése – mutatószámok kanadai közösségek számára

Measuring remoteness and accessibility - A set of indices for Canadian communities
Szerző(k):
Alasia, F. Bédard, J. Bélanger, E. Guimond, C. Penney
Statistics Canada
Terjedelem: 48 oldal

This study was undertaken in response to the need to update and upgrade the current measures of remoteness. The objective was to conceptualize and implement a method that takes into account the most recent literature on the subject, as well as taking advantage of new computational opportunities provided by the integration of official statistics with data from non-official statistical sources. The focus of the analysis was on the concept of “remoteness” and, consequently, on the creation of an index of remoteness for Canadian communities. However, through the process of developing the index and testing for alternative specifications it was felt that a set of accessibility measures to selected services computed with a similar methodology could provide further information for specific research and policy purposes. Furthermore, it was found that the comparison of accessibility measures with the remoteness index implemented in this analysis provided support to the view that the latter could serve as a good proxy for service accessibility.

 

Az első nemzetközi útmenti biztonsági konferencia

First International Roadside Safety Conference
Szerző(k):
Transportation Research Board USA
Terjedelem: 852 oldal

This publication contains papers and abstracts presented at the TRB First International
Roadside Safety Conference: Safer Roads, Saving Lives, Saving Money; June 12-15, 2017;
San Francisco, California. The primary objective of the Conference was to support and advance global efforts to reduce deaths and serious injuries associated with run-off-road crashes. The TRB First International Roadside Safety Conference contributed to this objective through: peer exchange and improved dissemination of information within the international roadside safety community; increased collaboration amongst international roadside safety experts, researchers, government agencies, and engineering consultants; and assisting with a more rapid implementation of new technologies, best practices, and products from around the world. The E-Circular is organized by the conference subthemes: Advancements in Roadway Safety Features; Innovations in Roadside Safety Hardware and Features; Roadside Safety Design and Hazard Mitigation; Roadway Departure Data Collection and Analysis; Safety Policy, Guidelines, Plans, Programs, and Strategies; Simulation, Testing, and Evaluation Methods; and Vehicle Technologies and Safety Considerations. The views expressed in the papers and the abstracts contained in this publication are those of the authors and do not necessarily reflect the views of the Transportation Research Board, the National Academies of Sciences, Engineering and Medicine, the National Research Council, or the cosponsors of the conference. The papers were subject to a formal TRB peer review process, having a minimum of three reviews.

 

Közösségi közlekedés Park-and-Ride létesítményeinek tervezési döntés-segítő eszköztára: Park-and-Ride tervezési és irányítási kézikönyv

Decision-Making Toolbox to Plan and Manage Park-and-Ride Facilities for Public Transportation: Guidebook on Planning and Managing Park-and-Ride
Szerző(k):
L.K. Cherrington, J. Brooks, J. Cardenas, Z. Elgart, L.D. Galicia, T. Hansen, K. Miller, M.J. Walk, P. Ryus, C. Semler, K. Coffel
Texas A&M Transportation Institute, Kittelson & Associates, Inc., Kathryn Coffel Consulting, LLC, USA
Terjedelem: 145 oldal

This Guidebook provides public transportation agencies with guidance to develop park-and-ride facilities from concept through operation. The guidebook presents information about best practices and lessons learned gathered via a literature review, an industry scan, and detailed case study research with transit agencies in the United States and Canada. It was developed as the lead research product from TCRP Project H-52, “Decision-Making Toolbox to Plan and Manage Park-and-Ride Facilities for Public Transportation.” The guidebook begins with an overview of park-and-ride; includes two sections on planning - strategic and financial; provides guidance on design and implementation; addresses operating and charging for park-and-ride as well as interacting with the community; discusses maintenance, asset management, and state-of-good-repair practices; and offers information on the potential for park-and-ride facilities to also serve as sites for transit-oriented development.

 

Közösségi közlekedés Park-and-Ride létesítményeinek tervezési döntés-segítő eszköztára: Kutatási jelentés és közösségi közlekedésszervező esettanulmányok

Decision-Making Toolbox to Plan and Manage Park-and-Ride Facilities for Public Transportation: Research Report and Transit Agency Case Studies
Szerző(k):
L.K. Cherrington, J. Brooks, J. Cardenas, Z. Elgart, L.D. Galicia, T. Hansen, K. Miller, M.J. Walk, P. Ryus, C. Semler, K. Coffel
Texas A&M Transportation Institute, Kittelson & Associates, Inc., Kathryn Coffel Consulting, LLC, USA
Terjedelem: 513 oldal

This document summarizes the technical research and presents the in-depth park-and-ride case studies in two parts. Part 1 summarizes the research findings and Part 2 documents 16 case studies. Part 1 includes findings from the literature review, documents a state-of-the-practice scan and park-and-ride inventory, discusses how transit agencies model demand for park and-ride facilities, and summarizes a review of demand estimation models. Part 1 also describes the case study research methodology, and outlines the guidebook developed using case study findings. Part 2 documents 16 case studies to provide in-depth discussion of the experiences and best practices for the park-and-ride facilities. Case study findings may contain information of interest to other transit agencies that operate park-and-ride facilities or are considering developing new facilities.

 

A járművek tengelyterhelése és a helyi utak burkolatának romlása közötti kapcsolat

The relationship between vehicle axle loadings and pavement wear on local roads
Szerző(k):
G. Arnold, T. Henning, D. Alabaster, F. Greenslade, A. Fussell, R. Craw
Road Science, Auckland University, NZ Transport Agency, New-Zealand
Terjedelem: 110 oldal

In New Zealand heavy vehicles are charged for using the road based on the damage caused passing over the road. The current approach to charging has its origins in American research that found doubling an axle load increased the damage as a power function with an exponent of 4, known as the Fourth Power Law. This was developed with limited pavement and vehicle load types not representative of most of the roads in New Zealand. This research provided reliable evidence on the wear characteristics of New Zealand local road pavements from accelerated pavement loading studies at the Canterbury Accelerated Pavement Testing Indoor Facility (CAPTIF). The aim was to determine the relative damage on different pavement types/strengths. The data was extended with rut depth modelling with repeated load triaxial data and validated with field data from the nationwide long-term pavement performance sites. A relationship was found between pavement life tested at CAPTIF plus the rut depth modelling and the damage law exponent for the 4 and 6 tonne equivalent axle loads. For short-life pavements the damage law exponent increased.

 

Az emberek és helyek összekapcsolása. A térbeli elérhetőség megértésének új módjai a városokban

Linking People and Places. New ways of understanding spatial access in cities
Szerző(k):
International Transport Forum, OECD
Terjedelem: 67 oldal

Spatial accessibility relates to how, and how well, people access each other, jobs, services and opportunities. This report examines how different people and groups experience spatial accessibility in cities. It reviews the latest research findings, methodologies and data sources on urban accessibility and discusses how better data and computing power have improved accessibility analysis and mapping, and made it more relevant to people. This study presents the results of several projects on accessibility measurement carried out by the International Transport Forum. They illustrate how new data sources can be used to refine accessibility analyses and ultimately transport planning. Building upon these experiments, general lessons on how to increase the relevance of accessibility studies are drawn. The findings were discussed and refined in a workshop with 15 experts from seven countries held in Mexico City in October 2016.

 


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