A közlekedésépítési szakterület mérnöki és tudományos folyóirata. ISSN: 2064-0919
14. szám
8. évfolyam
2020 december
14
Bejegyzés

Nemzetközi szemle: Január

Georadar (GPR) hatékony alkalmazása az utak és hidak kritikus infrastruktúra elemeinek állapotértékelésére és megfigyelésére

Effective Implementation of Ground Penetrating Radar (GPR) for Condition Assessment & Monitoring of Critical Infrastructure Components of Bridges and Highways

Szerző(k):
Dimitrios Goulias, Michael Scott
Maryland State Highway Administration
University of Maryland, Department of Civil and Environmental Engineering USA

Terjedelem:
183 oldal

Recently Maryland State Highway Administration (SHA) started to explore use of Ground Penetrating Radar (GPR) technology to provide quantitative information for improved decision making and reduced operating costs. To take full advantage of the GPR capabilities, improved analysis techniques need to be developed and implemented. The objective of this study was to assist SHA engineers, technicians, and decision makers in their current effort to explore the use of GPR in assessing the condition of critical infrastructure components and to identify potential improvements in GPR data analysis. The research team closely interacted with representatives from selected divisions of the Office of Materials Technology (OMT) to identify potential GPR applications using existing equipment accessible to SHA, targeting critical high priority areas for analysis and improvement. In regards to pavement structures, a new methodology was suggested to improve the accuracy of GPR data analysis. The initial analysis and results indicated that Multi-scale Pavement GPR data Analysis (MPGA) has significant potential to add value and accuracy to pavement thickness data used in pavement management and rehabilitation analysis. The MPGA results indicate that pavement thickness data trends can be identified based on either automated or semi-automated procedures based on target variability levels of thickness uniformity, and thus can be used to efficiently evaluate pavement material layers. Similarly, for bridge deck analysis, techniques such as migration imaging (for concrete cover depth measurement applications among others) and Fourier analysis of GPR waveforms (for qualitative bridge deck moisture analysis) were used in addition to emerging techniques such as Short Time Fourier Transform analysis (for anticipated quantitative moisture analysis) for improving GPR data interpretation. Migration and Fourier techniques were illustrated corresponding to GPR data collected using a GPR array on selected bridge decks in the Salisbury, MD area. When applied appropriately, such techniques can provide more reliable analysis of bridge deck inspection than conventional means. In terms of precast concrete, this study has shown how GPR can be used to address several of the inspections needed in precast concrete production, including an evaluation of concrete cover depth, reinforcement location, and section thicknesses. The testing and demonstration showed significant potential for quality control using GPR.

 

Szolgáltatási szint mérőszámok (hálózat üzemeltetési tervezéshez)

Level of Service Metrics (for Network Operations Planning)

Szerző(k):
David Green, Dr. Ian Espada
Austroads Australia
Terjedelem:
87 oldal

(a letöltéshez ingyenes regisztráció szükséges)

This report documents a level of service (LOS) framework for network operations from the perspectives of different road users. The LOS framework can be applied across various user groups (private motorists, transit users, pedestrians, cyclists and freight operators) and across various transport needs (mobility, safety, access, information and amenity). The framework is to be assessed from the users’ perspective and is to be applied at a link level. The LOS framework enables integrated planning and decision making within network operations that recognises the needs of the various road user groups. It is intended that the LOS framework will aid in a better understanding of what the community considers to be an appropriate level of customer service in managing the road network. In understanding this, road agencies will be better informed to implement improvements to the management and operation of road networks that better balance the competing demands for road space. This report documents the LOS framework development, including details of literature reviewed, the process in which the LOS framework was developed, details of case studies used to refine the LOS framework, discussion of issues including further work and conclusions, and recommendations with respect to its use.

 

Kooperatív intelligens közlekedési rendszer (C-ITS) szabványok értékelése

Cooperative Intelligent Transport Systems (C-ITS) Standards Assessment

Szerző(k):
David Green, Dr Charles Karl, Freek Faber
Austroads Australia
Terjedelem:
231 oldal

(a letöltéshez ingyenes regisztráció szükséges)

The report documents the outcomes of an assessment of the emerging C-ITS standards and may be used to provide an understanding of the standards and provide guidance for determining which standards should be adopted locally. The project reviewed more than 160 standards from the ETSI release 1, CEN/ISO release 1 and from SAE and IEEE for the USA. The review identified that there are two scenarios for possible adoption by Australia and New Zealand – a US scenario comprising

IEEE and SAE standards and the EU scenario comprising standards from ETSI release 1 and CEN/ISO release 1. Of the 157 standards associated with the EU scenario, 55 were identified as being of high priority to adopt in order to deploy the EU scenario locally. Of the 11 standards associated with the US scenario, seven were identified as being of high priority to adopt in order to deploy the US scenario locally. The assessment identified and discussed key differences between the scenarios. In order to pick a scenario and commence adopting standards for deployment of the chosen scenario there is a need to seek further clarity on scenarios by participating and/or engaging in trials and initiatives; work with local stakeholders to establish a confirmed consensual direction with respect to C-ITS deployment locally; adopt the required minimum set standards for the chosen scenario; and confirm the compliance level and type required for each adopted standard and whether compliance is regulated or not.

 

Közlekedési Statisztikai Zsebkönyv 2015

2015 Pocket Guide to Transportation

Szerző(k):
Bureau of Transportation Statistics USA
Terjedelem:
64 oldal

The Pocket Guide to Transportation is a compilation of statistics that provide key information and highlight major trends on the U.S. transportation system. Intended as a compact reference, it supports the Bureau of Transportation Statistics mission to create, manage, and share transportation statistical knowledge. Many of the tables and figures within this publication are derived from National Transportation Statistics available at www.bts.gov. Contents: A Dynamic System, Infrastructure, Moving People, Moving Goods, Performance, Economy, Safety, Environment, Glossary.

 

Biztonságosabb sebességek: közösségi elfogadás és megfelelőség

Safer speeds: public acceptance and compliance

Szerző(k):
S. Turner, S. Bosher, D. Logan, J. Khoo, H. Trumper
New Zealand Transport Agency
Terjedelem:
147 oldal

A key element of the Safer Journeys national road safety strategy is safer speeds. In some cases, particularly where investment to make roads safer at current speeds cannot be justified, this means reduced speed limits for both urban and rural roads. This research considered the level of acceptance of and compliance with reduced speed limits. It examined information from a number of speed limit changes around New Zealand, including town centres, along strip shopping, suburban streets, mountainous roads, flat state highways and local roads. Before and after speeds were compared for any speed reductions and driver compliance. The acceptance of reduced speed limits was researched using the limited literature available on this topic, a web questionnaire survey and the experience of three local councils. These showed a greater acceptance of reduced speed limits on hilly and mountainous rural roads and in shopping streets. There was less acceptance for reduced speed limits in suburban streets (except immediately around schools) and on straight flat rural roads with a lot of roadside hazards and frequently occurring priority intersections. Drivers do not appear to understand the crash risks of these scenarios, even when relatively extensive media and consultation programmes are undertaken.

 

Gyalogos és kerékpáros forgalmi adatgyűjtési módszerek és technológiák

Methods and Technologies for Pedestrian and Bicycle Volume Data Collection

Szerző(k):
Paul Ryus, Erin Ferguson, Kelly M. Laustsen, Frank R. Proulx, Robert J. Schneider, Tony Hull, Luis Miranda-Moreno
Transportation Research Board National Cooperative Highway Research Program USA
Terjedelem:
226 oldal

This report documents and presents the results from NCHRP Project 07-19, Methods and Technologies for Pedestrian and Bicycle Volume Data Collection. This project tested and evaluated a range of automated count technologies that capture pedestrian and bicycle volume data. The focus of the study was to evaluate the technologies in different count settings, including ranges of temperature, varying weather conditions, mixed traffic conditions, mixed travel directions, and different facility types (e.g., roadways, multiuse paths), to determine their accuracy and reliability in different contexts. This report documents the project’s findings on the accuracy and consistency found for the different automated count technologies. It provides a complete account of the process used to select technologies for testing, identify test sites, and evaluate the effectiveness of the technologies. It is clear from the testing that it is critical for practitioners to calibrate and evaluate the effectiveness of the counters they install at specific sites to have the most accurate understanding of how well the counters capture non-motorized volumes under site-specific conditions.

 

Gyalogos és kerékpáros forgalmi adatgyűjtési kézikönyv

Guidebook on Pedestrian and Bicycle Volume Data Collection

Szerző(k):
Paul Ryus, Erin Ferguson, Kelly M. Laustsen, Frank R. Proulx, Robert J. Schneider, Tony Hull, Luis Miranda-Moreno
Transportation Research Board National Cooperative Highway Research Program USA
Terjedelem:
159 oldal

NCHRP Report 797: Guidebook on Pedestrian and Bicycle Volume Data Collection is directed to practitioners involved in collecting non-motorized count data. The Guidebook (1) describes methods and technologies for counting pedestrians and bicyclists, (2) offers guidance on developing a non-motorized count program, (3) gives suggestions on selecting appropriate counting methods and technologies, and (4) provides examples of how organizations have used non-motorized count data to better fulfill their missions. The research behind the Guidebook can be found on the TRB website as NCHRP Web-Only Document 205: Methods and Technologies for Pedestrian and Bicycle Volume Data Collection (NWOD 205). NWOD 205 includes the results of the testing and evaluation of a range of automated count technologies that capture pedestrian and bicycle volume data.

 

Lézerszkenner felhasználási lehetőségének vizsgálata a forgalmi sebességgel történő vagyonelem felmérésben és értékelésben

Investigation into the potential of LiDAR to support traffic speed asset measurement and assessment

Szerző:
Dean Wright
Transport Research Laboratory UK
Terjedelem:
43 oldal

(a letöltéshez ingyenes regisztráció szükséges)

The Highways Agency conducts routine automated surveys of trunk road pavement surface (TRACS) and structural (TSD) condition. From these surveys, the Agency is able to establish the condition of the network, prioritise reconstruction and repair work and value its road assets. However, the infrastructure of the trunk road network includes assets other than pavements – the network contains bridges, signs, gantries, lighting, embankments, drainage systems and many types of roadside furniture – none of which are assessed using current automated routine surveys. This report details an investigation into the potential for the use of LIDAR as a routine tool for the measurement and assessment of road infrastructure assets, and to determine how this information could be used to assist the effective management of the network. LIDAR (Light Detection And Ranging) uses directed laser light to identify the locations and ranges of objects in the field of view of a sensor. LIDAR is similar to RADAR, but by using shorter wavelengths and exploiting the coherency of laser light LIDAR operates at greater spatial accuracies over shorter distances. LIDAR applications include atmospheric surveying, remote sensing and obstacle detection in automated systems. Although operating with lower accuracy than the lasers used in TRACS (LIDAR systems deliver data in the ~cm accuracy range) LIDAR has potential for use in the measurement of many roadside infrastructure assets.

 

Mart aszfalt felhasználási lehetősége alaprétegekben és útalapokban

Feasibility of Reclaimed Asphalt Pavement (RAP) Use as Road Base and Subbase Material

Szerző(k):
Edward J. Hoppe, D. Stephen Lane, G. Michael Fitch, Sameer Shetty
Virginia Center for Transportation Innovation and Research
Terjedelem:
42 oldal

The purpose of this study was to investigate the current state of the practice with regard to the use of reclaimed asphalt pavement (RAP) material for road base and subbase applications and the potential for such use by the Virginia Department of Transportation (VDOT). To achieve the objectives of the study, a comprehensive review of the literature was conducted and the current state of the practice by other state departments of transportation was analyzed. The results indicated that the use of RAP in road base and subbase materials is viable and has been implemented by a number of transportation agencies. There seemed to be no major environmental concerns associated with using unbound RAP without chemical stabilization agents. Numerous sources of RAP are available in Virginia. Based on practices adopted by other state transportation agencies, the study recommends that VDOT allow the use of RAP in a road base material on highway construction projects. The study further recommends that the allowable percentage of RAP in a blend be phased in gradually to allow VDOT to gain familiarity with the materials and processes involved. Compaction testing could be performed with current methods while alternative procedures were analyzed for suitability. Once a standard specification has been developed, sites for long-term field studies will be identified to implement further the recommendations stemming from this study. There is a potential for significant economic benefits if RAP is used in base and subbase applications. Approximately 30% in material cost savings could be realized with a 50/50 blend of RAP and virgin aggregate. In addition, this application would likely result in a substantial reduction in the amount of RAP material currently stockpiled in Virginia.


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