Increase In Traffic Volume Research Articles

Economic benefits of road widening: Discrepancy between outturn and forecast

Abstract Cost-benefit analysis of road investments involves models that generate travel time savings as the main economic benefit. Monitoring of traffic flows after the widening of the section of the M25 London orbital motorway between Junctions 23 and 27 found substantial increases in traffic volumes, of up to 23% two to three years after opening, but no increase in speed of travel beyond the first year. Comparison was made with the forecast traffic flows, made using a variable demand model based on SATURN software. The model projected increased traffic volumes and speeds as a consequence of road widening, but underestimated traffic volumes and overestimated traffic speeds compared to outturn. The forecast of faster traffic speeds was the input to the economic model used to compare investment benefits with costs, yielding a benefit-cost ratio of 2.9, which justified the investment. However, the absence of observed increase in traffic speed raises questions about the applicability of a long-established transport model and of travel time savings as the main economic benefit of road investment, as well as about the value of investment to increase the capacity of strategic roads where these are used extensively for local trips.

Traffic Optimization Methods of Urban Multi-leg Intersections

The research on the organization of intersections has always been the key and difficult point of road optimization, especially for multi-leg intersections. Since the traffic flow direction and the number of conflict points of multi-leg intersection are more than that of ordinary intersection, the difficulty of organization and optimization increases accordingly. At present, the research on multi-leg intersections is not much or deep enough at home and abroad. In general, it is transformed into a roundabout when the traffic volume is small, and the signal lamp is set with the increase of traffic volume. However, the signalized roundabout is not applicable when the traffic flow at the signal roundabout increases to a certain extent. Therefore, this paper introduces Huangsha six import signal free roundabout in Dianjiang County of Chongqing as the research case, takes the traffic delay and queue length as the evaluation index, and two new optimization methods are proposed on the basis of the original methods, namely improved the signalized roundabout and the signalized intersection. To assess the feasibility of these methods, VISSIM is used for simulation comparison. The simulation results show that compared with the current traffic situation, the average delay time of vehicles in the signalized intersection optimization method is reduced by 9.3 s, the average queue length decreased by 3.7 m, and its indicators are better than the signalized roundabout. Therefore, the method of signalized intersection not only provides a good mirror for the reconstruction of multi-leg intersections, but also offers relevant theoretical and practical exploration.

Dynamic control cycle speed limit strategy for balanced reduction of travel time and emissions

The vehicle exhaust has been one of the major sources of greenhouse gas emissions. With an increase in traffic volume, it has been found that the introduced intelligent traffic control is necessary. This paper investigated a novel VSL strategy considering the dynamic control cycle to improve the traffic efficiency and environmental benefit on freeway. An extension of the cell transmission model (CTM) was used to depict the traffic characteristics under VSL control, and integrated with the microscopic emission and fuel consumption model VT-Micro to estimate the pollution emission of each cell. The VSL strategy was designed to provide multiple control cycles with different length to adjust the scope of VSL changes, furthermore, a probability formula was developed and used to determine the optimal quantity of control cycles to reduce the computational complexity of controller. An objective optimization function was formulated with the aim of minimizing total travel time and CO emission. With simulation experiments, the results showed that the proposed VSL strategy considering the dynamic control cycle outperformed uncontrolled scenario, resulting in up to 8.4% of total travel time reductions, 26.7% of delay optimization, and 14.5% reduction in CO emission, which enhanced the service level of freeway network.

Analysis of Changes and Factors Influencing Air Pollutants in the Beijing-Tianjin-Hebei Region During the COVID-19 Pandemic

A series of strict control measures were imposed in the Beijing-Tianjin-Hebei region in early 2020 to control the spread of COVID-19. These measures have led to a reduction of anthropogenic air pollutants, providing an opportunity to observe the contribution of human activities to local air pollution. In this study, the control period was divided into four stages:the before, early, middle, and later stages. Based on a variety of data including meteorological, traffic, and industrial manufacturing datasets, statistical methods were combined with spatial analysis to evaluate changes in air pollution and associated human impacts during each stage. In addition, suggestions are made for further regional air pollution control in the Beijing-Tianjin-Hebei area. Key results are as follows:① Overall, the AQI and the concentrations of six air pollutants, especially SO2, PM10, and NO2, were lower during control period than during the equivalent period in 2019 (reductions of 26.5%, 24.3%, and 16.9%, respectively). From the before to later stages, pollutants (except O3) showed a downward trend while O3 increased significantly during the before stage (by 76.2%) and the growth rate slowed during the middle and later stages; ②During the prior stage, Beijing experienced two periods with heavy air pollution days as a result of the local accumulation of pollutants, secondary transformation, and regional transport. The concentration of PM2.5 in February was nearly 60% lower than in February 2014 under similar meteorological conditions in Beijing; ③ Following an increase in traffic volume and industrial activity, changes in air pollutants tended to be stable or slightly increase during the middle and later stages of the control period. The grey relation coefficients between thermal radiation intensity anomalies and the main pollutants in heavy industrial cities were greater than 0.6, which means that the control of industrial emissions remains key to controlling air pollution.

Compatibility of Automated Vehicles in Street Spaces: Considerations for a Sustainable Implementation

Automated Vehicles (AVs) will bring a fundamental change in the mobility sector in the coming years. Whereas many studies emphasize opportunities with AVs, studies on the impacts of AVs on travel behavior particularly show an overall increase in traffic volume. This increase could impair the needs of other uses and users within street spaces and decrease the permeability of the street space for pedestrians and cyclists. However, only a few studies, so far, have looked at the changes of traffic volume due to AVs at the street level, and to what extent these impair the needs of other uses and users within different street spaces was not in the focus at all. This paper investigates the compatibility of AVs in street spaces, building on different modeling results of scenarios with AVs based on the Multi-Agent Traffic Simulation (MATSim) framework. Using the so-called compensatory approach and the whole street network of Vienna, Austria, as a case study, we examine how compatible AVs and their related changes in traffic volume are with the needs of other uses and users, i.e., pedestrians and cyclists, within different street spaces, by specifically considering the various characteristics of the latter. Results show that the effects of AVs on the compatibility of street spaces would be unevenly distributed across the city. For Shared Automated Vehicles (SAVs), a deterioration in compatibility is observable, especially in inner-city dense areas, because of an increase in traffic volume and an already high amount of competing uses. In contrast, especially (on main roads) in the outskirts, improvements in compatibility are possible. This particularly applies to SAVs with a stop-based service. However, private AVs interlinked with an overall capacity increase would lead to a deterioration in compatibility, especially in parts of the higher-level street network that already have incompatible traffic volumes, further increasing the separating or barrier effect of such streets. The results can provide insights for policymakers and stakeholders about where and how to facilitate AVs, to reach an implementation that is compatible with the different uses and needs of users within street spaces: While SAVs should be implemented particularly in the outskirts, as a complement for public transport, an implementation of AVs in the lower-level street network in inner parts of the city should not be facilitated, or it should at least be linked to measures that make street spaces more compatible with the needs of pedestrians and cyclists, e.g., implementation of walking and cycling infrastructure.

Research on the Construction Technology of Tunnel Internal Air Circulation Purification under High-Quality Air Quality

As the traffic volume increases, the air quality in the tunnel decreases. In order to ensure the health of the tunnel staff and the safety of tunnel operation, and to better play the role of the duty room in the tunnel, through the test and analysis of the tunnel ventilation and environment, it is proposed to take the air in the tunnel and circulate the purification and the roots blower to send and exhaust air. The design scheme combining methods effectively solves the design problems of small air volume and high air pressure of the air purification system in the tunnel, and has reference significance for the safe operation of similar long road tunnels.

Performance Evaluation of Studded Tire Ruts for Asphalt Mix Designs in a Cold Region Environment

Studded tire wear is one of the most important contributing factors that govern pavement life on high traffic volume roads in south-central Alaska. It has been estimated that the annual cost to repair damage caused by studded tires in Alaska is approximately $13.7 million. Polymer modified asphalt binders and hard aggregate are commonly used in mix designs in the State of Alaska Department of Transportation and Public Facilities projects in an attempt to resist studded tire wear. This research provides a field performance-based analysis of the use of hard aggregate and polymer modified binders related to the reduction of the impact of studded tire wear. To analyze the performance of modification in asphalt mix designs, roadway data was gathered from the Alaska Department of Transportation Pavement Management System Database and roads were grouped into deterioration families based on mix design properties. Relationships of each deterioration are presented to show cumulative average annual daily traffic versus total rut depth, comparing mix designs with and without hard aggregate and polymer modification. Findings indicated that both polymer modification and hard aggregate can be used to reduce the impact of studded tire wear. The benefits of polymer modification and hard aggregate proved more significant as cumulative traffic volumes increase. Recommendations from the performance analysis included continuing the use of hard aggregate and polymer modified binders on Alaskan roadways with continuous research on the use of more highly modified asphalt binders to further reduce the impact of studded tire wear.

Fatigue Performance of High- and Low-Strength Repaired Welded Steel Joints

Large portions of infrastructure buildings, for example highway- and railway bridges, are steel constructions and reach the end of their service life, as a reason of an increase of traffic volume. As lifetime extension of a commonly used weld detail (transverse stiffener) of these structures, a validated approach for the weld repair was proposed in this study. For this, welded joints made of S355J2+N and S960QL steels were subjected to cyclic loading until a pre-determined crack depth was reached. The cracks were detected by non-destructive testing methods and repaired by removal of the material around the crack and re-welding with the gas metal arc welding (GMAW). Then, the specimens were subjected to cyclic loading again. The hardness, the weld geometry, and the residual stress state was investigated for both the original- and the repaired conditions. It was determined that nearly all repaired specimens reached at least the fatigue life of the original specimen.

Vibration of submerged floating tunnels under asynchronous support excitation

In recent years, submerged floating tunnels (SFT) have received considerable attention due to the growing increase of traffic volume and travel time. SFT provides eligible options for crossing long waterways. The long span of the SFT increases the probability of asynchronous excitation. This study examines the seismic behavior of the SFTs considering a) spatial variation of ground motion along the tunnel length, b) effect of different assumptions regarding this spatial variation, c) effect of of two- and three-dimensional modeling of fluid field. Two approaches including finite element and analytical solutions are used in the assessments. The results show that accounting for spatial variation of ground motion and three dimensionalities of the fluid field are detrimental in obtaining a realistic estimate of response parameters. Also, it is shown that using a linear approximation of spatial variation of ground motion along the tunnel length could give acceptable approximation of actual response.

Analysis and Evaluation of Ramp Metering: From Historical Evolution to the Application of New Algorithms and Engineering Principles

In the modern era, characterized by intense urbanization and frequent travel between interconnected communities, the constant expansion of cities, associated with high densities and growing need for traveling, has led to a significant increase in road traffic volumes. More than ever, road traffic today requires effort to be managed effectively in order to improve performance and safety conditions, given the greater probability of unpleasant events such as accidents or road congestion with related delays and the increased stress levels of the user and infrastructure. Fortunately, there are already various engineering tools, such as ramp metering, that can be used for this purpose. Ramp metering allows for achieving the aforementioned desired benefits, including improving mobility, reliability, efficiency, and safety, and even reducing environmental impact. It also has been shown to be cost-effective from the existing literature. Further research will be necessary to strengthen the quality, efficacy, and efficiency of ramp metering, especially considering the fast-paced progress in technology (e.g., connected autonomous vehicles and drones used for surveys) and new challenging scenarios (e.g., congested industrial areas and emergency vehicles). This review’s scope is to present a general overview of principal ramp metering solutions, focusing on current research studies in the last couple of years and highlighting some of the main algorithms used for this purpose, depending on diverse scenarios. With this article, the authors desire to present the subject of ramp metering, providing a general overview of its story, evolution, and recent analytical models.

Analysis of the Near-road Fine Particulate Exposure to Pedestrians at Varying Heights

ABSTRACT Scientific literature has overlooked how PM2.5 concentrations vary with varying pedestrian heights near a roadway. Understanding this is important because walking is an essential commuting element of a sustainable transportation system, and pedestrians’ height varies widely. Therefore, the focus of the current study is to bridge this gap using results from CALINE 4 model and mobile PM2.5 measurements. In CALINE 4, a simple pedestrian pathway depicting the selected study site located near the Sardar Patel Road, Chennai, India, was simulated. The PM2.5 concentrations were estimated on this pathway at varying heights (0.1–1.8 m) in 135 simulated runs. Subsequently, the sensitivity of the PM2.5 exposure difference across heights was explored with varying ambient PM2.5 concentrations, wind speed, traffic volume, and traffic compositions. Results indicated that the PM2.5 concentrations reduced with increasing heights of pedestrians in all the modelled runs. When this PM2.5 exposure difference was investigated with varying surrounding conditions, it was found that the difference in PM2.5 exposure across heights was influenced by the wind speed, traffic volume, and traffic composition. Ambient PM2.5 concentrations had no discernible effect on it. Car-dominated traffic with a higher mode share of heavy commercial vehicles was marked with the highest PM2.5 exposure difference across heights. For traffic volume, it was observed that for every 100 vehicles hr–1 increase in traffic volume, the PM2.5 exposure difference increased by 0.13 µg m–3 m–1 in the range of pedestrian’s height. For wind speed, calculations suggested that for every 1 m s–1 increase in wind speed, the PM2.5 exposure difference was reduced by 0.095 µg m–3 m–1 in the range of pedestrian’s height. Finally, to bolster the modelling results, mobile PM2.5 measurements (using portable, low-cost optical particle sensors) were conducted near a busy urban roadway at two different heights, 80 cm and 150 cm, during peak and off-peak hours. The results of mobile measurements were found to be consistent with CALINE 4 modelled results.

Assessment of tsunami evacuation road performance

A series of disasters, from the 2004 Aceh Tsunami to the 2009 Padang Earthquake, has changed the paradigm of urban development in coastal areas in Indonesia. District or City Regional Regulations concerning Regional Spatial Planning finally oblige disaster mitigation by constructing evacuation roads. The attraction of the Tsunami Evacuation Road (TES) which was built with a relatively wide size in the city, makes the road a favourite route for motorists. The increased vehicular traffic also triggered the addition of the number of new commercial buildings along the road. The Indonesian Road Capacity Manual 1997 for urban roads is used as a reference in the analysis of the service performance of these road sections. The relatively rapid increase in traffic volume and side-road disturbances have resulted in a relative decline in road performance in a short period. The active role of the government in minimizing body side disturbances, by maximizing the implementation of traffic management and control of land-use changes are options.

Introducing Free airspace, a way to solve Europe’s airspace capacity issues.

In the past decades aviation within Europe has continued to grow in volume. With the increase in volume, traffic delays have increased as a result of bottlenecks that originate from traffic flow design decisions made when European air traffic volumes were a lot smaller and delays were not of a major concern. In order to ease the strain on the situation a European wide solution has been developed known as the single European sky agreement. The idea of this agreement is to reduce airspace congestion and increase efficiency whilst utilizing the available capacity to its fullest. This led to the formulation of the following question: What potential solution could be formulated in order to accommodate the increases in traffic volume, lack of efficient use whilst taking into consideration the considerable number of hurdles that prevent such optimization. Further attention will be given in this article to the following topics which have a major influence on the efficiency and use of airspace in Europe. Functional airspace blocks (FAB’s) will be investigated in order to define what they are and how their use limits capacity in European airspace. The appropriateness of the use of “entry points’ to airspace sectors and consideration of alternative structures (systems). The benefits and disadvantages of routes (flying from waypoint to waypoint) versus flying direct routings (shortest great circle distance). Analysing the usage of standard instrument departures and standard terminal arrivals and what role they play in flight operation, and their influence on efficiency. The effects of topography, geopolitical and environmental variables on the factors described above. By answering these questions, the aim is to create a solution for European airspace capacity issues. As well as stimulating the debate on how the current issues can best be tackled and above all find a solution which decreases the number of delays, increases efficiency and by doing these things also reduces excess fuel burn and the unnecessary emission of carbon dioxide and other pollutants.

Analysis of Terminal Area Airspace Operation Status Based on Trajectory Characteristic Point Clustering

The terminal control area airspace system is one of the most complicated subsystems in the entire air traffic control system. With the continuous increase of air traffic volume, the utilization of its airspace resources has become a bottleneck restricting the sustainable development of the system. Monitor and obtain its operating status information and formulating corresponding mitigation measures are essential to improve the overall performance of the system. In order to achieve that, a new system analysis method based on clustering of trajectory characteristic point is proposed. The flight trajectories from radar position data are reconstructed at first. Followed by the method of extracting flight trajectory characteristic points including turning points, altitude transition points and speed adjustment points, all characteristic points are extracted. Then, K-means is applied for clustering according to their 3D space position, while the results are analyzed by introducing evaluation indexes based on air traffic control operation strategies. Numerical experiments show significant clustering characteristics and revealing the operation status of the terminal area airspace, which can help air traffic manager to identify defects in airspace operation and providing guidance for future airspace planning and flight procedure adjustment.

Determination of Passenger Car Unit for Urban Roads: A Case Study in Addis Ababa

In Ethiopia, specifically on Addis Ababa city roads operating, vehicles are mixed with varying static and dynamic traffic characteristics that are very challenging for the traffic analyst to come up with a sole solution to the traffic malady. Under heterogeneous traffic, each vehicle type cannot be compared with other vehicle types since it shows different effects on the road. It could be observed that the majority of the drivers in Addis Ababa road networks do not follow proper lane discipline to use any available space on the road sections. Currently, Ethiopia is using the passenger car unit values from other countries manual, which doesn't represent the local traffic and roadway conditions. This study was initiated to establish the PCU values that will cater the local settings. Hence, this study was focused on estimating the PCU values of multilane highways in Addis Ababa city and determining the influence of traffic volume and width of the road on the values of PCU. The PCUs were estimated for four vehicle types based on the variation of traffic volume and carriageway width. Dynamic PCU method was used to determine PCU values, and a linear regression analysis was performed for model development. The developed model is used to estimate PCU values having the same traffic conditions and roadway conditions found in other countries. The study results indicated that as the traffic volume and carriageway width increases, the passenger car unit value also increases. Also, it was found out that the results of PCU values in this study showed higher values than those provided in Highway Capacity Manual (HCM). Hence, the PCU values obtained are recommended to reflect the existing traffic condition in the locality.

Determination of Passenger Car Unit for Urban Roads: A Case Study in Addis Ababa

In Ethiopia, specifically on Addis Ababa city roads operating, vehicles are mixed with varying static and dynamic traffic characteristics that are very challenging for the traffic analyst to come up with a sole solution to the traffic malady. Under heterogeneous traffic, each vehicle type cannot be compared with other vehicle types since it shows different effects on the road. During the field observations, most of the drivers in Addis Ababa road networks did not follow proper lane discipline to use any available space on the road sections. Currently, Ethiopia is using the passenger car unit values from other countries' manuals, which don't represent the local traffic and roadway conditions. This study was initiated to establish the passenger car unit (pcu) to cater to the regional settings. Hence, the study's focus was to estimate the pcu values of multilane highways in Addis Ababa city and determine the influence of traffic volume and width of the road on the importance of pcu. The passenger car units were estimated for four vehicle types based on traffic volume and carriageway width variation. Dynamic PCU method was used to determine values and performed a Linear Regression analysis for model development. The developed model was used to estimate pcu values having the same traffic and roadway conditions in other countries. Results indicated that as the traffic volume and carriageway width increase, the passenger car unit also increases. Also, this study found out that pcu values were higher than those provided in Highway Capacity Manual. Hence, the pcu values obtained are recommended to reflect the existing traffic condition in the locality.

DEPARTURE TRAJECTORY OPTIMIZATION FOR NOISE ABATEMENT PROCEDURE IN SOEKARNO-HATTA INTERNATIONAL AIRPORT

Air traffic noise emission has been a growing concern for communities living within the vicinity of airports due to a massive increase in air traffic volume in recent years. This work focuses on the noise annoyance problem by optimizing one of the RNAV trajectories, which aims to minimize the noise footprint of a flying aircraft in a low altitude trajectory. Optimal control theory is applied to minimize the number of awakenings caused by a departing aircraft while constraining the relative increase of fuel consumption with regard to a fuel-minimal trajectory. The aircraft simulation model is based on the BADA 3 database, while the noise is modeled according to the ANP database, both published by EUROCONTROL. The methodology is demonstrated for the Soekarno-Hatta International Airport (CGK) in Jakarta; the result shows the comparison between fuel-minimal trajectories and noise-minimal trajectories for seven aircraft types representing the fleet mix at CGK. The number of awakenings of the noise-minimal trajectories is reduced by 30.33%, with an additional of 5% fuel consumption for the seven aircraft types when compared to the fuel-minimal trajectory.

ANALYSIS OF RISKS OF INTERNATIONAL ROAD CARGO TRANSPORTATION

The work was performed as part of the Crisis and Risks Engineering for Transport Services project of Erasmus+ program. Purpose. Nowadays the key role in ensuring business processes both within the state and in the performing of foreign economic activity belongs to the transport industry. Carriage of goods and passengers over relatively short distances is economically attractive for road transport, which has shown a significant increase of traffic volumes in recent years. At the same time, there are random factors and the resulting risks during international road transportation, which does not allow us to estimate the cost and duration of such delivery with sufficient accuracy. Therefore, the purpose of this work is to analyze the process of international cargo delivery by road and identify risks and reasons for their occurrence at each stage of transportation. Methodology. To achieve the goal of the work, the methods of statistical analysis were used to determine the volume and structure of foreign economic activity in the provision of transport services; methods of system analysis, including SWOT analysis, to determine the characteristic features and identify risks at the stages of international cargo transportation by road. Results. The analysis of the volume of foreign economic activity of Ukraine made it possible to establish that the European Union (EU) is its main foreign economic partner, and the transportation of 10% of goods by volume and 38% by value between that countries is carried out by road. Increasing the road transport part in foreign trade providing with the EU is also confirmed by the increase in the trucks number that crossing the western part of the Ukraine state border, especially the section adjacent to Poland. Using SWOT-analysis, the strengths and weaknesses, as well as risks and opportunities of international transportation of goods by road, are identified. Scientific novelty. It was found that the presence of a large number of participants in the transportation process and their possible incompetent actions lead to an increase in the number of random factors and the resulting risks. The authors identified transport risks and the reasons for their occurrence in the international road transportation. Practical significance. The obtained results can be used in the process of risk management to increase the efficiency of management of international cargo transportation by road.

Cellular automaton model for three-lane urban road considering Internet of Vehicles lane

Although the technology of Internet of Vehicles (IoV) is developing rapidly, it will still take a long time to realize its overall popularization. Aimed at this transition phase, this paper proposes to set up an IoV lane on the urban road, which is specially designed for the connected vehicles, to provide a better driving environment for the connected vehicles. Considering the operation characteristics of traffic flow under traditional and IoV environment, this paper establishes a three-lane cellular automata model for urban road traffic flow considering IoV lane, modified on the basis of the Modified Comfortable Driving (MCD) model and symmetric two-lane cellular automata (STCA) model, and then takes simulation by MATLAB and makes analysis. The result shows that the setting of IoV lane can improve the velocity of networked vehicles to a great extent with no or just a bit decline in the ordinary vehicles’ speed, and it has a great effect on the mixture traffic flow, including the increase in both traffic volume and the average speed. What’s more, when the networking proportion is between 0.2 and 0.76, and the space occupation ranges from 0.18 to 0.56, the traffic benefit of IoV special lane can reach the best.

Limited evidence for negative effects of highway widening on North American large mammals

Roads are one of the most severe threats to wildlife globally because of their pervasive and linear nature. Despite considerable attention afforded to road-effects on animals generally, little information is available concerning the specific impacts of road widening, also known as twinning or highway expansion. To address this gap, we monitored the abundance and distribution of large mammals adjacent to an 18-km section of highway in Ontario, Canada, that underwent expansion from a two-lane to a four-lane, divided highway, over 4 years. We expected to observe an initial decrease in large mammal track abundance and an increased distance from the highway, followed by a period of habituation during which track abundance and proximity to the highway would return to baseline levels. To quantify the effects of highway expansion, we monitored snow-tracks of three ungulates, two felids, and three canids on transects extending perpendicular and parallel to the highway. Our analyses revealed that proximity was species-specific and varied seasonally, but we found little evidence that the new four-lane highway alignment affected the movement ecology of large mammals in our study area. Limited increases in traffic volume could partially explain why we detected no change; however, traffic volume will rise. Although road widening is common for accommodating increased traffic volume, no studies have explicitly investigated its effects on animal movement ecology. Our findings suggest that increasing the footprint of existing roads, rather than building new roads, may be a suitable solution for accommodating increasing traffic with minimal impacts on adjacent large mammal communities.