Traffic Platoon Dispersion Modeling on Arterial Streets

Author(s):  
Abdelaziz Manar ◽  
Karsten G. Baass

Platoon dispersion is a key element in traffic simulation models designed to measure arrivals at traffic signals. One of the most popular models is contained in the TRANSYT program. In this program, dispersion is defined by the platoon dispersion factor, which is given for three types of conditions in relation to external friction. This study demonstrates that platoon dispersion depends not only on external friction but also on internal friction between vehicles in the platoon. As volumes and densities increase, platoon dispersion increases up to a maximum, which is attained at half the capacity. As volumes and densities increase further, dispersion decreases and reaches a minimum value at volumes around maximal capacity. Experimental analysis on eight arterial sites in the city of Montreal (Quebec, Canada) has confirmed this relationship between dispersion and traffic volumes. Mathematical models (having a parabolic shape) relating platoon dispersion to internal and external friction were developed for three different categories of arterial streets representing low, moderate, and heavy friction levels. These models could be introduced into signal coordination programs and could contribute to a better simulation of arriving platoons at intersections as volumes change in relation to time.

Author(s):  
Muhammad Tahmidul Haq ◽  
Amirarsalan Mehrara Molan ◽  
Khaled Ksaibati

This paper aims to advance the current research on the new super diverging diamond interchange (super DDI) design by evaluating the operational efficiency using real-world locations. As part of a comprehensive research effort on improving the performance of failing service interchanges in the mountain-plains region, the study identified three interchanges (Interstate 225 and Mississippi Avenue, Interstate 25 and 120th Avenue, and Interstate 25 and Hampden Avenue) at Denver, Colorado as the potential candidates to model for future retrofit. Four interchange designs (i.e., existing CDI [conventional diamond interchange], DDI, super DDI-1, and super DDI-2) were tested in this study. The operational analysis was conducted using VISSIM and Synchro. Several microsimulation models (120 scenarios with 600 runs in total) were created with three peak hours (a.m., noon, and p.m.) for existing (the year 2020) and projected (the year 2030) traffic volumes. The study considered two simulation networks: (1) when no adjacent traffic signal exists, to determine how the four interchange designs would perform if there were no adjacent signals or they were far away from the interchange; and (2) when there are two adjacent traffic signals, to evaluate the performance of the four interchanges in a bigger corridor with signal coordination needed. An important finding is that super DDI designs outperformed DDI with adjacent signals and higher traffic demand, while DDI performed similarly to or sometimes insignificantly better than super DDI if no adjacent intersections were located in the vicinity and if the demand was lower than the DDI’s capacity.


2019 ◽  
Vol 5 (9) ◽  
pp. 2029-2040 ◽  
Author(s):  
Ghufraan Mohammed Aboud ◽  
Areej Muhy Abdulwahab ◽  
Qais Sahib Banyhussan ◽  
Hamsa Abbas Zubaidi

Roundabouts are progressively being utilized on occupied arterial streets for traffic quieting purposes. Be that as it may, on the off chance that one indirect leg is close to a conveyance center point, for instance, stopping territories of strip malls, the passage traffic volumes will be especially high in pinnacle hours. On the basis of the Al-Turkman Roundabout, which is one of the most important roundabouts in Baghdad city, linking the areas of east of Baghdad to the city center in the area of Bab Al-Moatham. This area is characterized by its high traffic volumes (congestion), especially at peak periods causing a low level of service (LOS) with increased travel time delay, costs, and CO2 emissions. The research relied on the use of the SIDRA software to assess these variables by collecting traffic volumes in this area. The research proposed a series of planning procedures which are divided according to serial time scales. These planning procedures are to address the problem of congestion and traffic jams in the area, improve the level of service, and reduce travel time, cost and CO2 emissions. The research concluded that the application of the planning proposals in the study area has improved the level of service from E and F to C, reduced travel time by 16%, reduced costs by 25% and reduced CO2 emissions by 29%.


1970 ◽  
Vol 24 (3) ◽  
pp. 231-241
Author(s):  
Dražen Cvitanić ◽  
Deana Breški ◽  
Ivan Lovrić

The paper presents a comparison of the possibility and complexity of the calibration process of two microsimulation models. The first model CORSIM is simple for use while the second named S-Paramics is more complex software. For research purposes, a model of street network with defined geometry (number, width and purpose of lanes) has been made. The volume and distribution of traffic as well as the data about traffic signals were input in the models. Numerous simulations were performed, first with the default parameters of models, and then with the calibrated parameters. Both programs have resulted in very good prediction of the intersection capacity and discharge volumes. However, for the calibration of speed more time and effort have been made in S-Paramics in which the average speed may be higher than the defined free-flow speed. This can present a problem in determining the level of service and comparing the S-Paramics results with other simulation models and analytical method results. On the other hand S-Paramics has greater capabilities than CORSIM (roundabouts modelling, dynamic traffic assignment, opportunity to interact with traffic signals...). Thus, for each specific task, one should carefully choose an appropriate program which would result in necessary and reliable output data with minimum effort and time consumed.


2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Yun Bai ◽  
Jiajie Li ◽  
Tang Li ◽  
Lingling Yang ◽  
Chenxi Lyu

Prioritizing traffic signals for trams crossing intersections without stops can increase the service punctuality and travel speed of trams, but it may also increase the delays of other vehicles at intersections. This paper presents a model on coordinated control of traffic signals among successive intersections along the tramline, taking into account driving characteristics of trams and vehicles. The objective is maximizing the valid bandwidth of vehicle green wave to reduce vehicle delays, while the trams cross intersections without stops. Linear Interactive and General Optimizer (LINGO) is applied to solve the proposed model and VISSIM simulation software is adopted to assess the solutions attained by the proposed model and the previous TRAMBAND model. Case studies show that the solutions given by the proposed model facilitate trams to go through all intersections along the tramline without stops. In comparison with the TRAMBAND model, the proposed model reduces tram delay by 13.14 s/pcu and increases the throughput of vehicles at intersections by 4.45% and reduces vehicle delays by 2.22%. Extensive simulations have verified that the performance of the proposed model is stable under different tram headways, dwell time, and traffic volumes. It is also found that the tram headway must be multiple of traffic signal cycle time to completely realize green wave control of all trams at all intersections along the tramline.


2021 ◽  
Vol 11 (1) ◽  
pp. 365-376
Author(s):  
Andrzej Bąkowski ◽  
Leszek Radziszewski

Abstract The study analyzed the parameters of vehicle traffic and noise on the national road in the section in the city from 2011 to 2016. In 2013–2014 this road was reconstructed. It was found that in most cases, the distribution of the tested variable was not normal. The median and selected percentiles of vehicle traffic parameters and noise were examined. The variability and type A uncertainty of the results were described and evaluated. The results obtained for the data recorded on working and non-working days were compared. The vehicle cumulative speed distributions, for two-way four-lane road segments in both directions were analyzed. A mathematical model of normalized traffic flow has been proposed. Fit factor R2 of the proposed equations to the experimental data for passenger vehicles ranges from 0.93 to 0.99. It has been shown that two years after the road reconstruction, the median noise level did not increase even though traffic volumes and vehicle speeds increased. The Cnossos noise model was validated for data recorded over a period of 6 years. A very good agreement of the medians determined according to the Cnossos-EU model and the measured ones was obtained. It should be noted, however, that for the other analyzed percentiles, e.g. 95%, the discrepancies are larger.


2018 ◽  
Vol 11 (1) ◽  
pp. 1
Author(s):  
Supiyono, Dwi Ratnaningsih, Rudy Ariyanto

Abstract Highway in Malang there that needs to be analyzed is Intersections Letjend S. Parman Street – Ciliwung Street and Letjend Sutoyo Street – Letjend Selorejo. The road is an arterial road in the city of Malang with a high vehicle density level (Saputra, 2013). The Street was a high traffic flow led to queues or long saturated flow that is not supported by the settings of the light signals in accordance with the conditions in the field so often causes congestion. From finding a solution the traffic density in the study Letjend S Parman Street – Ciliwung Street and Letjend Sutoyo Street – Letjend Selorejo with Indonesia Highway Capasity Manual (IHCM). After stages 3-signal coordination calculation in Ciliwung Intersection of Malang, Intersection obtained time peak hours at the intersection area occurred at 11.00 – 12.00 GMT. Performance 3-waay junction on the Ciliwung Malang at this time has not met the target. Seen from there is still a Degree of Saturation (DS) which do not meet the targets ( ≤ 0,75), namely 0,83. After having don e engineering into 3 phases and cycle time 100 minutes Degree of Saturation (DS) be 0,77. Keywords: intersection, peak hours, capacity and degree saturation


2019 ◽  
Vol 8 (6) ◽  
Author(s):  
Polina A. Buyvol ◽  
Gulnara A. Yakupova ◽  
Irina V. Makarova

The transport system plays an important role in human activities and is an integral part of the successful functioning of the urbanized area. The increasing degree of provision of urban residents with transport services should at the same time keep the environment environmentally friendly and sustainable over time. The article is devoted to the issues of ensuring the rational functioning of the city transport system based on the development and implementation of an intelligent road infrastructure management system, the intellectual core of which are simulation models of problem areas of the road network. The objective of the study is the development of tools for organizing traffic in the conditions of the rapid growth of the fleet of vehicles. Research tasks were to analyze the research in the field of traffic management, to consider methods to reduce and prevent traffic jams on roads in general and in individual sections in particular. The following research methods were used: methods of system analysis, methods of modeling traffic flows, simulation, computer experiment. Achievements: the developed simulation model can be used to conduct a computer experiment in order to select the optimal parameters for the functioning of traffic lights on a specific section of the road network of the city of Naberezhnye Chelny


1997 ◽  
Vol 1572 (1) ◽  
pp. 105-111 ◽  
Author(s):  
Nagui M. Rouphail ◽  
Mohammad Anwar ◽  
Daniel B. Fambro ◽  
Paul Sloup ◽  
Cesar E. Perez

One limitation of the Highway Capacity Manual (HCM) model for estimating delay at signalized intersections is its inadequate treatment of vehicle-actuated traffic signals. For example, the current delay model uses a single adjustment for all types of actuated control and is not sensitive to changes in actuated controller settings. The objective in this paper was to use TRAF-NETSIM and field data to evaluate a generalized delay model developed to overcome some of these deficiencies. NETSIM was used to estimate delay at an isolated intersection under actuated control, and the delay values obtained from NETSIM were then compared with those estimated by the generalized delay model. In addition, field data were collected from sites in North Carolina, and delays observed in the field were compared with those estimated by the generalized delay model. The delays estimated by the generalized model were comparable with the delays estimated by NETSIM. The data compared favorably for degrees of saturation of less than 0.8. However, at higher degrees of saturation, the generalized model produced delays that were higher than NETSIM’s. Some possible explanations for this discrepancy are discussed. The delays estimated by the generalized model were comparable with delays observed in the field. Researchers have concluded that the generalized delay model is sensitive to changes in traffic volumes and vehicle-actuated controller settings and that the generalized delay model is much improved over the current HCM model in estimating delay at vehicle-actuated traffic signals.


Author(s):  
Michael Adamson ◽  
Grant G. Schultz ◽  
Mitsuru Saito ◽  
Michael D. Stevens

The purpose of this research was to evaluate the interaction of left-turn and opposing through traffic volumes for permitted and protected left-turn phasing at intersections and develop boundaries that help identify when to switch from permitted to protected phasing at signalized intersections. Permitted phasing allows vehicles to turn left after yielding to opposing vehicles; protected phasing provides an exclusive phase for vehicles to turn left without opposition; and protected-permitted phasing combines these phasing alternatives, allowing both permitted and protected turning movements. Intersections with 1, 2, and 3 opposing-lane configurations with permitted and protected-permitted models (split into green times of 10, 15, and 20 s) were analyzed for a total of 12 simulation models. Each model was divided into 100–225 different volume scenarios, with incremental increases in left-turn and opposing volumes. By exporting trajectory files from VISSIM and importing these into the Surrogate Safety Assessment Model, crossing conflicts for each volume combination in each model were extracted. MATLAB was then used to create contour maps representing the number of crossing conflicts per hour associated with different combinations of left-turn and opposing volume. Basic decision boundaries were examined in each contour map. Statistical analysis software was used to perform a linear regression analysis on transformed data and to develop natural log-based equations that form the decision boundaries for each configuration and phase alternative. These equations were graphed and final decision boundaries developed for the 1-, 2-, and 3-lane configurations between permitted and protected-permitted phasing as well as between protected-permitted and protected phasing.


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