Evaluation-of Traffic Flow and Traffic Network Management.pdf

Amman city, the capital of Jordan has suffered from the impacts of highway mode of transportation. Traffic network management system aim to reduce traffic congestion, delay, fuel consumption, and air and noise pollution. Also, to improve the level of service (LOS) of the urban streets and intersections. This research paper is an engineering project management study; it is about improving traffic network management system in Al Shmesani district in Amman. It was conducted on a network of two main arterials with eight signalized intersections. They are Al Kindi street continued with Prince Shaker Bin Zaid street and Al Sharif Naser Bin Jamel street. The traffic data was collected from the government records at several departments in Amman Municipality and Directorate of Public Security. Highway Capacity Software HCS2000 and updated Synchro-8 programs software were used to evaluate the traffic conditions at each intersection for years 2012 and 2022. The evaluation shows that the intersections are operating at LOS F with high delay time and high saturation flow. Two alternatives were used to improve the traffic conditions. The first one is to change the existing timing plan of the traffic signal to optimize timing plan, this showed little improvement in traffic condition. The second alternatives are to modify the geometric conditions with changing and optimizing the timing plan of the signalized intersections. It showed good improving in the traffic conditions and saving in delay time and fuel consumption at the existing and the future conditions. The Level of Service LOS's of the intersections were improved from LOS F to LOS C, D and E. It showed also the average overall saving in vehicle delay is about 87.75% and the saturation flow is improved at all intersections to less than one. The fuel consumption is also reduced with about 93%.

The main objective of this study is to evaluate and improve the traffic operations at the signalized intersections in Amman city in Jordan. Wadi-Saqra signalized intersection was chosen for this study. This intersection is located in the western central part of Amman the capital of Jordan. It has heavy traffic volume, with higher delay and heavy congestion traffic more than any other similar intersections in Amman. In this study, the intersection is analyzed as an isolated signalized intersection by using HCM (Highway Capacity Manual) and HCS (Highway Capacity System) computer program. Synchro computer program is also used for improvement through optimization process. The geometric, traffic and signalized data were collected during the morning and afternoon peak time periods. The results indicated that the current delay is 473 sec/veh with Level of Service F (LOS-F). Four alternatives are recommended to solve the current and future problems. The recommended alternatives are: 1. Prohibit left turning at all approaches. 2. Optimization of the existing traffic signals. 3. Construct one through overpass for one direction. 4. Construct two overpasses or one overpass and tunnel for two directions. The first three alternatives will not be able to reduce the level of service significantly. On the other hand, the fourth alternative will reduce the level of service from LOS F with (473 sec/veh) delay to level of service LOS C with (27 sec/veh) delay and will change the cycle length from 190 seconds to 90 seconds. The estimated initial cost of constructing two overpasses is about thirty million Jordan Dinars JD with annual saving of more than eight million JD. If alternative four was selected to solve the existing situation the following advantages can be attained: reducing the congestion on the signalized intersection especially during peak hours, reducing the cost of traveling for the public, increasing the efficiency of the road network, increasing safety, reducing the maintenance cost of the roads, improving traffic flow and traffic operations, and reducing air pollution and preserving the environment.

Improvement of Traffic Efficiency for Intersections in Azzawiya City, 2022

The increase in traffic congestion and accidents at the intersections are serious problems in Azzawiya City, resulting in high operating costs, lost time, driver frustration, high fuel consumption, and high pollution emissions, as well as human and material losses due to accidents. Therefore, the major goal of this study is to use Sidra Intersections 7.0 software based on HCM 2016 methodology to improve traffic efficiency at four critical intersections in Azzawiya city. The evaluation of the selected intersections takes into account a wide range of factors, including traffic volumes, geometric characteristics, and findings of the related studies. The analysis results were used to propose measures to improve traffic efficiency in terms of capacity and safety. In this thesis, geometric adjustments, signal timing optimization, and change of control type were the primary measures used to achieve the research's objectives. Several solutions have been proposed to improve the existing condition of intersections. Using the optimum signal timing combined with implementing some geometric adjustments, the LOS for Omar Al-Mukhtar intersection (signalized) improved from F to E, and the control delay decreased from 105.6 to 78.5 sec/veh. Al-Ghardabiya intersection (signalized) showed a decrease in delay time from 121 sec/veh to 76.8 sec/veh and LOS improved from F to E by using the optimum signal timing combined with implementing some geometric adjustments. To improve safety condition, Shlaby intersection (sign-controlled) was converted to a signalized intersection, which resulted in a slight increase in control delay from 26.2 sec/veh to 31.1 sec/veh and improvement of the LOS from D to C. For Al-Rihanna intersection (roundabout), a proposal has been made to provide short entry and exit lanes for all of its legs by restricting vehicles from parking near and inside the roundabout, which resulted in an improvement in LOS from E to C and control delay decreased considerably from 44.4 to 15.7 sec/veh. Overall, the study findings revealed that the capacity and safety level of the intersections that located in the city center (Shlaby & Al-Rihanna) can be improved considerably by implementing some minor geometric and operational changes. However, these simple and low-cost alternatives are not sufficient for the signalized intersections that are located on thecoastal road (Omar Al-Mukhtar & Al-Ghardabiya). Other solutions that require higher costs and relatively longer time, such as changing the intersections category from an at-grade intersection to a grade-separated intersection or constructing a ring road around the city to relieve pressure on the section of the coastal road passing adjacent to the city center. Keywords: Capacity; Safety; Traffic Efficiency; SIDRA; HCM; At-Grade Intersections

IOP Conference Series: Materials Science and Engineering, 2019

The traffic management systems are implemented on a large scale during the last decades in urban areas due to their feature to optimize the traffic capacity, in a simultaneous and real time, not only at the individual junctions but also the entire city level. This is achieved through the short term predictions, using the traffic data bases collected by the specific sensors from the traffic controlled crossroads or from other places into the city street network, data that's used on-line in order to optimize the traffic lights cycles onto all the controlled crossroads. In this way it is accomplished a optimal capacity for a certain traffic volume over a period of time. Using this method good results are obtained considering the reduction of the fuel consumption and of the pollution level. Another result is the increasing of the average speed of vehicles and the decreasing waiting times on the crossroads, which is beneficial for both cars and public transport. The case study for the Pitesti city highlights these aspects and shows how the urban transport model could be used for quantifying the effects of implementing the traffic management systems. The paperwork summary regarding the public transportation is attached.

The main objective of this study is to evaluate and improve the traffic operations at the signalized intersections in Amman city in Jordan. Wadi-Saqra signalized intersection was chosen for this study. This intersection is located in the western central part of Amman the capital of Jordan. It has heavy traffic volume, with higher delay and heavy congestion traffic more than any other similar intersections in Amman. In this study, the intersection is analyzed as an isolated signalized intersection by using HCM (Highway Capacity Manual) and HCS (Highway Capacity System) computer program. Synchro computer program is also used for improvement through optimization process. The geometric, traffic and signalized data were collected during the morning and afternoon peak time periods. The results indicated that the current delay is 473 sec/veh with Level of Service F (LOS-F). Four alternatives are recommended to solve the current and future problems. The recommended alternatives are: 1. Prohibit left turning at all approaches. 2. Optimization of the existing traffic signals. 3. Construct one through overpass for one direction. 4. Construct two overpasses or one overpass and tunnel for two directions. The first three alternatives will not be able to reduce the level of service significantly. On the other hand, the fourth alternative will reduce the level of service from LOS F with (473 sec/veh) delay to level of service LOS C with (27 sec/veh) delay and will change the cycle length from 190 seconds to 90 seconds. The estimated initial cost of constructing two overpasses is about thirty million Jordan Dinars JD with annual saving of more than eight million JD. If alternative four was selected to solve the existing situation the following advantages can be attained: reducing the congestion on the signalized intersection especially during peak hours, reducing the cost of traveling for the public, increasing the efficiency of the road network, increasing safety, reducing the maintenance cost of the roads, improving traffic flow and traffic operations, and reducing air pollution and preserving the environment.

The main objective of this study is to evaluate and improve the traffic operations at the signalized intersections in Amman city in Jordan. Wadi-Saqra signalized intersection was chosen for this study. This intersection is located in the western central part of Amman the capital of Jordan. It has heavy traffic volume, with higher delay and heavy congestion traffic more than any other similar intersections in Amman. In this study, the intersection is analyzed as an isolated signalized intersection by using HCM (Highway Capacity Manual) and HCS (Highway Capacity System) computer program. Synchro computer program is also used for improvement through optimization process. The geometric, traffic and signalized data were collected during the morning and afternoon peak time periods. The results indicated that the current delay is 473 sec/veh with Level of Service F (LOS-F). Four alternatives are recommended to solve the current and future problems. The recommended alternatives are: 1. Prohibit left turning at all approaches. 2. Optimization of the existing traffic signals. 3. Construct one through overpass for one direction. 4. Construct two overpasses or one overpass and tunnel for two directions. The first three alternatives will not be able to reduce the level of service significantly. On the other hand, the fourth alternative will reduce the level of service from LOS F with (473 sec/veh) delay to level of service LOS C with (27 sec/veh) delay and will change the cycle length from 190 seconds to 90 seconds. The estimated initial cost of constructing two overpasses is about thirty million Jordan Dinars JD with annual saving of more than eight million JD. If alternative four was selected to solve the existing situation the following advantages can be attained: reducing the congestion on the signalized intersection especially during peak hours, reducing the cost of traveling for the public, increasing the efficiency of the road network, increasing safety, reducing the maintenance cost of the roads, improving traffic flow and traffic operations, and reducing air pollution and preserving the environment.

The primary objective of this study is to acquire an understanding of the current state-of-the-art of traffic signal control strategies at urban street systems. Control of traffic signals is by far the most common type of control at heavily trafficked intersections in urban areas. Inefficient use of the transportation system results when traffic signals are set without the aim of optimizing them. The byproducts of such situations include greater fuel consumption, increased vehicle emissions, increased travel time, higher accident rate, and less reliable services. Signalized intersections can be classified into three types: (a) an isolated intersection (b) an arterial street and (c) a network. For the analysis of isolated intersection capacity and performance, many analytical methods have been developed. The commonly used methods include the U.S. highway capacity manual (HCM); Webster's method; and the Australian method. Investigation of traffic signal upgrading strategies in the field can be expensive and time consuming. Unexpected and unnecessary congestion may result and cause negative citizen reaction. Thus, many efforts have been directed towards the development and use of software computer models to evaluate the impacts of various strategies for upgrading traffic signals in different operating control field. The methods that showed good promise to reach the desired goal are: the urban transportation systems analysis, UTCS, metods; the splits, cycle and offset optimization technique (SCOOT); and the Toronto methods. These methods represent new concepts which could enhance the state of the art in online control techniques.

2014

At present, traffic congestion problem in Dhaka city is getting worse day by day. This is due to the huge amount of flow from side approaches, illegal car parking, mismanagement of traffic signal etc. The main aim of this investigation is to assess and develop the traffic operations at the Science Laboratory-Elephant Road signalized intersections in Dhaka city. This intersection is located in the busiest portion of Dhaka. The intersection has heavy traffic volume with higher delay and heavy traffic congestion compare to any other similar intersections in Dhaka. In this study, the intersection is analyzed as an isolated signalized intersection by using VISSIM simulation computer program. VISSIM computer program is also used for improvement through optimization process. The geometric, traffic and signalized data were collected during peak time periods. Four alternatives are recommended to solve the current and future problems. The recommended alternatives are—1. Banning right turning at all approaches (this alternative has already been implemented), 2. Optimization of the existing traffic signals, 3. Construct one through overpass for one direction and 4. Construct two overpasses for two directions. The first two alternatives will not be able to improve the level of service significantly. In contrast, the third and fourth alternative will improve the level of service with low delay time. The estimated initial cost of constructing two overpasses is more than annual saving. However, third alternative will be more cost effective and adequate to resolve traffic congestion problem of that location. If alternative three was selected to solve the existing situation; it will beneficial by reducing the congestion on the signalized intersection especially during peak hours, reducing the cost of traveling, increasing the efficiency of the road network, increasing safety, improving traffic flow and traffic operations, and reducing air pollution and preserving the environment.

Delays represent one of the indirect costs in terms of frustration, loss of time and discomfort to the drivers. On the other hand, it represents a direct cost in terms of fuel consumption/wastage on road networks during idleness and inactivity. Extreme delay at signalized intersections reflects the incompetence in the signal timing because of consecutive signalized intersections on the particular site. The traffic parameters performance is not a feasible method or practice. Furthermore, one of the significant ways to improve the performance of the network is by coordinating traffic signal in intersections. This study was done to highlight the ability of improving the level of service (LOS) of four intersections; two of them with four legs and two with three legs as well as two roundabouts in Kuala Lumpur and Petaling Jaya using SIDRA software version 4.0. In addition, the study aims to compare the results between each peak hour in terms of percentage of change in the variables and the delay. Moreover, consideration of geometric delay should be taken into account when comparing delays in peak hours in the morning and the evening peak hours. The results obtained show that the morning period is better than the evening period for the value of delay, queue, journey time and speed that was obtained from practical measuring in the study area. The average reduction of delay in the study area before and after optimization of SIDRA software is from 3489 Sec to 1571 Sec in the morning period as well as 5093 Sec to 1663 Sec in the evening period. The percentage of reduction was about 45% and 33% -respectively.