Traffic Simulation Software VISSIM Research Articles

A study on the capacity assessment of turbo roundabouts and the applicability in Vietnam

A turbo roundabout (or Turbine) is an improvement from conventional roundabouts with lanes running in a spiral shape, helping vehicles to enter the intersection smoothly and eliminate conflicts, reducing traffic congestion as well as the risk of traffic accidents. The turbo roundabout is a modern intersection, newly developed around 1996, initially in the Netherlands, then expanded to many European countries, Russia, and North America. In Vietnam, this type of intersection is still a novelty and requires more scientific exploration. Based on research from developed countries and through the use of Vissim traffic simulation software, the paper presents an analysis and evaluation of the effectiveness of Turbo roundabouts compared to conventional roundabouts. The study also proposed and developed shifted exponential models, capable of well describing the nonlinear relationship between capacity of entry roadway with circular flow. Results show that the turbo roundabout is a potential solution for Vietnamese traffic. The study's evaluation using a basic layout of a two-lane turbo roundabout with only automobile traffic composition limits its applicability to mixed traffic environments. Initially, the study proposes the installation of turbo roundabouts on access roads of freeways, or motor highways with low-to-medium traffic volume

Study of Urban Arterial Road Off-Ramp Configuration in Highway Municipal Reconstruction

To reduce traffic congestion and improve the overall traffic capacity of roads, the municipal reconstruction of arterial roads from high-grade highways often involves setting up auxiliary roads on both sides of the road. This paper analyzes the existing methods of determining the configuration of urban arterial road off-ramps and proposes a novel design method, includes adding a “waiting for merging” section. Based on the traffic flow characteristics of the main roads, auxiliary roads, as well as off-ramps, second-stage deceleration theory and the insertable gap theory are applied. Considering the worst-case of diverted vehicles, a calculation model for the length of the urban arterial road off-ramps is proposed and utilized to calculate the advisory values for each segment of the off-ramps. Taking the reconstruction of an expressway in Hubei Province, China, as a case study, Vissim traffic simulation software was used to compare the proposed method with the traditional design method under four different traffic volumes. The results show that the proposed design method greatly improves the overall traffic capacity of roads compared with the traditional method, with a reduction of approximately 40% and 60% in delay time and queue length for the overall traffic, respectively. Furthermore, the research results can provide direct and effective design solutions and a basis for decision-making for setting the length of main and auxiliary road off-ramps.

A simulation based comparative analysis of interconnected signalized intersections and roundabouts from the aspect of permeability

The utilization of the tools provided by digitalization became increasingly important for the micro-level modelling of road traffic, since it typically takes the form of a highly dynamic system. In the publication, the PTV Vissim traffic simulation software is used for the modelling of such a system, a traffic junction formed by two interconnected signalized intersections. The first goal of the analysis was to reveal how the optimization of the signal program in a specific way affects the operation of the entire system in terms of throughput during peak periods. After that, the possibility of modelling the same traffic junction with roundabouts was also explored. Finally, the results for the total traffic throughput of the system during the peak periods were compared in case of the different model variants. The resulting comparison present the permeability variation in a well-structured way and could also provide a useful example for the field.

Analysis of traffic flow due to lane changes by heavy vehicles

The transportation of goods via heavy vehicles (HV) plays a crucial role in urban economics. However, the operational and physical characteristics of these vehicles negatively impact traffic flow, leading to reduced speeds and increased congestion. This study examines the influence of HV lane changes on average traffic speed by implementing diverse lane change intensities and alternative strategies that restrict HV to specific lanes, narrowing their lane-changing space. Five HV classes based on axle count were analyzed using Vissim traffic simulation software on a 600 m JORR toll road segment. Three strategies were assessed across various scenarios, with differing HV composition percentages. Results show that HV lane changes, simulated using Vissim, significantly affect average traffic speed. Comparing high and low-intensity lane changes revealed an approximately 12% speed increase. Additionally, every 5% increment in HV composition led to an average 3% traffic speed reduction. In high-density conditions for every 5% increase in the composition of HV from high-intensity compared to medium and low-intensity lane changes, the average speed of traffic flow increases by 4% and 8% in low-density conditions. This research highlights the importance of enforcing designated lane usage for HV on toll roads to enhance traffic flow performance.

An Incident Detection Model Using Random Forest Classifier

Traffic incidents have adverse effects on traffic operations, safety, and the economy. Efficient Automatic Incident Detection (AID) systems are crucial for timely and accurate incident detection. This paper develops a realistic AID model using the Random Forest (RF), which is a machine learning technique. The model is trained and tested on simulated data from VISSIM traffic simulation software. The model considers the variations in four critical factors: congestion levels, incident severity, incident location, and detector distance. Comparative evaluation with existing AID models, in the literature, demonstrates the superiority of the developed model, exhibiting higher Detection Rate (DR), lower Mean Time to Detect (MTTD), and lower False Alarm Rate (FAR). During training, the RF model achieved a DR of 96.97%, MTTD of 1.05 min, and FAR of 0.62%. During testing, it achieved a DR of 100%, MTTD of 1.17 min, and FAR of 0.862%. Findings indicate that detecting minor incidents during low traffic volumes is challenging. FAR decreases with the increase in Demand to Capacity ratio (D/C), while MTTD increases with D/C. Higher incident severity leads to lower MTTD values, while greater distance between an incident and upstream detector has the opposite effect. The FAR is inversely proportional to the incident’s location from the upstream detector, while being directly proportional to the distance between detectors. Larger detector spacings result in longer detection times.

Control Method for Connecting the Elevated Expressway with the Ground Intersection Based on Reflective Film Material Guidance

With the rapid development of elevated expressways, urban elevated expressways bear more and more traffic volume, and the adoption of environmental protection materials has become an inevitable trend in the development of elevated expressways. a control method for connecting the elevated expressway with the ground intersection based on reflective film material is presented. Firstly, the green reflective film material is used to guide the connecting section of the elevated expressway and the ground intersection. Then, the corresponding signal timing method is proposed to optimize the traffic flow time between the elevated expressway and the ground intersection.Finally, through the analysis of the VISSIM traffic simulation software to evaluate the results show that the method is based on the reflective film material can effectively guide the elevated expressway with the ground intersection connection section, under the premise by signal optimization technology to further improve the traffic efficiency, effectively reduces the overhead elevated expressway with the ground intersection connection number of the conflicts, It provides a basis for the research on the connection section between the elevated expressway and the ground intersection based on reflective film material guidance.

Are facilities to support alternative modes effective in reducing congestion?: Modeling the effect of heterogeneous traffic conditions on vehicle delay at intersections

Multimodal facilities are being built in a majority of urban areas to accommodate both motorized and non-motorized traffic. The resulting transportation system is susceptible to complex interactions between different modes and users. These complex interactions are hard to quantify and capture on a regular basis. There is a need to rely on a microsimulation platform to replicate such real-world scenarios and forecast future conditions. This study focuses on assessing the effect of heterogeneous traffic conditions involving multiple modes like light rail transit (LRT), walking, bicycling, and motorized traffic on vehicle delay at intersections using Vissim traffic simulation software. A 2.5-mile urban arterial corridor comprising of seven at-grade and two grade-separated signalized intersections along US-29 route in the city of Charlotte, NC, USA was chosen for analysis and modeling. Base simulation model was developed by replicating the traffic scenario for the year 2018 (without LRT and non-motorized traffic). External controllers like VisVAP and Viswalk were used to assign signal priority and model heterogenous traffic conditions. The vehicle operational performance of the corridor improved along the major street after the addition of the LRT. An increase in vehicle delay on the major street was observed with an increase in the non-motorized traffic. Contrarily, the operational performance of the cross-streets at at-grade intersections did not see any significant change due to the addition of non-motorized traffic. The proposed framework assists planners to assess the impact of adding a new transit system like LRT and associated non-motorized traffic on the urban corridor.

An adaptive timing mechanism for urban traffic pre-signal based on hybrid exploration strategy to improve double deep Q network

With the increasing traffic congestion in cities, the priority of public transit has become a consensus for the development and management of urban transportation. The traffic pre-signal mechanism, which gives priority in time and space to buses by optimizing road right-of-way allocation, has gained wide attention and application. In order to broaden the action exploration range of the agent and avoid the pre-signal decision from falling into suboptimal strategy or local optimal strategy. For the exploration strategy of the DDQN algorithm, this paper reduces the probability of directly selecting the local optimal action and increases the probability of selecting non-greedy actions based on the principle that “the action with a larger value function is more likely to be selected.” This paper addresses the problem that the existing urban traffic pre-signal mechanism cannot adaptively adjust the advance time, and proposes a traffic pre-signal adaptive timing mechanism based on a Hybrid Exploration Strategy Double Deep Q Network (HES-DDQN) by combining the epsilon -greedy strategy and Boltzmann strategy. We have used the traffic simulation software VISSIM to conduct simulation experiments on an intersection. The experimental results show that, compared with the method of setting no pre-signal and the formula method of setting pre-signal, the HES-DDQN pre-signal mechanism can significantly reduce the average delay of buses, the waiting queue length, and the number of stops of social vehicles.

Influential Factors and Determination Method of Unconventional Outside Left-Turn Lanes Based on a BP Neural Network

To reduce the delay caused by the interweaving and parallel driving of multiple left-turn vehicles and through vehicles upstream of the intersection entrance, the influencing factors and determination methods of unconventional left-turn lanes are studied in right-hand traffic (RHT) countries. For countries driving right, left-turn lanes are usually on the inside of roads. However, when there are a large number of vehicles turning left in the outer lane of the upstream section of the intersection, these vehicles will be forced to pass many consecutive parallel lanes and then enter the left-turn lane. During this process, many traffic conflicts will occur between left-turning vehicles and going-straight vehicles, which will lead to longer traffic delays. To reduce traffic conflicts and delays caused by problems mentioned before, a scheme of setting left-turn lanes abroad is proposed, and major influencing factors and judgment methods of such a scheme are also studied. With the help of traffic simulation software VISSIM, the simulation model of intersection entrance with a different number of through lanes, length of weaving section and left turn inner and outer lanes is established. By inputting different numbers of entry through vehicles and left-turning vehicles in the outer lane, the delay data under different geometric and traffic conditions are obtained for simulation analysis. With the help of MATLAB software, this paper analyzes the influence of the length of the weaving area and the number of left-turning vehicles on the delay of inside and outside left-turning lanes under the condition of a different number of straight vehicles, as well as the variation law between them. By inputting parameters such as the length of the weaving area and the number of lanes, go-straight vehicles and left-turning vehicles into the system of VISSIM, a BP neural network model is constructed and trained. When investigating the entrances of four intersections, the BP neural network model is used to analyze and calculate the traffic delay and determine the setting scheme of the inside or outside of the left-turn lane. Through experiments and further studies, a phenomenon was found: When more vehicles chose to turn left or go straight in the outside lane, the length of the weaving area will become shorter, and the delay reduction effect of the unconventional left-turn lane will more obvious. The specific location of the left-turn lane should be determined by the constructed BP neural network model through the comparative analysis of delay, and the judgment results are in good agreement with the realistic scheme.

Evaluation of Intersection Properties Using MARS Method for Improving Urban Traffic Performance: Case Study of Tekirdağ, Turkey

Increasing urban traffic performance is a technical problem that has been investigated by many researchers these days. Traffic performance can be increased in many ways, as part of the transportation planning process, on smaller scales, or with different methods and techniques. The determination of traffic intervention areas in urban transportation planning is an intervention type that determines the rate at which the traffic performance will increase. Although transportation planning is an integrated issue, the type of traffic modification and prior intervention on intersections are often determined with partitive paradigms and strategies. It is a significant opportunity for decision makers to be informed in advance of the effects of intersection characteristics on the overall traffic performance. However, it is not an attempted or tested concept to perform a general assessment of the impact of the intersection characteristics on the overall performance of the intersections. In this study, a four-stage integrated analysis including the multivariate adaptive regression splines (MARS) method is proposed for the overall traffic performance evaluation. The traffic characteristics of intersections are first indexed and categorized. The intersection performance results are then obtained using the VISSIM traffic simulation software. Subsequently, the relationship between them is determined with the MARS method, and the effects of the intersection characteristics on the traffic performance are investigated. Tekirdağ, a metropolitan city located in northwestern Turkey, is selected for the case study. According to the obtained simulation results, the suggestions related to the development of intersection performances are made and tested.

Signal timing optimization design of cross intersection-- A Case study of The intersection of Minzhu South Road and Fengshou Road in Jiaozuo City

The capacity of intersection affects the maximum capacity of road to a certain extent. The traffic capacity of the intersection can be improved to some extent by optimizing and adjusting the parameters of the signal timing model. Taking the cross-type intersection at the intersection of Minzhu South Road and Fengshou Road in Jiaozuo City as the research background, this study optimizes the signal timing design for the current intersection, optimizes the signal timing design by using Webster algorithm, and conducts simulation by using traffic simulation software VISSIM. The results showed that the average delay at the intersection was reduced by nearly seven seconds.

Design of On-line Simulation System for Signal Control of Urban Intersections Based on Visual Sensing Technology

Intersection area is the area with the most serious conflicts and accidents in the whole urban traffic system. Therefore, it is of great significance to combine modern computer technology, sensing technology and communication technology to intelligently control intersections, improve the efficiency of traffic signal control and reduce the delay time in conflict areas. Starting with video detection and using deep learning in the detection module, a video detection mechanism based on restricted Boltzmann machine network is proposed. Based on C # programming language, the intersection traffic signal simulation module is designed through COM interface provided by traffic simulation software VISSIM, which realizes road network import, parameter setting, signal timing change, simulation operation and simulation result output. Numerical experiments show that fuzzy control method with self-correcting factor is superior to timing control method and classical fuzzy control method in average delay time of vehicles.

Assessing the Environmental and Economic Footprint of Electronic Toll Collection Lanes: A Simulation Study

Electronic toll collection (ETC) plays, as part of transport demand management (TDM) measures, an important role in preventing traffic congestion and improving the environmental conditions in urban and rural areas. An attempt is made in the framework of this paper to evaluate the overall performance of a toll station when a lane is dedicated to ETC. The case study refers to a toll station in the Thessaloniki Metropolitan Area, Greece. Scenarios considered specific traffic characteristics, variable toll booth setups, and different penetration rates of the ETC tag users for car and heavy vehicles. The tool used in the evaluation process was the PTV Vissim traffic simulation software. The operation of the toll station during a specific peak-hour period was simulated with the aid of the specific software. In total, 39 alternative scenarios were developed and compared to determine the level of penetration rate for which the ETC lane would be effective for different toll booth setups. Results showed that when the right lane of the toll station is converted to ETC lane, the penetration rate of this lane must be greater the 15% for the private vehicles and 20% for the heavy goods vehicles (HGV) to reduce traffic congestion and to improve environmental conditions. It was also found that when an additional ETC lane was introduced to the existing toll station set up, traffic congestion and the associated environmental conditions were much improved even for low penetration rates. It must be noticed that the results from the use of discounted cash flow methods like internal rate of return (IRR), net present value (NPV) and benefit–cost ratio (BCR) showed that all economic indicators converge as penetration rate increases in all toll booth setups. Therefore, there is a specific penetration rate threshold above which the economic viability of the investment is secured. These findings can assist the design of an effective policy in terms of the optimized operation of a toll station and sustainable mobility planning.

Environmental Adaptive Urban Traffic Signal Control Based on Reinforcement Learning Algorithm

Urban traffic signal control is an important part of the construction of intelligent regional traffic. Aiming at the problem of the optimal control strategy in urban traffic signals, this paper proposes environmental adaptive urban traffic signal control based on reinforcement learning algorithms. Through the continuous perception of the traffic environment, the position and speed of the vehicles in different environments are expressed in a matrix, and the parameters are continuously iteratively optimized through the reinforcement learning method to optimize the objective function (the vehicle that can pass the most in a limited time) to achieve the purpose of effective vehicle control. According to the traffic simulation software Vissim, it can be known that the algorithm proposed in this paper performs better in terms of average waiting queue length and global average speed compared with other algorithms, and the deep learning algorithm is significantly better than other algorithms in terms of stability. The average speed of the deep learning algorithm is increased by 9% compared with the baseline, and the average waiting queue length is reduced by 13.4% compared with the baseline. The experiments studied this time are sufficient to prove that the algorithm in this paper can adapt to the dynamically changing and complex urban traffic environment and has great research value.

Coordinated Control Method for Trams on Urban Arterial

To improve the operation efficiency of the trams on the arterial, a green-wave coordinated control scheduling method for trams at intersections is proposed. The influence of the tram on the green wave programming model is analyzed, and the calculation formula of the intersection distance in the programming model is amended. Tram priority signal control system is introduced, including the absolute priority and the relative priority. Combined with these two priority schemes, according to the type of intersection and the time when the tram arrives at the intersection, the tram priority control strategy is designed. Then the position of the tram detector is studied. According to the regularity of tram’s operation, the appropriate interval between the departure times of trams is proposed to prevent multiple trams arriving within the same traffic signal period. Finally, the microscopic traffic simulation software VISSIM is used to establish the coordination control model of the tram line in Huaian city, in order to validate the proposed method.

Identification of Effective Intersection Control Strategies During Peak Hours

Traffic congestion during peak hours is one of the major issues in developing countries like Sri Lanka. Drivers undergo a considerable delay during the peak hours especially in the city centres. There are several identified reasons for the congestion. Among them ineffective intersection control strategy used is one of the major causes. There are several levels of intersection controls available. In case of Sri Lanka during the peak hours most of the intersections in city centres are controlled by traffic police in major intersections and in some extreme traffic conditions grade separated intersections also provided. When the traffic police officers control the intersection, they mostly use the queue clearing approach. In such case their preference will be on the major road movements and lesser preference will be given to the minor road movements. This study tried to find out the effectiveness of the manual control by traffic police officers compare to traffic signals. Four Junctions which are controlled by Traffic police officers during the peak hours selected for the analysis. Traffic micro simulation software VISSIM has been used for the analysis and it has been calibrated and validated to local conditions before using it for the analysis. Junctions were modelled for the traffic police phase arrangement and cycle time, and for a designed traffic signal time. When the junction is undersaturated traffic signals gives lesser delay than traffic police officers control. When the junction is oversaturated traffic police officers become effective because they allow risky merging movements to reduce the critical flows.

Coordinated control method of intersection traffic light in one-way road based on V2X

One-way roads have potential for improving vehicle speed and reducing traffic delay. Suffering from dense road network, most of adjacent intersections' distance on one-way roads becomes relatively close, which makes isolated control of intersections inefficient in this scene. Thus, it is significant to develop coordinated control of multiple intersection signals on the one-way roads. This paper proposes a signal coordination control method that is suitable for one-way arterial roads. This method uses the cooperation technology of the vehicle infrastructure to collect intersection traffic information and share information among the intersections. Adaptive signal control system is adopted for each intersection in the coordination system, and the green light time is adjusted in real time based on the number of vehicles in queue. The offset and clearance time can be calculated according to the real-time traffic volume. The proposed method was verified with simulation results by VISSiM traffic simulation software. The results compared with other methods show that the coordinated control method proposed in this paper can effectively reduce the average delay of vehicles on the arterial roads and improve the traffic efficiency.

Modified Traffic Flow Model with Connected Vehicle Microscopic Data for Proactive Variable Speed Limit Control

Most previous prediction based Variable Speed Limit (VSL) control strategies focused on improving traffic mobility based on the macroscopic traffic data. Nowadays, the emerging technologies provide access to the microscopic traffic flow data, which better captures the details of traffic flow dynamics in the VSL controlled environment. Thus, in this paper, the microscopic traffic flow data were utilized as a supplement to predict the evolutions of traffic flow parameters. The proposed VSL control algorithm adopts the Model Predictive Control (MPC) framework, which employs a modified version of the classic traffic flow model METANET to take advantage of the microscopic data in traffic flow predictions. The microscopic traffic simulation software VISSIM was used to establish an experimental simulation platform and perform real time traffic responsive control based on field data. The proposed control strategy was evaluated against the no-VSL control and macroscopic-based VSL controlled scenario. The results show that utilizing the proposed modified METANET model reduced the error in speed prediction accuracy and improved system mobility performance.

A two-level identification model for selecting the coordination strategy for the urban arterial road based on fuzzy logic

A novel model for identifying the traffic condition of urban arterial roadways is proposed in this paper to improve the operational efficiency and safety of the urban traffic arterial road system. During the identification process, fuzzy analytic hierarchy process and fuzzy integrated evaluation are employed to identify the traffic condition on the arterial road; according to the fuzzy logic scheme, a proper coordination strategy is then generated based on the resulting identification of each way of the artery. To verify the effectiveness of the proposed method, a numerical experiment is carried out by using the microscopic traffic simulation software VISSIM, where a traffic flow simulation system is generated according to the real-time traffic data. The comparison results show that the proposed model works well to fit with the actual operating condition of the arterial traffic and the proposed coordination strategy can provide a better performance for the traffic management.

Effect of Detector Placement, Train and Traffic Characteristics on Operational Performance of At-Grade Railroad Crossing

This paper focuses on modeling and evaluating the effect of detector placement (distance), train, and traffic characteristics on operational performance of at-grade railroad crossings. Train and vehicular traffic related data were collected at an at-grade railroad crossing in the city of Charlotte, NC, USA. The collected data was then loaded into VISSIM traffic simulation software to develop a calibrated model and compute operational performance measures such as delay, the number of stops, and queue length. In addition, VISSIM traffic simulation software has an essential tool to place the detector on the track within a certain distance from the road. This tool was used to compute operational performance measures by detector placement (distance from the road). The results obtained by detector placement, the length of the train, speed of the train, and traffic volume are summarized. The findings help engineers and practitioners to place detectors on the track, within an ideal distance, for reducing delay and congestion without compromising on safety and flow of the traffic passing an at-grade railroad crossing.