Analysis Of Queuing Behavior Of Left-turn Reverse Variable Lanes Vehicles And Its Influence On Traffic Efficiency And Safety

With the rapid development of China’s economic construction,the living standards of residents continue to increase,the number of urban motor vehicles and the proportion of motorized trips continue to increase,the degree of urban traffic congestion continues to increase.Intersections are the key nodes of the urban road network.Whether different types of traffic flows can be converted safely and efficiently here has an important impact on the smooth operation of the road network.Therefore,solving the problem of congestion at road intersections is to solve the problem of urban important link in traffic congestion.Left-turn traffic flow has more conflict points at the intersection,which has a greater impact on the capacity of the intersection.However,relying only on conventional traffic management methods such as widening of intersections,setting up dedicated lanes and phases,and adjusting signal timing,sometimes they cannot effectively deal with the congestion at intersections.Therefore,some scholars have conducted related research on left-turn traffic organization,and some non-traditional traffic organization methods for left-turn traffic is presented and applied.As a non-traditional mode of traffic organization,left-turn reverse lanes have been applied in Wuhan,Jinan,Handan,and other places in China.This traffic organization method mainly uses variable lane and pre-signal setting technology.It can dynamically adjust the driving direction on a specific lane according to the traffic flow conditions in different periods,and control with the pre-signal,which partially alleviates part of the problem.Congestion at intersections with heavy left turn traffic.Due to the setting of the left-turn pre-signal and the left-turn reverse variable lane,the queuing behavior of left-turn vehicles at the intersection has changed.Different queuing behaviors also have different effects on traffic efficiency at the intersection;the increase leads to the risk that the number of traffic conflicts with oncoming and oncoming traffic increases when left-turning vehicles leave the intersection.Therefore,in order to regulate the driver’s queuing behavior and improve the traffic efficiency and safety at intersections.This thesis analyzes the behavior of left-turn reverse variable lanes,studies the effect of left-turn reverse variable lane queues on traffic efficiency and safety,and optimizes the design of left-turn reverse variable lanes.The main work is as follows:(1)Analysis and modeling of vehicle queuing behavior of left-turn reverse lanePerform statistical analysis on the 4040 group of survey samples to explore the queuing selection behavior of left-turn vehicles at the left-turn reverse variable-lane intersection.Finding out the relevant factors affecting the vehicle queuing behavior,summarize the queuing behavior of left-turn vehicles.In addition,comprehensively consider the main pre-signal parking.The key factors such as the length of the queue in front of the line,the length of the green light of the main pre-signal,and the number of traditional left-turn lanes model the behavior of left-turn vehicles in queuing.After data validation,the overall accuracy of the model reached 80.2%,indicating that the left-turn vehicle queuing behavior model predicts that the results are more accurate and consistent with the actual driver selection.(2)Influence of queuing behavior of left-turn reverse lanes on traffic efficiencyBased on the results of the survey of queuing behavior of vehicles in the left-turn reverse variable lane,the left-turn queuing behavior after setting up the reverse variable lane is analized,and the queuing behavior is classified according to the different queuing locations to find out that different queuing behaviors affect traffic capacity.The key factors of the delay at the intersection are to establish the capacity model and delay model of the left-turn lane at the intersection,and to study the effect of different queuing behaviors of left-turn vehicles on the traffic efficiency of the intersection.(3)The impact of queuing behavior of left-turn reverse lanes on traffic safetyThrough on-site observation and data statistics,analyze possible safety risks,summarize the causes of different risks,and use the on-site statistics as a basis to analyze traffic conflicts such as rear-end collisions,red lights,and illegal traffic lanes.Technology in-depth research and analysis.(4)Left turn reverse variable lane optimization designAccording to the above three aspects of research,the problems caused by the setting of the left-turn reverse variable lane are summarized.Suggestions for improvement are made from the spatial geometric design of the left-turn reverse variable lane and the design of the signal control scheme,and the corresponding optimized design scheme is proposed according to the actual road traffic needs.Simulation experiments are performed by VISSIM to evaluate the effects before and after optimization.Simulation results show that at low peaks,flat peaks,and peak times,the delay of intersection vehicles under the dynamic control scheme is reduced by 6.7%,12.5%,and 16.1%,respectively,compared with the timing control scheme,and the overall operating efficiency of the intersection is improved.