Study On Adaptive Traffic Volume Of Variable Lane At Signal-Controlled Intersections

In this paper,based on the relevant research on the left-turning variable lane,the signal-controlled intersection is selected as the research object to study the adaptability of the left-turning variable lane to the traffic volume.First,the definitions,applicable conditions,and respective advantages and disadvantages of left-turn widening lanes,left-turn waiting areas,left-turn variable lanes and reverse left-turn variable lanes are introduced,and the reverse left-turn variable lanes and other Three types of left-turn traffic organization methods are compared and analyzed,and their setting start conditions are clarified.Secondly,the setting parameters of the reverse left-turn variable lane are analyzed to set the intersection road and traffic conditions.Then,the minimum and maximum value of the adaptive traffic volume of the reverse left-turn variable lane is studied.The cumulative curve theory is used to analyze the relationship between the arrival and departure of vehicles at the entrance,and it is concluded that when the maximum number of vehicles leaving the cycle is equal to the number of vehicles arriving,the left-turn traffic organization mode reaches its applicable limit state.On this basis,the traffic wave theory is used to analyze the setting mode and setting conditions of the reverse left-turn variable lane,and the relationship between the lane length and the queue length,the relationship between the queue departure time and the effective green light time are established,and then Find the calculation formula of the threshold traffic volume and the minimum traffic volume.In the research process of adapting to the maximum traffic volume,on the basis of the equilibrium relationship between vehicle arrival and departure,the cumulative curve is used to represent the maximum number of vehicles that depart from the left-turn variable lane and the original left-turn lane in the signal period,and establish The calculation formula for adapting to the maximum value of traffic is given.Finally,verify the adaptability of the reverse left-turn variable lane to the traffic volume.Select an intersection that is consistent with the research settings to carry out traffic investigation,and substitute the obtained data into the calculation formula of adaptive traffic volume to obtain the theoretical value of the intersection’s adaptive traffic volume.Using VISSIM simulation software to establish the intersection model,using the average delay of vehicles,the length of the queue,and the number of passing vehicles as evaluation indicators,under different traffic conditions,the intersection is set to turn left and variable lanes before and after the change of vehicle operation,simulation It adapts to the range of traffic volume.Compared with the calculated theoretical value of the adaptive traffic volume,it is found that the error between the two is small,indicating that the research method of the adaptive traffic volume range is reasonable.