Modeling Approach Capacity of Left most Shared Lane at Signalized Intersection with Channelized Left-turn Lane under Mixed Traffic Condition

抄録

Approach capacity of an intersection can be enhanced by adding a left turn lane with a specified length to the channelized intersection with flashing amber throughout entire cycle. But if there is no specified length of left-turn lane, through lane vehicles block the entrance of left-turn lane under heavy traffic conditions. Highway Capacity Manual does not address this issue. Frequent blockage of left turn channelization entrance increases the queue length, making it disadvantageous to left turn vehicles. Using conventional methods to calculate approach capacity without considering the impact of blockage would result in overestimation of the approach capacity. This research presents a probabilistic capacity model for signalized intersections with channelized left-turn lanes. The approach capacity model was developed based on the left-turn lane length and the proportion of left-turn traffic by considering the probability of blockage. Subsequently, the proposed capacity models were validated using VISSIM simulation.