Simulation and Evaluation of the Left-turn Waiting Zone at Signalized Intersection

In order to simulate traffic operations of the left-turn waiting zone(LWZ) at signalized intersection to quantitatively evaluate the operational performances after the implementation of the LWZ,following the introduction of the concept of the LWZ,the modeling method of the LWZ was established,and the simulation evaluation volumes indexes were selected.Based on the data investigation,the simulation model was applied to a typical signalized intersection with left-turn lanes by microsimulation software Vissim to evaluate the efficiency of the traffic operation.It is found that compared with the layout of lacking LWZ,the left-turn traffic capacity at signalized intersection increased by 5.9,4.3 and 6.7 percent in three different periods of traffic levels respectively after using the LWZ.The results show that optimizing the layout of the intersection by using the LWZ can improve the operation efficiency without affecting the traffic safety.