平行流交叉口左转非机动车钩形转弯优化设计

To boost the operational efficiency of parallel flow intersections and further eliminate the conflict between left-turn non-motor and straight-through motor vehicles, a control strategy for non-motor vehicle crossing was proposed and then integrated with motor vehicle crossing and pedestrian crossing into a unified optimization model. Considering the constraints such as signal phase sequence, green light timing, cycle length, capacity of the waiting area for leftk-turn non-motor vehicles, clearance time of non-motor vehicles, and lane balance, the linear programming optimization model was constructed so as to maximize traffic capacity. Results show that two-step street crossing and optimization design could both solve the crossing problem of left-turn non-motor vehicles, which are effective alternative design schemes for non-motor vehicle crossing at parallel flow intersections. Compared with conventional design, the two-step street crossing reduced the motor vehicle delay by 35. 02% and 55. 52% respectively in high and low traffic flow scenarios, while the optimization design reduced it by 42.71% and 65.60% respectively. The two-step street crossing caused a significant increase in left-turn non-motor vehicle delays, so it is not applicable when the flow of left-turn non-motor vehicles is high. The maximum motor vehicle traffic volume of conventional design was most affected by the flow of left-turn non-motor and straight-through motor vehicles. It indicates that avoiding the conflicts between left-turn non-motor vehicles and straight-through vehicles plays a significant role in improving the traffic capacity at intersections, which can be helpful for promoting the development of green travel.