Abstract: In order to optimize the design of the left-turn waiting area in the mixed traffic environment, the compound relationship between left-turn motor vehicle delay and left-turn non-motor vehicle row width and swell number was determined by fitting the actual data. And the model of the number of the expansion conflicts between left-turn motor vehicle and non-motor vehicle in the waiting area and the traffic capacity calculation model of the left-turn waiting area under the influence of non-motor vehicles were proposed. Meanwhile, according to the severity of the conflict between left-turn motor vehicle and non-motor vehicle, the organization optimization methods of direct left turn and early release of non-motor vehicles were put forward respectively. Finally, taking the actual intersection as an example, the geometric settings of the waiting area and the organization of non-motorized vehicles were optimized, and the changes of the number of the expansion conflicts between left-turn motor vehicle and non-motor vehicle and the traffic capacity of the waiting area before and after the improvement were compared. The results show that when the conflict between motor vehicles and non-motor vehicles is serious, the intersection traffic efficiency is significantly improved; and the traffic capacity of the left-turn waiting area of the optimized intersections is basically unchanged, but the total number of conflicts decreases by 46.2% and 23.6%, respectively. The research shows that the proposed method of setting the left-turn waiting area under the influence of non-motorized vehicles can effectively reduce the safety hazards of mixed left-turn traffic flow at urban road intersections.

Key words: traffic engineering; left-turn waiting area; vehicle-non-motor vehicle conflict; signalized intersection; traffic capacity; delay

摘要： 为了对混合交通环境下左转待转区进行优化设计，通过拟合实际数据，确定左转机动车延误与左转非机动车排宽、膨胀数的复合关系，提出了待转区机非膨胀冲突次数模型及非机动车影响下的左转待转区通行能力计算模型；根据左转机非膨胀冲突的严重性，分别提出非机动车直接左转和提前放行的组织优化方式。最后以实际交叉口为例，从待转区几何设置以及非机动车组织方式进行优化，对比改进前后待转区机非冲突次数和通行能力的变化情况。结果表明：当左转机动车与非机动车冲突较为严重时，交叉口通行效益得到明显改善，并且优化后交叉口左转待转区通行能力基本不变，但总的冲突次数分别下降46.2%和23.6%，提出的非机动车影响下的左转待转区设置方法能够有效地降低城市道路交叉口混合左转车流的安全隐患。

关键词: 交通工程；左转待转区；机非冲突；信号交叉口；通行能力；延误