关键词: 交通工程, 信号配时优化, 0-1混合整数线性规划, 交叉口, 行人保护策略

Abstract:

To promote pedestrians' safety at intersections, this paper establishes a signal timing optimization model based on the NEMA dual-ring standard by incorporating three pedestrian protection strategies, i.e., exclusive pedestrian phase (EPP), concurrent yet protected phase (CYPP), and leading pedestrian interval (LPI). The model aims at minimizing the cycle length and the conflicts between right-turn vehicles and pedestrians. By supposing that the traffic users obey the signal rule, the model can eliminate most of the conflicts, leaving only the conflicts between far- side pedestrians and right-turn vehicles under LPI control. The model belongs to Binary-Mix- Integer- Linear- Program (BMILP) and can be solved by the branch-and-bound method. Two intersections in the city of Nanjing are selected for a case study. The results show that when the intersection size is small and the traffic volume is low, the EPP is more likely to be obtained; the CYPP or LPI is otherwise. When the shared through-right lane is set in the intersection arm or the right-turn phase is not easy to meet the maximum volume-to-capacity ratio, LPI is more likely to be obtained.

Key words: traffic engineering, signal timing optimization, binary mix integer linear program, intersection, pedestrian protection strategy