Abstract:

To reduce the negative effect on general traffic caused by bus signal priority (BSP), a methodology that considering saturation degree restriction and giving conditional priority to buses in premise of no traffic congestion occuring at the intersection was proposed, and a conditional active BSP strategy and a conditional passive BSP strategy at an isolated junction were established. The two strategies and non-priority strategy were simulated in VISSIM environment under various scenarios to get the corresponding control benefits. Using intersection average person delay as evaluation index, t test was applied to judge whether there were significant differences among the control benefits produced by three strategies and the optimal applicable circumstance of each strategy was determined. The results indicate that the active bus priority strategy is suitable to the circumstances when saturation degree is not larger than 0.85 and bus volume per lane is not larger than 30 veh/h. The passive bus priority strategy is suitable to the circumstances when saturation degree is not smaller than 0.875 and smaller than 0.925 and bus volume per lane is larger than 40 veh/h.

Key words: traffic and transportation systems engineering, signal control, conditional bus priority, active priority, passive priority, applicable circumstances