中文摘要：

在信号交叉口设置预信号可以实现公交车辆在社会车辆之前排队，当主信号绿灯启亮后公交车辆优先通过交叉口。然而，设置预信号在减少公交车辆延误的同时，会增加社会车辆延误，因此预信号设置时需要满足一定条件才能取得理想效果。本文从车道数量、车道利用率及人总延误三方面研究设置预信号需要满足的条件。首先介绍设置预信号交叉口的布局型式，然后介绍进口道设置预信号前后的延误计算方法，最后分析预信号设置条件。研究表明：在进口道有两条直行车道处设置预信号，当车道利用率不均衡系数在0．5-1．7范围内、公交比例大于0．3、车道饱和度大于0．40时设置预信号能显著减少交叉口延误并且对社会车辆影响较小。

英文摘要：

Pre-signal intersections make it possible for buses to queue before social vehicles and the buses get through intersections prior to social vehicles. Setting pre-signals can reduce the delay of buses, whereas it would increase the delay of social vehicles at the same time. Thus, in order to achieve the ideal effect some conditions have to be met when setting pre-signals. This paper studied the conditions of the lane numbers, lane utilization rate and total delay which make setting pre-signal reasonable. First, the layout approaches of pre-signal were introduced; Second, the total delays with and without pre-signal were researched respectively; Finally, the conditions setting pre-signals were analyzed.Research showed that setting pre-signal on a two-straight-lane intersection reduced the total delay and had little impact on social vehicles when lane utilization imbalance factor ranged between 0.5 and 1.7, bus ratio greater than 0.3 and lane saturation greater than 0.40.