为完善道路交通信号灯设置与安装规范，以不同车流的优先通行规则为基础，提出了T 型交叉口各股车流之间的冲突矩阵，并基于可接受间隙理论和排队论建立了车流通行能力及无信号交叉口车均延误模型．在此基础上，以交通流的运行效率最优为控制目标，以车均延误为判别指标，描述了信号设置前后交叉口车均延误差值与车流流量的变化关系; 取延误较小者为最优控制方式，得到特定条件下需设置信号的临界流量条件．

In order to improve the allocation and installation specifications of traffic signal lights for road,the conflict matrix of various vehicle flows at T-intersections is proposed based on right-of-way rules,and then two models of the traffic capacity and the average vehicle delay at one unsignalized intersection are obtained according to the gap acceptance and queuing theories. Then,from the viewpoint of traffic efficiency,the average vehicle delay is taken as the discriminant index to describe the relationship between the difference of the average vehicle delay before and after the signal setting and the movement volume. Finally,the critical traffic volumes for the signal setting under specific conditions are achieved via the optimal control pattern with lower delay.