Abstract: Without considering the traffic phase of right-turning motor vehicles, according to the principle non-conflict of traffic flow in different directions within the same phase, 4 kinds of basic phases and phase sequence schemes of superposition release were obtained. Meanwhile, the applicable conditions of flow ratio of different phases and phase sequence schemes and other relevant influencing factors were analyzed. According to the characteristics of traffic flow in adjacent phases of superposition release, the methods for determining the flow ratio of the key lane groups of each phase, the loss time of the cycle phase and the signal period were given. On this basis, the phase effective green time algorithm model was established. The benefits of three kinds of signal control modes, namely single pass, symmetrical pass and superimposed pass, were evaluated by using the minimum signal period, the total flow ratio of key lane groups and other parameter indicators. Finally, combining with an example, the theoretical calculation and VISSIM software traffic simulation were used to furtherly verify the role of superimposed release signal control mode in shortening signal cycle and reducing traffic delay at intersections. The research results show that when the traffic flow ratio of the inlet lane of the intersection satisfies certain conditions, the superposition release signal control mode is adopted, the number of cycle phases increases but the cycle loss time remains unchanged. Moreover, by flexibly selecting the combination forms of the phases and phase sequence schemes, the road space-time resources can be fully utilized to effectively improve the traffic capacity of the intersection.

Key words: traffic engineering, superposition release, critical lane group, flow ratio, traffic delay, signal control mode

摘要： 在不考虑右转机动车通行相位的前提下，按照同一相位内不同方向交通流不冲突原则，得到了叠加放行4种基本相位相序方案，并分析了不同相位相序方案流量比适用条件及其它相关影响因素。根据叠加放行相邻相位交通流特点，给出了叠加放行各个相位关键车道组流量比、周期相位损失时间、信号周期确定方法，在此基础上建立了相位有效绿灯时间算法模型。采用最小信号周期、关键车道组总流量比等参数指标，对单口放行、对称放行、叠加放行3种信号控制方式效益进行了评价。最后结合实例，运用理论计算及VISSIM软件交通仿真两种方法，进一步验证了叠加放行信号控制方式在缩短信号周期、减少交叉口交通延误等方面发挥出的作用。研究结果表明：当交叉口进口车道流量比符合一定条件时，采用叠加放行信号控制方式，周期相位数增加但周期损失时间不变，而且通过灵活选取相位相序方案组合形式，可以充分利用道路时空资源，有效提高交叉口的通行能力。

关键词: 交通工程, 叠加放行, 关键车道组, 流量比, 交通延误, 信号控制方式