Abstract: With the accelerating pace of urbanisation, traffic congestion, environmental pollution and safety concerns have become increasingly prominent. As key nodes within the road network, the traffic organisation and signal control at intersections play a crucial role in enhancing traffic flow efficiency and alleviating congestion. Dynamic signal timing optimisation for traffic-controlled intersections is achieved by solving for initial values based on the Webster method, combined with a genetic algorithm (GA). Taking the intersection of Changcheng Road and Xingyang Road in Qingdao as the research object, the data collection is carried out by the method of on-site terrain survey combined with video recording observation. The PTV-VISSIM (2025) software is used to establish the models of the intersection before and after optimization and the relevant service evaluation. The research results show that after the timing optimization, the overall delay of the intersection is reduced by 24.03%, and the service level is improved from D to C, significantly improving the operation efficiency of the intersection, thereby verifying the feasibility of the optimization scheme.

Key words: Webster method; genetic algorithm; signal timing; intersection simulation optimization

摘要： 随着城市化进程的不断加快，交通拥堵、环境污染、安全问题日益突出。作为路网交 通枢纽，交叉口的交通组织与信号控制对提升通行效率、缓解交通压力具有关键作用。基于 Webster 法作为初始值求解，结合遗传算法（GA）对信控交叉口进行动态信号配时优化。以 青岛市长城路与兴阳路交叉口为研究对象，采用实地地形勘察结合视频录像观测的方法进行 数据采集，运用 PTV-VISSIM（2025）软件建立交叉口优化前后模型以及相关服务评价体系。 研究结果表明，经过配时优化后交叉口的总体延误减少 24.03%，服务水平由 D 提升到 C，显 著提升了交叉口的运行效率，从而验证优化方案的可行性。

关键词: Webster 法；遗传算法；信号配时；交叉口仿真优化