中文摘要：

了解信号交叉口下游车辆的车头时距分布特征是进行城市道路控制、通行能力计算、交通安全分析等的基础．利用NC200、MC5600对信号交叉口下游不同断面不同车道的车头时距进行调查．采用X2检验法对信号交叉口下游车辆的车头时距分布进行拟合，得到高峰时段和平峰时段的不同断面、不同车道车头时距分布．研究结果表明：随着高峰时段向平峰时段过渡，以及车辆由交叉口向下游移动，车道的车头时距在移位负指数分布和M3分布之间进行过渡．

英文摘要：

The time headway distribution is a vital foundation for the work of traffic control, capacity calculation, traffic safety analysis, etc. In this paper, the traffic investigation equipment NC200 and MC5600 are utilized to obtain the time headway data of different road section and different lanes on the downstream section of signalized intersection. The method of chi square test is adopted to analyze the time headway distribution, and obtains the characters of different road section and different lanes in the peak period and the normal period. The results indicate that with the time elapsing from the peak to normal period and the vehicles moving from the intersection to downstream section, the time headway distribution on the lanes are transformed between the shifted negative exponential distribution and M3 distribution.