The aim of this study was to explore the viability of microsimulation in estimating critical gaps at unsignalised intersections. Critical gaps are generally estimated by extracting gap acceptance data from traffic videos. Extracting such data is a strenuous task, especially under mixed traffic conditions. In this study, gap acceptance data were generated from simulation models developed in the Vissim software package. Critical gaps of three unsignalised intersections were estimated using field data and simulated data of the intersections. Critical gaps were estimated by the logit method and the clearing time method. The critical gaps estimated using simulated data were reasonably close to those obtained using field data for both methods. The results also showed that the logit method was more robust than the clearing time method in estimating critical gaps under mixed traffic conditions. Moreover, the time needed for generating simulated data was only 3.6% of that required for obtaining field data. The method proposed in this study will help traffic engineers and practitioners in critical gap estimation by saving a considerable amount of time and effort.

中文翻译：

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使用微观模拟在三足无信号交叉口处实现关键间隙

本研究的目的是探索微观模拟在估计无信号交叉口关键间隙方面的可行性。通常通过从交通视频中提取间隙接受数据来估计关键间隙。提取此类数据是一项艰巨的任务，尤其是在混合交通条件下。在本研究中，间隙接受数据是通过 Vissim 软件包开发的仿真模型生成的。使用现场数据和交叉口的模拟数据估算了三个无信号交叉口的关键间隙。通过logit方法和清除时间方法估计关键间隙。使用模拟数据估计的关键差距相当接近使用这两种方法的现场数据获得的关键差距。结果还表明，在估计混合交通条件下的关键间隙时，logit 方法比通车时间方法更稳健。而且，生成模拟数据所需的时间仅为获取现场数据所需时间的3.6%。本研究中提出的方法将帮助交通工程师和从业人员节省大量时间和精力来估计关键间隙。