Characteristics of vehicle headway during rainfall at night in Pontian, Johor

The headway pattern of a traffic stream has a significant impact on the accident possibility of the road section. The aim of this study is to determine the impact of different rainfall intensities have on the headway pattern in Pekan Nenas, Pontian, Johor. In this study, the automatic traffic count system (ATC) is utilised to obtain vehicle headway on the site. Rainfall data were obtained from the Department of Drainage and Irrigation, Pontian. The rainfall data was categorised into three rainfall intensity categories which are light rain, moderate rain and heavy rain. The traffic data and rainfall data then were then embedded to analyse the headway pattern of road user on the road section during rainfall at night. The results from the analysis showed that the headway pattern at night time followed the gamma distribution model. It was found that the mean vehicle headway increases as the rainfall intensity increases