Capacity Analysis of Unsignalized Intersection Under Mixed Traffic Conditions

Unsignalized intersection is implemented to regulate low volume of traffic flow. The gap-acceptance method is the common approach to assess the performance of the intersection. However, among the drawbacks of the gapacceptance method are the non-compliance to the right of way, and the heterogeneous traffic condition. Conflict method is developed to overcome these shortcomings. Surveillance equipment is used to obtain the required data, such as traffic volume and occupation time. The occupation time of vehicle is used to calculate the capacity of vehicular movements for each conflict group. The control delay and level of service of the vehicular streams are evaluated according to the procedures in HCM 2000. Result comparison is made between the conflict method and the HCM 2000. The relationship between the occupation time and critical gap is discovered. The results of the conflict method are found to be comparable with the HCM 2000 using field data.