Methodology for estimating capacity and vehicle delays at unsignalized multimodal intersections

An uncontrolled intersection is one where neither traffic signs nor lights, are used to guide the traffic through the intersection, but instead the drivers decide on the right of way based on some standard priority rules. This paper establishes a methodology to systematically evaluate the expected average delays at multi-modal uncontrolled intersections. The methodology considers the demand values of different traffic streams, along with the priority and direction of each stream to determine the capacity available for each. Using this capacity and the formula for delay adapted from the highway capacity manual, the average delay for each vehicle stream can be determined. The methodology is tested using data collected at five locations in Zurich, Switzerland. The results show that the methodology can predict the delay of different vehicle streams to within 4 s/veh, and also can identify the streams for which large delays would be expected.