Determination of Equivalent Passenger Car Unit for Motorcycles, Buses and Minibuses at Urban Signalized Intersections in Iran, Case Study: Isfahan and Yazd City

At present, the Equivalent Passenger Car Unit (PCU) values, proposed by other international guides, are used in the design and analysis of signalized intersections in Iran. It is likely that this would produce a negative impact of the accuracy of capacity analysis used for these intersections as the geometric design, behavioral attributes and vehicle characteristics are different here. Hence, it was decided to estimate the PCU values for buses, minibuses and motorcycles at Iranian signalized intersections using a multiple linear regression in this study. The required field data was collected from 9 intersections located at Isfahan and Yazd cities and the regression analysis was then performed on the data using SPSS software. Thereby, the PCU values for the motorcycles, minibuses and buses were obtained as 0.46, 1.45 and 2.53. Finally, an overall average PCU value of 2.13 was obtained for the heavy vehicles. The results could be used as the best estimate of PCU values for the similar Iranian signalized intersections.