Dynamic Pcu Values at Signalised Intersections in India for Mixed Traffic

Abstract

The traffic stream behaves differently in a mixed traffic condition as compared to that of a homogeneous condition. In a mixed traffic condition, as the traffic behaviour is always fluctuating based on the interaction caused by the surrounding elements, it is essential that the factors which affect the dynamic nature of the traffic characteristics should be considered for the proper design of the system. The paper highlights the methodology for developing the dynamic Passenger Car Unit (PCU) under various vehicular interactions for mixed traffic conditions prevalent in India. Experiments were carried out using the micro simulation model, TRAFFICSIM, which was developed for signalised intersections by the authors and reported elsewhere. The dynamic PCU values were obtained based on the analysis of the outputs of TRAFFICSIM, for varying approach width, traffic composition, stream speed and traffic volume. Modified area occupancy concept was used to develop Dynamic PCU values in a mixed traffic condition. In the modified area occupancy method, the area occupancy of the vehicle types for various traffic compositions is compared with area occupancy of the passenger cars in a car only traffic condition having the same stream speed. The study showed that the PCU values are highly sensitive to the given traffic conditions such as approach width, traffic composition, stream speed as well as flow ratio.

Estimation of Equivalency Units of Vehicles on Urban Roads for Heterogenous Traffic

“…VISSIM was originally developed in Germany, using a psycho-physical car-following model for the longitudinal movement of vehicles and a rule-based algorithm for lateral movement. Alex et al [30] obtained dynamic PCU values for varied approach width, stream speed, traffic composition, and traffic volume based on the analysis of the outputs of TRAFFICSIM.…”

Estimating Passenger Car Equivalent of Heavy Vehicles at Roundabout Entry Using Micro-Traffic Simulation

“…More common factors used to derive this value included studying the effects of traffic volume, delay, and gap acceptance. Other vehicle factors known to have an influence on PCE include its length, width, area, acceleration, deceleration, and average speed (Sheela and Kuncheria, 2015). The combinations of these factors lead to the assumption that every vehicle class has a different PCE value associated with it.…”

“…The combinations of these factors lead to the assumption that every vehicle class has a different PCE value associated with it. In addition to vehicle characteristics, other elements on the road have been shown to directly affect the PCE value of the vehicle including road and intersection geometry, volume of vehicles on the road, and the proportion of vehicle types on the road (Sheela and Kuncheria, 2015;Kang and Nakamura, 2016). These contributing factors lead to the development of a range of methods for estimating PCE of vehicles.…”

“…The studies on PCE values at regular intersections propose that the value should be expressed as a dynamic instead of a static number, contributed by several factors. Sheela and Kuncheria (2015) studied dynamic PCE values at a signalized intersection with mixed traffic conditions. It was found that width, speed, traffic composition, and volume yield had a direct influence on the PCE value, allowing one vehicle to have a varying factor depending on the circumstance.…”