TRAFFIC SIMULATION MODELING TO INVESTIGATE THE IMPACT OF ON-STREET MICROBUS-STOPS ON TRAFFIC FLOW

Abstract

Microbuses in Greater Cairo have almost become one of the largely public transit systems in the city’s lifeline. Operation of microbuses has been mostly unplanned and informal that causes interruptions in traffic flows due to the informal on-street stops that block some of the traffic lanes during the microbus dwell time and consequently reduce the traffic capacity of the roadway. The main objective of the study was to investigate the effect of Microbus-stops on traffic parameters and traffic operation by re-developing a macroscopic stochastic simulation model. Macroscopic traffic simulation models were created using the MATLAB programming language to simulate one microbus stop as well as two microbus stops with a defined separation distance. Model verification and validation were considered for the development of models that can be used to prediction reliable estimates for reduction in traffic speeds, change in traffic density and the average traffic delay due to the microbus stops. The models were utilized to study the effect of number of blocked lanes, microbus headway, microbus dwell time, separating distance between microbus stops, and different levels of volume to capacity ratios(v/c) on the traffic stream characteristics. Results of the one-stop models showed that the average speed upstream the microbus stop decreased and the average density gradually increased as the v/c ratio increased. The two-stop models were used to study the effect of the separating distance between microbus stops on traffic flow. Model results showed a significant increase in the average traffic delay due to the increase in v/c ratio. For case of one-lane blockage [BL=1], the average delay significantly increased as the v/c ratio increased. For the case of blocking two lanes [BL=2], traffic delay increased as the separating distance