Calibrating and Validating VISSIM Microscopic Simulation Software for the Context of Sri Lanka

At present, majority of traffic management initiatives are mostly based on trial and error procedures, where no proper traffic theory or simulations are involved. When considering the context of Sri Lanka, the use of traffic simulation software has been the newest addition for the traffic engineering field. However, the outputs obtained from VISSIM traffic simulation software can become unrealistic, if no proper calibration is conducted for the local context. Therefore, the aim of the research is to develop a calibration procedure and identify representative values for parameters required for VISSIM micro simulation software to suit the local Condition. Based on the findings of the literature review, 9 key parameters were identified for calibration purposes of VISSIM, which are further reduced to 5 key parameters based on the sensitivity using statistical tools. These 5 parameters were further simulated in order to identify optimum input values, resulting in minimum percentage error for the difference between observed and simulated queue lengths. The calibrated parameters were successfully validated using 23 signalized intersections in Colombo and Gampaha Districts and these parameter values can be used in future traffic and transportation micro simulation studies.