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Microscopic traffic simulation is a powerful tool for studying complex traffic systems when analytical or empirical approaches cannot define response patterns adequately and accurately. The application of simulation techniques for evaluating the characteristics of controlled intersections is effective due to their quick and reliable outcomes. This paper presents a methodology for model development and a unique calibration process for mixed traffic streams using the widely used simulation software Vissim. An isolated signalised intersection was selected for the model development. Most of the calibration methodologies described in previous literature were based on informal practices based on a homogeneous traffic stream. This study frames a novel calibration process suitable for mixed traffic streams. The validity of the proposed methodology was evaluated using field data from another signalised intersection by means of a feasibility comparison of field data and simulation outputs. The calibrated parameters produced suitable simulation outputs, with the measure of effectiveness matching the result obtained from actual field conditions. In contrast, simulations with default or best-guess parameters resulted in significant discrepancies between the observed and simulated outputs.

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The estimation of the saturation flow is the utmost component for performance evaluation of a signalized intersection. The flow rate estimation procedure includes the analysis of the vehicles headway, vehicles discharge rate, passenger car unit, effective green time and cycle length of the signalling system. This study attempts to exhaustively review the existing literature and its suitability along with the multiple factors affecting the performance of signalized intersection. Different methodological approaches and soft computing techniques used worldwide by the researchers both in developed and developing countries are emphasized. This study also highlights the several influencing factors that have a significant impact on saturation flow value and several methodological approaches to determine the flow value through normalizing the influencing factors, which lead to a better way for planning and designing of a signalized intersection.