Modelling the Performance of Signalized Intersections Near Railway Crossings

Railway related pre-emption time, which refers to the time needed to clear a vehicle from the pathway of a train, isa necessary input for appropriate pre-emption traffic signal settings. It is, however, usually left to the judgment of the signal engineer, using assumptions not always based on hard evidence. The research reported here analysed the safety and performance at railway crossings in the vicinity of signalized intersections with the aid of micro traffic simulation modelling. The developed model was calibrated by comparing the time that the last vehicle on the railway tracks to be cleared. A location in Brisbane, Australia, was chosen to apply the proposed methodology. The case study was used to evaluate three settings, which were implemented using fixed signal time; pre-emption with actuated signal; and actuated signal only. The signal logic was developed with the aid of an external signal controller to replicate pre-emption technology. The resultsfrom the simulation model show that the use of the pre-emption benefits safety and driving performance by changing signals dynamically in accordance withconditions related to traffic flow, train frequency and the proportion of heavy goods vehicles.