Individual and Synergetic Effects of Transit Service Improvement Strategies: Simulation and Validation

Assessment of transit service improvements such as bus lanes, allowing boarding through all doors, and headway-based holding control requires detailed simulation capabilities. However, because the usage of models advanced enough to simultaneously analyze physical and operational measures has been limited, their validity has hitherto remained low. This paper assesses the implementation of several bus service improvement measures in a simulation model. The paper analyzes the effect of isolated and combinations of measures, and validates the model using field experiment data. The model predicted travel time improvements accurately (1–2% difference), while overestimating some of the headway variability effects. The three tested measures exercised negative synergy effects, with their combined effect being smaller than the sum of their marginal contributions, except for headway-based holding, which exercised positive synergy effects with the two other measures.