Abstract: In order to analyze the causation and evolution process of early on-set breakdown at bottlenecks deeply, the lane changing motivation model was established based on the whole vehicles' trajectory data at Hongxu Road on-ramp bottleneck in Shanghai China. The results show that prediction accuracy of the lane change motivation model is more than 73%. On this basis, the on-ramp microscopic traffic flow simulation proto type system ORBSIM was established with calibrated critical gap and IDM model in the C++ platform. The simulation results show that the ORBSIM can recur traffic flow characteristics and early on-set breakdown phenomenon. For further engineering using, this model was developed and integrated in micro simulation system TESS NG, and the results show that the model can simulate the merging behavior more effective at urban expressway on-ramp in different traffic situations in China.

Key words: urban expressway, bottleneck, merging behavior, logit motivation model, micro simulation system TESS NG