Extraction of Catastrophe Boundary and Evolution of Expressway Traffic Flow State

As the main road type in an urban traffic system, increasingly severe congestion of expressway restricts social and economic development. It is essential to explore evolution law dissipation ensure efficient operation expressway. In order accurately grasp flow state, this paper selects weaving section, which a frequency-changing area, study change process, law, determine state discrimination standard. The simulation analysis was carried out using platform, Vissim software. results showed apparent catastrophe phenomenon mutual transformation between free flow. spectral clustering algorithm used extract boundary mutation, combined with cusp theory, analyze at different times positions, thus completely displaying characteristics state. research provide theoretical basis for formulating control measures strategies dissipation.