Comparison of User-equilibrium and System-optimal Route Flow Solutions under Increasing Traffic Congestion

摘要

Using an advanced traffic assignment tool (TAPAS), unique route flows can be obtainedfor precisely converged solutions of traffic assignment problems. Comparisons of userequilibriumand system-optimum solutions for three trip matrices are presented for two roadnetworks. Then, flow patterns on two small-scale networks are analyzed. Results show thatincreasing traffic congestion has a substantial impact on the difference in flows between the userequilibrium and system optimum when link cost functions are super-linear; in contrast, for linearlink cost functions, such differences may be independent of travel demand.