Congestion pricing for sustainable urban transportation systems considering carbon emissions and travel habits

Effective congestion pricing is essential for the sustainable development of urban transportation systems. To explore the impact of congestion pricing on travel behaviors and the urban environment, this paper investigates vehicular carbon emissions and travelers' car dependency under three different schemes of congestion pricing (CP), namely, charging by travel distance (CP1), charging by travel time (CP2), and charging by distance+time (CP3). The interaction between travel behavior adaptation and the corresponding CP scheme is considered in the bi-level model we constructed to determine the optimal rate for the best of regional traffic and carbon emissions. The results of the case study indicate that all schemes perform well in meaningful ways, while CP3 works the best in terms of carbon emission (-23.06 %) and car-mode share (-4.9 %). This suggests that CP3 is a more promising charging mode, as it tends to increase the complexity and psychological pressure for travelers looking for alternatives and inhibiting their car reliance and habitual paths. The findings are conducive to forming the habit of green mode use so as to facilitate carbon emission reduction and traffic jam alleviation, which provide references for policy-making and promote urban transportation systems to operate in an environmentally sustainable and socially responsible manner.