Recent years, with rapid economic and social development, metropolises in China are confronting the contradictions between restrictions in road space resources and increasing demand of motorization.

• 近年来，随着社会经济的快速发展，我国许多大城市交通形势日益严峻，机动化交通需求的持续增长与道路空间资源短缺的矛盾不断加剧。